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TCVN 5593:2012 Building engineering - Permissible tolerances in geometry
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TCVN 5593:2012
TCVN 5593:2012
TCVN 5593:2012
TCVN 5593:2012 Building engineering – Permissible tolerances in geometry
Foreword
TCVN 5593:2012 replaces TCVN 5593:1991.
TCVN 5593:2012 was converted from TCVN 5593:1991 in accordance with the provisions of clause 1 Article 69 of the Law on Standards and Technical Regulations and point a) clause 1 Article 6 of the Government’s Decree 127/2007/ND-CP dated August 1, 2007 detailing the implementation of some articles of the Law on Standards and Technical Regulations.
TCVN 5593:2012 was compiled by the Institute of Architecture, Urban and Rural Planning – Ministry of Construction, proposed by the Ministry of Construction, appraised by the Directorate for Standards, Metrology and Quality, and promulgated by the Ministry of Science and Technology.
1. Scope of application
1.1. This standard specifies permissible geometric deviations in construction and installation works, applicable to residential buildings and public works.
For works in other specialized fields or with high quality requirements, the specific regulations of those specialized fields must be followed.
1.2. This standard is one of the bases for evaluating the quality of completed construction and installation works.
1.3. The works can only be accepted when the actual construction deviations do not exceed the permissible deviations specified in this standard.
2. Earthworks
2.1. Site leveling
Only carry out site leveling when there are design instructions on elevations and drainage measures.
The permissible deviation of the elevation at individual points when leveling the site (provided that the drainage direction is maintained) compared to the design elevation is specified in Table 1.
Table 1 – Permissible deviation of elevation at individual points when leveling the site
| Deviation name | Permissible deviation % |
| 1. Slope of the leveled surface, not more than | 1 |
| 2. Slope of drainage ditches, not more than | 1 |
| 3. Thickness of the surface soil layer, not more than 10 | 10 |
2.2. Surface drainage works
Permissible deviations for surface drainage works compared to the design are specified in Table 2.
Table 2 – Permissible deviations for surface drainage works compared to the design
| Deviation name | Permissible deviation % |
| 1. Longitudinal slope along drainage ditches from excavations, not more than | 2 |
| 2. Longitudinal slope along drainage ditches in marshes, river banks, not more than | 1 |
| 3. Longitudinal slope along open ditches in excavations leading to water inlet | from 2 to 5 |
2.3. Excavation and backfilling works
2.3.1. When excavating foundation pits and trenches, the excavation must not be deeper than the elevation of the structure placement and violate the natural structure of the foundation soil. Deviations in the thickness left at the bottom of the excavation are specified in Table 3.
Table 3 – Permissible deviations of the thickness left at the bottom of the excavation
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Permissible thickness left at the bottom of the pit, not more than | |
| – When excavating by machines | 100 |
| – When excavating manually | 100 |
| 2. Deviation of the bottom elevation of precast foundation pits compared to the design | ± 50 |
2.3.2. When constructing some earth structures, the deviations are specified in Table 4.
Table 4 – Permissible deviations when constructing some earth structures
| Deviation name | Permissible deviation |
| 1. Axis deviation of the earth foundation on the plan (deviation according to the slope) | Not allowed |
| 2. Narrowing of the ditch bottom | Not allowed |
| 3. Deviation of the slope of ditches and trenches, % | ± 1 |
| 4. Deviation of the elevation of the earth foundation surface (except for building foundations and structures of trenches for laying non-pressure pipes), mm | ± 50 |
| 5. Deviation of the width of the earth embankment berm (provided that the design slope of the slope is ensured with an accuracy of up to 10%), mm | ± 100 |
3. Monolithic concrete and reinforced concrete works
3.1. Formwork and scaffolding works
3.1.1. When installing floor slabs into the scaffolding, one of the four supports of the slab is allowed to be no more than 2 mm away from the support beam.
3.1.2. Deviations when erecting scaffolding and reinforcement components are specified in Table 5.
Table 5 – Permissible deviations when erecting scaffolding and reinforcement components
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the distance between the formwork support columns, bending members and the distance between the support columns, braces attached to the support columns compared to the design distance: | |
| – Per 1 m length | ± 25 |
| – Entire span | ± 75 |
| 2. Deviation of the formwork plane and their intersecting lines from the vertical or design inclination: | |
| – Per 1 m height | 5 |
| – Over the entire height of the structure | |
| + Foundation | 20 |
| + Walls and columns supporting monolithic slabs with a height less than 5 m | 10 |
| + Walls and columns supporting monolithic slabs with a height greater than 5 m | 15 |
| + Frame columns connected by beams | 10 |
| + Arch beams | 5 |
| 3. Deviation of the formwork axes from the design position | |
| + Foundation | 15 |
| + Walls and columns | 8 |
| + Beams and arches | 10 |
| + Foundation under steel structures | 1.1 √La) |
| 4. Deviation of the distance between the inner faces of the wall formwork and the deviation of the internal dimensions of the cross-section of the box-shaped formwork compared to the design dimensions. | 3 |
| 5. Local roughness of the formwork when checked with a 2 m ruler. | 3 |
| NOTE: a) L is the span length (structure step in meters) | |
3.1.3. Permissible deviations when erecting sliding formwork are specified in Table 6.
Table 6 – Permissible deviations when erecting sliding formwork
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the formwork axis compared to the design | 10 |
| 2. Maximum difference of the elevation marks of the upper shell plane or the working floor at a distance of: | |
| – Under 3 m | 10 |
| – From 3 m to under 6 m | 15 |
| – From 6 m and above | 20 |
| 3. Deviation of the position of the axes of the jacking rods and the axes of the jacks from the vertical | 1/2 000 |
| 4. Maximum difference of the first elevation marks of the clamping parts of the same type jack frames | 10 |
| 5. Deviation of the taper of the sliding formwork (taper in the opposite direction is not allowed at each end) | + 4; – 2 |
| 6. Deviation of the distance between the formwork walls (according to the wall thickness) | ± 5 |
| 7. Offset of the jack axis compared to the wall axis | 2 |
| 8. Deviation in the distribution of the position of the jack frames along the wall | ± 10 |
3.2. Reinforcement works
3.2.1. Reinforcement in reinforced concrete structures must be fabricated and installed in full accordance with the design. If not specified in the design, the permissible deviations must comply with this standard.
3.2.2. The thickness of the reinforcement protective layer must follow general regulations. Permissible deviations of the protective layer are specified in Table 7.
Table 7 – Permissible deviations of the reinforcement protective layer
Dimensions in millimeters
| Deviation name | Permissible deviation when the protective layer thickness is | ||
| 10 | 15 | 20 and greater | |
| – Under 400 | 3 | ± 3 | ± 5 |
| From 400 and above | 3 | + 5; – 3 | + 10; – 5 |
3.2.3. Deviations of reinforcement after bending are specified in Table 8.
Table 8 – Permissible deviations of reinforcement after bending
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation in length dimensions of load-bearing reinforcement: | |
| a) Each meter of length | ± 5 |
| b) Total length | ± 20 |
| 2. Deviation in the position of the bending point | ± 20 |
| 3. Deviation in the length of reinforcement in large concrete structures: | |
| – When the length is less than or equal to 10 m | + d |
| – When the length is greater than 10 m | + (d + 0.2 a) |
| 4. Deviation in the bending angle of reinforcement | 3° |
| 5. Deviation in the dimensions of bending hooks | + a |
| NOTE: d – Reinforcement diameter (mm) a – Protective layer thickness (mm) | |
3.2.4. Deviations in reinforcement fabrication are specified in Table 9.
Table 9 – Permissible deviations in reinforcement fabrication
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation in the overall dimensions of welded flat frames and welded meshes as well as along the length of separately fabricated bars: | |
| a) Reinforcing bar diameter not exceeding 16 mm | |
| – Along the product length | ± 10 |
| – Along the width or height of the product | ± 5 |
| – When the product dimensions in width or height do not exceed 1 m | ± 3 |
| b) Reinforcing bar diameter from 10 mm to less than 40 mm | |
| – Along the product length | ± 10 |
| – Along the width or height of the product | ± 10 |
| – When the product dimensions in width or height do not exceed 1 m | ± 5 |
| c) Reinforcing bar diameter from 40 mm and above | |
| – Along the product lengt | ± 50 |
| – Along the width or height of the product | ± 20 |
| 2. Deviation in the spacing between transverse bars (connecting bars) of welded frames | ± 10 |
| 3. Deviation in the spacing between individual load-bearing bars of flat or spatial frames with a bar diameter of: | |
| – Under 40 mm | ± 0.5 d |
| – From 100 mm and above | ± 1 d |
| 4. Planar deviation of welded meshes or flat welded frames when the bar diameter is: | |
| a) Under 12 mm | 10 |
| b) From 12 mm to 24 mm | 15 |
| c) From 25 mm to 49 mm | 20 |
| d) From 50 mm and above | 5 |
| 5. Deviation in the position of the bending point of the bar | 2 d |
| 6. Deviation of the centers of joints of reinforcement frames (along the beam axis) | 15 |
| 7. Deviation in the position of the construction deflection of load-bearing reinforcement frames compared to the design | 5% |
3.2.5. Deviations for reinforcement welds and permissible defects of those joints are specified in Table 10.
Table 10 – Permissible deviations for reinforcement welds and permissible defects
| Deviation name | Permissible deviation |
| 1. Offset of the centerline of 2 round splice bars relative to the axis of the spliced steel bar (when there are 2 splice bars and the weld is on 1 side) | 0.1d to the other side of the weld |
| 2. Deviation in the length of various backing bars and splice bars | ± 0.5 d |
| 3. Offset of the splice bar relative to the weld axis in the longitudinal direction (except for welds with staggered splice bars) | 0,5 d |
| 4. Offset of the splice bar for welds with formwork | 0.1 d |
| 5. Misalignment of the bar axes at the weld | 3° |
| 6. Offset of the bar centers at spliced welds | |
| a) When welding with formwor | 0.05 d |
| b) When welding with round splice bars | 0.1 d |
| c) When butt welding | 0.,1 d |
| 7. Deviation in the length of side welds | ± 0.5 d |
| 8. Deviation in the width of side welds | 0.15 d |
| 9. Lack of fusion of the weld toe with the steel angle when using the multilayer welding method, bar diameter greater than 40mm. Cracking in the welds, large and multiple porosity defects, bar fractures | not allowed |
| 10. Width of lack of fusion with the steel angle when welding by the multilayer method or when welding bars with a diameter less than 40 mm | 0.1 d |
| 11. Depth of arc strikes on plates and shapes when welding with round bars or angles | not more than |
| 12. Number of pores and slag inclusions in the weld: | |
| a) On the weld surface in a length of 2d | 3 places |
| b) In the weld cross-section: | |
| – When d is less than or equal to 16 mm | 2 places |
| – When d is greater than 16 mm | 3 places |
| 13. Average diameter of pores entrapped in the weld: | |
| a) On the weld surface | 1.5 |
| b) In the weld cross-section: | |
| – When d is less than or equal to 16 mm | 1 |
| – When d is greater than 16 mm | 1.5 |
Dimensions in millimeters
3.2.6. Deviations when installing reinforcement are specified in Table 11.
Table 11 – Permissible deviations when installing reinforcement
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation in the spacing between individually placed load-bearing bars: | |
| – For large-scale structures | ± 30 |
| – For columns, beams, arches | ± 10 |
| – For slabs, walls and foundations under frame structures | ± 20 |
| 2. Deviation in the spacing between rows of reinforcement when arranging multiple rows in height: | |
| a) In structures with a thickness greater than 1 m and in foundations under structures and technical equipment | ± 20 |
| b) In frame beams and slabs with a thickness greater than 100 mm | ± 5 |
| c) In slabs with a thickness up to 100 mm and a protective layer thickness of 10 mm | ± 3 |
| 3. Deviation in the spacing between the stirrups of frames and reinforced concrete beams. | ± 10 |
| 4. Local deviation in the thickness of the protective layer | |
| a) In large-scale structures (thickness greater than 1 m) | ± 20 |
| b) In foundations under structures and technical equipment | ± 10 |
| c) In columns, beams and arches | ± 5 |
| d) In walls and slabs with a thickness greater than 100 mm | ± 5 |
| e) In walls and slabs up to 100 mm thick with a protective layer thickness of 10 mm | ± 3 |
| Deviation in the spacings between hole components in 1 row: | |
| a) For walls | ± 25 |
| b) For large-scale structures | ± 40 |
| 6.Deviation in the position of stirrups relative to the vertical or horizontal (excluding cases when the stirrups are placed at an angle according to the design) | ± 10 |
| 7. Deviation in the center position of bars placed at the ends of field-spliced welded frames with other frames when: | |
| a) The bar diameter is under 40 mm | ± 5 |
| From 40 mm and above | ± 10 |
| Deviation in the position of bar welds along the length of the member: | |
| a) In frames and wall structures, foundations | ± 25 |
| b) In large-scale structures | ± 50 |
| 9. Deviation of the position of reinforcement components of large-scale structures (welded block frames) compared to the design: | |
| a) In plan | ± 50 |
| b) In height | ± 30 |
| NOTE: The permissible deviations when placing reinforcement with bars having a diameter greater than 90 mm, as well as when placing welded frames made of shaped steel, pipe steel are specified according to the design. | |
3.2.7. Permissible deviations when preparing the installation and tensioning of prestressing reinforcement are specified in Table 12.
Table 12 – Permissible deviations when preparing the installation and tensioning of prestressing reinforcement
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Relative displacement of the wedge ends at the end of the steel tendon, mm | 0.00005 of the tendon length |
| 2. Deviation of the distance between the inner plane of the cup anchor and the wedge anchor, mm | + 0.001 of the tendon length but not more than + 50 mm and not less than -10 mm |
| 3. Deviation of the control length of steel bars, cables and tendons when tensioning the entire group, mm | 0.03 of the elastic elongation of the reinforcement during tensioning |
| 4. Deviation of the spacing between steel bars, tendons and cables when the clear spacing is, mm: | |
| – Less than or equal to 60 mm | 5 |
| – Greater than 60 mm | 10 |
| 5. Deviation of the anchor position while tensioning tendons and cables on the bed, mm: | |
| a) Tendons and cables adjacent to the block edge towards: | |
| – The block edge | 40 |
| – The block center | 60 |
| b) The remaining anchors in any direction, mm | 200 mm when the actual distance between the anchors along the block length is not less than 10 mm |
| 6. Displacement of the bearing surface for the position of placing jacks and anchors, mm | Not greater than 1/100 |
| 7. Deviation of the length of the steel bar between the bearing surfaces of the supports or between the bearing surfaces of the loop anchors when tensioning by the electric heat method, mm | 0.0001 of the bar length |
| 8. Deviation of the value of the tensile force of the reinforcement by jacks (compared to the control stress at the time close to the end), in each bar, wire, tendon and cable,%: | |
| – Tensioning in sequence | 5 |
| – Tensioning the entire group | 10 |
| – Total tensioning for all bars, wires, tendons and cables in one group | 5 |
| 9. Deviation in the value of elongation in bars, wires, tendons and cables, % | 15 |
| 10. For all bars, wires, tendons and cables in one group, % | 10 |
| 11. Deviation in the value of the tensioning force when tensioning by the electric heat method, %: | |
| – In each bar | 10 |
| – For all bars | from +10 to -9 |
| NOTE: It is allowed to leave in prestressed structures 20% of the number of tendons out of the total number of tendons in the structure, having broken or not fully tensioned wires (but the number of broken or not fully tensioned wires must not be greater than 50% of the total number of wires in that tendon). | |
3.3. Concrete works
Permissible deviations when constructing monolithic concrete and reinforced concrete structures are specified in Table 13.
Table 13 – Permissible deviations when constructing monolithic concrete and reinforced concrete structures
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of planes and their intersecting lines from the vertical or design inclination, calculated for the entire height of the structure: | |
| a) For foundations | ± 20 |
| b) For walls cast in fixed formwork | ± 15 |
| c) For frame building columns connected by crane beams or tie beams and columns supporting monolithically cast slabs. | ± 10 |
| 2. Deviation of the concrete surface from the horizontal plane: | |
| – Calculated for 1 m of the plane in any direction | 5 |
| – For the entire structure | 20 |
| 3. Local deviation of the top concrete plane from the design when checked with a 2 m long ruler pressed tightly against the concrete surface | ± 5 |
| 4. Deviation in length or span of structural members | ± 20 |
| 5. Deviation in the cross-sectional dimensions of structural members | + 6; – 3 |
| 6. Deviation in the dimensions of trenches, tunnels for equipment: | |
| a) Position | ± 10 |
| b) Spacing between centers | ± 15 |
| c) Kích thước theo chiều ngang | ± 10 |
| 7. Deviation in the installation of anchor bolts: | |
| a) On the plan within the column | 5 |
| b) On the plan outside the column | 10 |
| c) In heigh | + 20 |
| 8. Deviation in the elevation of the surface and embedded parts used as supports for steel columns or precast reinforced concrete columns and other components | – 5 |
| 9. Difference in elevation between 2 adjacent planes at their joint | 3 |
4. Precast concrete and reinforced concrete works
4.1. General requirements
For additional parts and spacers, the following defects and errors are not allowed: cracks, delamination, jagged edges or beveled cuts at the ends with an inclination exceeding 15° from the square, indentations deeper than 0.1 times the thickness of the part or the wall diameter.
4.2. Production and assembly of foundations
4.2.1. Dimensional deviations of precast foundations are specified in Table 14.
Table 14 – Dimensional deviations of precast foundations
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Length, width | ± 20 |
| 2. Thickness or elevation of the bearing surface | ± 10 |
4.2.2. Permissible deviations when assembling precast foundation blocks of residential buildings and public works are specified in Table 15.
Table 15 – Permissible deviations when assembling precast foundation blocks of residential buildings and public works
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. For the axis of the foundation pad | ± 15 |
| 2. For the axis of the foundation socket | ± 15 |
| 3.Elevation of the bearing surfaces on the foundation compared to the design | ± 10 |
4.3. Production and installation of columns
4.3.1. Permissible deviations from the design when producing columns are specified in Table 16.
Table 16 – Permissible deviations from the design when producing columns
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. When the column height is 9 m and below | |
| – Column height | ± 10 |
| – Dimensions of the sides of the column cross-section | ± 8 |
| 2. When the column height is above 9 m | |
| – Column heigh | ± 10 |
| – Dimensions of the sides of the column cross-section | ± 8 |
4.3.2. Permissible deviations when assembling columns of residential buildings and public works are specified in Table 17.
Table 17 – Permissible deviations when assembling columns of residential buildings and public works
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the column axis at the column base section from the reference axis. | ± 5 |
| 2. Deviation of the column axis from the vertical at the top section of the column: | |
| – When the column height (H) is 4.5 m and below | ± 5 |
| – When the column height (H) is greater than 4.5 m | 0.001 H but not more than 35 |
| 3. Deviation of the top elevation of the column or of the bearing surfaces of each story within the checked and adjusted segment | 12 + 2 n |
| NOTE: n – story number | |
4.4. Production and installation of walls
4.4.1. Permissible deviations from the design dimensions of wall panels, partitions, floor slabs are specified in Table 18.
Table 18 – Permissible deviations from the design dimensions of wall panels, partitions, floor slabs
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviations of precast panels when the total length of the panel is 6 m and below: | |
| – In length | ± 10 |
| – In width | ± 8 |
| – In thickness | ± 4 |
| 2. Deviations of precast panels when the length is greater than 6 m: | |
| – In length | ± 15 |
| – In width | ± 10 |
| – In thickness | ± 4 |
4.4.2. Permissible deviations when assembling wall panels and partitions of residential buildings and public works are specified in Table 19.
Table 19 – Permissible deviations when assembling wall panels and partitions of residential buildings and public works
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the axis of wall panels and partitions at the bottom section from the reference axis | ± 5 |
| 2. Deviation of the plane of the wall panel or partition from the vertical (at the top section) | ± 5 |
| 3. Difference in elevation of the bearing surface of the panel within the adjusted part | ± 10 |
4.4.3. Permissible deviations when producing and assembling beams, trusses are specified in Table 20.
Table 20 – Permissible deviations when producing and assembling beams
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Permissible deviation from the design when producing trusses with spans up to 18 | |
| – Length | ± 10 |
| – Width | ± 5 |
| – Height | ± 5 |
| 2. Permissible deviation from the design when producing trusses with spans greater than 18 m | |
| – Length | ± 20 |
| – Width | ± 5 |
| – Height | ± 5 |
| 3. Permissible deviation from the design when producing beams with spans up to 6 m: | |
| – Length | ± 10 |
| – Width | ± 10 |
| – Height | ± 5 |
| 4. Permissible deviation from the design when producing beams with spans greater than 6 m: | |
| – Length | ± 10 |
| – Width | ± 10 |
| – Height | ± 5 |
5. Masonry works
5.1. Rubble stone and rubble concrete masonry
Permissible deviations from the design dimensions of foundation masonry, walls, columns made of rubble stone and rubble concrete are specified in Table 21.
Table 21 – Permissible deviations from the design dimensions of foundation masonry, walls, columns made of rubble stone and rubble concrete
Dimensions in millimeters
| Deviation name | Permissible deviation | ||
| Foundation | Walls | Columns | |
| 1. Dimensional deviation in | |||
| – Thickness | – | – 10 | – 10 |
| + 30 | + 20 | + 20 | |
| – Story elevation (top of masonry) | – 25 | – 15 | – 15 |
| – Width of the wall panel between opening | – | – 20 | – |
| – Width of door openings | – | + 20 | – |
| – Deviation of the axis of adjacent window openings | – | ± 20 | – |
| – Deviation of the structure axi | ± 20 | ± 15 | ± 10 |
| 2. Deviation of the plane and angle of masonry from the vertical: | |||
| – Calculated for 1 story | – | 20 | 15 |
| – Calculated for the entire building | 20 | 30 | 30 |
| 3. Horizontal deviation over a length of 10 m of masonry | 30 | 20 | – |
| 4. Roughness on the vertical plane surface of the masonry when checked with a 2 m long ruler: | |||
| – On the surface to be plastere | – | 15 | 15 |
| – On the surface not to be plastered | 20 | 15 | 15 |
| NOTE: The vertical and horizontal of a masonry must be checked at 2 positions per 1 m of height. The result is taken as the average of the deviations of the 2 checks. | |||
5.2. Dressed stone, ashlar masonry
Permissible deviations are specified in Table 22.
Table 22 – Permissible deviations of dressed stone, ashlar masonry
Dimensions in millimeters
| Deviation name | Permissible deviation | ||
| Foundation | Walls | Columns | |
| 1. Dimensional deviation in thicknes | + 15 | + 15 | + 10 |
| 2. Roughness on the surface of unplastered stone masonry checked by pressing a 2 m long ruler against the masonry surface | ± 5 | ± 5 | ± 5 |
5.3. Masonry of fired bricks and unfired bricks with defined dimensions
Permissible deviations are specified in Table 23
Table 23 – Permissible deviations of masonry of fired bricks and unfired bricks with defined dimensions
Dimensions in millimeters
| Deviation name | Permissible deviation | ||
| Foundation | Walls | Columns | |
| 1. Dimensional deviation: | |||
| – Thickness | 15 | + 15 | ± 15 |
| – Top elevation of masonry and storie | – 15 | – 10 | – 15 |
| – Width of the wall panel adjacent to doors | – | – 15 | – |
| – Width of door opening | – | – 20 | – |
| – Deviation of the axis of adjacent window openings | – | + 20 | – |
| – Deviation of the structure axis | ± 10 | ± 10 | ± 10 |
| 2. Deviation of the plane and angle of masonry from the vertical: | |||
| – Deviation of the axis of adjacent window opening | – | 10 | 10 |
| – Deviation of the structure axi | 10 | 30 | 30 |
| 3. Deviation of the horizontal courses of masonry over a length of 10 m | 20 | 20 | – |
| 4. Roughness on the vertical plane surface of the masonry when checked with a 2 m long ruler: | |||
| – On the surface to be plastered | – | 10 | 5 |
| – On the surface not to be plastered | 5 | 5 | 5 |
| NOTE: 1) The verticality of the face and angle of masonry, the horizontality of the masonry courses must be checked per meter of masonry height and the deviations are averaged. If the deviations of the structure axis are greater than those specified in Table 23, they must be adjusted immediately at the elevation of the next floors and stories. 2) The deviation of the position of the truss supports in plan compared to the design position does not exceed 20 mm. | |||
5.4. Masonry shells – Domes made of fired bricks
Dimensional deviations of formwork when building double curvature shells compared to the design are specified in Table 24.
Table 24 – Dimensional deviations of formwork when building double curvature shells
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. For the rise at any point of it | 1/200 of the rise value |
| 2. Deviation of the formwork at the middle section from the vertical plane | 1/200 of the shell rise |
| 3. Span width of the shell | 10 |
| NOTE: These deviations do not apply to movable formwork when building undulating shells. | |
5.5. Masonry of concrete blocks, silicate blocks and processed slate
Permissible deviations for foundation masonry, walls, columns are specified in Table 25.
Table 25 – Permissible deviations for foundation masonry, walls, columns
Dimensions in millimeters
| Deviation name | Permissible deviation | ||
| Foundation | Walls | Columns | |
| 1. Deviation from the design dimensions: | |||
| – Thickness | 20 | ± 20 | ± 10 |
| – Top elevation of masonry and stories | – 20 | – 20 | – 20 |
| – Width of door openings | – | + 20 | – |
| – Deviation of the structure axes | 10 | 10 | 10 |
| 2. Deviation of the plane and angle of masonry from the vertical: | |||
| – Calculated for 1 story | – | 20 | 20 |
| – Calculated for the entire building | 30 | 30 | 30 |
| 3. Deviation of the horizontal courses of masonry over a length of 10 m | 20 | 20 | – |
| 4. Roughness on the vertical plane surface of the masonry when checked with a 2 m long ruler: | |||
| – On the surface to be plastered | – | 20 | 15 |
| – On the surface not to be plastered | 10 | 10 | 10 |
| NOTE: The verticality of the face and angle of masonry is checked per meter of masonry height and the above deviations are averaged. Deviations of each structure exceeding the above provisions must be adjusted immediately at the elevation of the floor slabs and at the next stories. | |||
6. Fabrication and installation of steel structures
6.1. Fabrication of steel structures
6.1.1. Permissible deviations of the diameter of high-precision bolt holes are specified in Table 26.
Table 26 – Permissible deviations of the diameter of high-precision bolt holes
Dimensions in millimeters
| Nominal hole diameter | Permissible deviation | |
| Upper side | Lower side | |
| – Greater than 12 to 18 | + 0.24 | 0 |
| – Greater than 18 to 30 | + 0.28 | 0 |
| – Greater than 30 to 39 | + 0.34 | 0 |
| NOTE: The diameter of the shank of high-precision bolts is specified by the diameter of the bolt hole, the deviations are also specified the same. | ||
6.1.2. Permissible deviations for rivet holes and bolt holes with low, medium precision and high-strength bolt holes are specified in Table 27.
Table 27 – Permissible deviations for rivet holes and bolt holes with low, medium precision and high-strength bolt holes
| Deviation name | Hole diameter (mm) | Permissible deviation (mm) | Permissible deviation per group of holes | ||
| Đối với thép For carbon steel % | For alloy steel | ||||
| Rivets % | Bolts % | ||||
| 1. Deviation of the diameter of holes for riveting and bolting | 17 | 0; +1 | Not limited | ||
| 2. Ovality (difference between hole diameters) | < 17 | 0; +1 | Not limited | ||
| 3. Hole edge protruding beyond the 1 mm dimension and cracking at the hole edg | – | – | Not allowed | ||
| 4. Misalignment between the holes in each part of the assembled package | |||||
| – From 1 mm and belo | – | – | 50 | 10 | 50 |
| – From 1 mm to 1.5 m | – | – | 10 | Not allowed | 10 |
| 5. Axis deviation below 3% of the thickness of the assembled package but not greater than 2 mm when riveting by machine and not greater than 3 mm when riveting by hand | Not limited | < 20 | Not limited | ||
| 6. Greater than the values mentioned above | Not allowed | Not allowed | |||
6.1.3. Permissible deviations of rivets are specified in Table 28.
Table 28 – Permissible deviations of rivets
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the axis of the rivet head and the rivet shank | 1/10 of the shank diameter |
| 2. Diameter of the rivet head compared to the design must not be less than | 1/10 of the shank diameter |
| 3. Depth of edge cutting (caused by riveting the head damaging the base steel around the foot of the riveted head) not greater than | 1,1 |
| 4. Inclination of the rivet axis compared to the axis perpendicular to the plane of the component | 3° of the component thickness at the connection and not more than 3 mm |
| 5. Frill of the rivet head not greater than: | |
| – Thickness | 3 |
| – Width | 1.5; – 3 |
| 6. Dimensional deviation of the shank when the rivet diameter is | |
| – Less than or equal to 17 mm | + 0.4; – 0.3 |
| – Greater than 17 mm | + 0.5; – 0.4 |
| 7. Shaking or shifting of the rivet head when tapping with a hammer for inspection | Không cho phép |
| 8. Rivet head not tight against the assembled package | A 0.2 mm thick probe cannot be inserted more than 2 mm under the head |
| 9. Cracks or fractures of the rivet he | Không cho phép |
6.1.4. Permissible deviations for welding are specified in Table 29.
Table 29 – Permissible deviations for welding
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. For butt welding (see Figure 1) | |
| – maximum value of the gap (a), not greater th | + 2 |
| – one edge higher than the other (b), not greater tha | – 1; + 2 |
| 2. For lap welding (see Figure 1) | |
| – Deviation in the value of (c), not greater tha | 5 |
| – Maximum value of the gap (d), not greater than | 2 |
| 3. For fillet welding | |
| – Maximum value of the gap (e), not greater than | 2 |
| 4. Deviation of the cross-section of the butt weld compared to the design dimensions: | |
| a) In the height of the weld | |
| – When the steel thickness is from 4 mm to 20 mm, not greater than | 1 |
| – When the steel thickness is greater than 20 mm, not greater than | 2 |
| b) In the width of the weld | |
| – When the steel thickness is from 4 mm to 6 mm, not greater than | 1 |
| – When the steel thickness is from 8 mm to 10 mm, not greater than | 2 |
| – When the steel thickness is from 12 mm to 20 mm, not greater thann | 2.5 |
| – When the steel thickness is greater than 20 mm, not greater than | 3 |
| 5. Deviation in the height of the fillet weld when lap welding or T-joint weldin | |
| – When the weld leg is from 4 mm to 6 mm, not greater than | 1 |
| – When the weld leg is from 10 mm to 12 mm, not greater than | 1.5 |
| – When the weld leg is from 14 mm to 18 mm, not greater than | + 2; – 1 |
| – When the weld leg is greater than 20 mm, not greater than | + 3; – 1 |
Figure 1 – Welding types
6.1.5. Permissible deviations in the dimensions of structural parts compared to the design are specified in Table 30.
Table 30 – Permissible deviations in the dimensions of structural parts compared to the design
Dimensions in millimeters
| Dimensions and technology of performing the operations | Permissible deviation | |||||||
| Dimension ranges | ||||||||
| under 1.5 | 1.5 to 2.5 | 2.5 to 4.5 | 4.5 to 9 | 9 to 15 | 15 to 21 | 21 to 27 | Over 27 | |
| I. Assembly parts: | ||||||||
| 1. Length and width of parts: | ||||||||
| a) Manual oxy cutting along the marked lin | 2.5 | 3 | 3.5 | 4 | 4.5 | 5 | – | – |
| b) Semi-automatic and automatic oxy cutting using templates or cutting machines along the marked line | 1.5 | 2 | 2.5 | 3 | 3.5 | 4 | – | – |
| c) Cutting by machines on the bed or in the production lin | 1 | 1.5 | 2 | 2.5 | 3 | 3.5 | – | – |
| d) Cutting by planing or milling | 0.5 | 1 | 1.5 | 2 | 2.5 | 3 | – | – |
| 2. Difference in length of the diagonals of welded steel plates: | ||||||||
| a) Butt weldin | – | – | 4 | 5 | 6 | – | – | – |
| b) Lap welding | – | – | 6 | 8 | 70 | – | – | – |
| 3. Distance between the centers of holes | ||||||||
| a) According to markings: | ||||||||
| – Edge holes | 2 | 2.5 | 2.5 | 3 | 3.5 | 4 | – | – |
| – Adjacent holes | 1.5 | – | – | – | – | – | – | – |
| b) According to the centerline or processed in the production line: | ||||||||
| – Edge hole | 1 | 1 | 1.5 | 2 | 2.5 | 4 | – | – |
| – Adjacent hol | 0.7 | – | – | – | – | – | – | – |
| II. Dimensions of prefabricated structural elements | ||||||||
| 1. Assembled on the bed according to bolt dimension | – | – | – | – | – | – | – | – |
| 2. Assembled on the bed mounted on a jig with positioning pins and on a copying rack with positioning pins | 2 | 2 | 3 | 5 | 7 | 8 | 9 | 10 |
| 3. Dimensions (length. width) between milled surfaces | 0.5 | 1 | 1.5 | 2 | 2.5 | 3 | 3.5 | 4 |
| 4. Width of bottom plates machined by rolling and welded during assembly: | ||||||||
| – Butt welding | – | – | – | 7 | 10 | 12 | – | – |
| – Lap welding | – | – | – | 11 | 13 | 19 | – | – |
| III. Distance between groups of holes: | ||||||||
| 1. When machining individual parts and assembling according to marked lines | 3 | 4 | 5 | 7 | 10 | 12 | 14 | 15 |
| 2. When machining individual parts and assembling using positioning pins | 2 | 2 | 3 | 5 | 7 | 8 | 9 | 10 |
| 3. When drilling using drill jig | 0.5 | 1 | 1.5 | 2 | 2.5 | 3 | 3.5 | 4 |
| NOTE: 1. Dimensions in I.1.c.d; l.2.a; III must be measured using a tape measure with accuracy class 2. Dimensions in other items must be measured using a tape measure with accuracy class 3.2 For edges in item I.1.a.d. a dimensional deviation of + 5 mm is allowed. | ||||||||
6.2. Assembly of steel structures
6.2.1. Permissible deviations of the reference axis of foundations and supports are specified in Table 31.
Table 31 – Permissible deviations of the reference axis of foundations and supports
Dimensions in millimeters
| Dimension between axes m | Permissible deviation | |
| Assembled on the bed according to bolt dimensions or on a jig with positioning pins | Milled at the bearing surface | |
| – Less than 9 | 3 | 2 |
| – Từ 9 to 15 | 4 | 2.5 |
| – Over 15 to 21 | 5 | 3 |
| – Over 21 to 27 | 6 | 3.5 |
| – Over 27 to 33 | 7 | 4 |
| – Greater than 33 | 5.5√n | 4√n |
| NOTE: n – number of measurements with a 20 m long tape measure; n = I/20 l – Distance between axes | ||
6.2.2. Permissible deviations of the foundation surface, supports, support axes of the structure and bolt positions are specified in Table 32.
Table 32 – Permissible deviations of the foundation surface, supports, support axes of the structure and bolt positions
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Top plane of the support: | |
| a) In height | ± 1,5 |
| b) In inclination | 1/1 500 |
| 2. Foundation surface: | |
| a) In height | ± 5 |
| b) In inclination | 1/1 000 |
| 3. Offset of the anchor bolt position when: | |
| a) Bolts within the suppor | 5 |
| b) Bolts outside the support | 10 |
| 4. Deviation of the elevation up to the end of the anchor bolt | + 20; – 0 |
| 5. Deviation of the length of the threaded part of the anchor bolt | + 30; – 0 |
6.2.3. Deviations when assembling steel structures of buildings and works are specified in Table 33.
Table 33 – Permissible deviations when assembling steel structures of buildings and works
Dimensions in millimeters
| Deviation name | Permissible deviation |
| I. Columns: | |
| 1. Deviation of the total height of the column: | |
| – When the column height is less than or equal to 10 m | 10 |
| – When the column height is greater than 10 m | 1/1000 of the column height, but not more than 15 mm |
| 2. Deviation of the cross-sectional dimension | 5 |
| 3. Offset of the column axis from the reference axis (at the column base section) | 5 |
| – When the column height is greater than 10 m | 1/1000 of the column height, but not more than 15 mm |
| 4. Offset of the column axis according to the vertical (at the column top section): | |
| – When the column height is less than or equal to 10 m | 10 |
| – When the column height is greater than 10 m | 1/1000 of the column height, but not more than 35 mm |
| 5. Curvature of the column | 1/1000 of the column height, but not more than 13 mm |
| 6. Deviation in the elevation of the bearing plane (column shoulder) | 5 |
| II. Trusses, beams and rafters | |
| 1. Deviation in the length (span) of the member | |
| – When the member is shorter than or equal to 25 m | 10 |
| – When the member is longer than 25 m | 1/2500 of the length, but not more than 30 m |
| 2. Deviation in height | 5 |
| 3. Deviation in the elevation of the bearing details of trusses and beam | 20 |
| 4. Deviation of the top chord (at midspan) from the vertical plane passing through the center of the 2 supports | 1/250 of the member height |
| 5. Curvature of the compression member relative to the plane of the truss | 1/1500 of its length but not greater than 10 mm |
| 6. Deviation in the spacing between members (beams, trusses) | 5 |
7. Timber structures and works
7.1. The gap of the joints of the main members in load-bearing timber structures must not be greater than 1 mm.
7.2. Permissible deviations from the design dimensions when fabricating and assembling load-bearing timber structures (main beams, rafters…) are specified in Table 34.
Table 34 – Permissible deviations from the design dimensions when fabricating and assembling load-bearing timber structures
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation in the length of the member: | |
| – When the length of the member is less than or equal to 15 m | 20 |
| – When the length of the member is greater than 15 m | 30 |
| 2. Deviation in the height of the member: | |
| – When the span of the member is less than or equal to 15 | 10 |
| – When the span of the member is greater than 15 m | 20 |
| 3. Deviation in the spacing between the joints of the member, not greater than | 5 |
| 4. Deviation in the depth of oblique tenons | 2 |
| 5.Deviation in the spacing between the centers of pins | |
| – Inlet hole | 2 |
| – Outlet hole across the wood grain | 10 (but not greater than 4% of the wood thickness) |
| – Outlet hole along the wood grain | 10 (but not greater than 4% of the wood thickness) |
| 6. Sai số khoảng cách giữa tim của các đinh (phía đóng đinh) | 2 (nhưng không lớn hơn đường kính của đinh) |
7.3. Permissible deviations of timber structures during erection (beams, rafters…) are specified in Table 35.
7.4. Permissible deviations of walls, beams of buildings and works made of sawn timber or logs compared to the design position are specified in Table 36.
Table 35 – Permissible deviations of timber structures during erection
Dimensions in millimeters
| Tên sai số | Sai số cho phép |
| 1. Deviation of the axis of the members | 20 |
| 2. Deviation of the member from the vertical | 5% of the member height but not more than 15 mm |
| 3. Deviation of each member or compression part compared to the design | 1/300 of the length of the part or compression part |
| 4. Deviation of walls and partitions from the vertical of each story | 10 |
| 5. Deviation of the underside of the roof in the horizontal direction: | |
| – Per 1 m length of the beam | 2 |
| – Over the entire bay | 10 |
| 6. Deviation of the plane of the truss in the vertical direction | 1% of the truss height |
Table 36 – Permissible deviations of timber structures during erection
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the battens of sawn timber walls from the horizontal per 1 m length | 5 |
| 2. Deviation of the battens of log walls supporting floor beams from the horizontal per 1 m length | 5 |
| 3. Deviation of the wall from the vertical per 1 m | 5 |
| 4. Deviation in the spacing between floor beams: | |
| – In case of using timber planks for underlayment and decking | ± 10 |
| – In case of using other materials for underlayment | ± 20 |
8. Floor works
8.1. Subgrade under floors
8.1.1. The roughness of the subgrade surface (checked with a 2 m long ruler) must not be greater than 20 mm.
8.1.2. The deviation of the subgrade surface from the horizontal plane or from the determined allowable slope must not be greater than 0.2% of the corresponding room dimension. When the room has a width or length of 25 m or more, that deviation must not be greater than 50 mm.
8.2. Underlayment layer
8.2.1. Permissible deviations of the underlayment surface compared to the plane of the 2 m long checking ruler (or template ruler) are specified in Table 37.
Table 37 – Permissible deviations of the underlayment surface
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Underlayment layer made of sand, gravel, slag, crushed stone, clay, compacted pebbles | ± 20 |
| 2. Underlayment layer made of concrete | ± 10 |
8.2.2. The deviation of the underlayment surface from the horizontal plane or from the determined slope must not be greater than 0.2% of the corresponding room dimension. When the room has a width or length of 25 m or more, that deviation must not be greater than 50 mm.
8.3. Bedding layer
8.3.1. Permissible deviations of the bedding surface compared to the plane of the 2 m long checking ruler (or template ruler) are specified in Table 38.
Table 38 – Permissible deviations of the bedding surface compared to the plane of the 2 m long checking ruler
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. When paving with plastics (in the form of sheets or rolls) | 2 |
| 2. When paving with construction materials, other sheets and bricks with a mastic intermediate layer, when paving a layer of glass bricks | 3 |
8.3.2. The deviation of the bedding surface from the horizontal plane or from the determined allowable slope must not be greater than 0.2% of the corresponding room dimension, but not greater than 50 mm when the width or length of the room is 25 m or more.
8.4. Finishing (surfacing) layer
8.4.1. The deviation of the surfacing layer from the horizontal plane or from the specified allowable slope must not be greater than 0.2% of the corresponding room dimension, when the room has a width or length of 25 m or more, but that deviation must not be greater than 50 mm.
8.4.2. The gap between the surfacing layer and the surrounding floor structures must not be greater than 2 mm.
8.4.3. There must be no cracks, chipping, and gaps between the skirting and the surfacing layer or the wall.
8.4.4. The deviation in the thickness of the surfacing layer compared to the design at a few places must not be greater than 10% (checked during the construction process)
8.4.5. Permissible deviations of the surfacing compared to the plane of the 2 m long checking ruler (or template ruler) are specified in Table 39.
Table 39 – Permissible deviations of the surfacing compared to the plane of the 2 m long checking ruler
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Gravel and slag surfacing | 10 |
| 2. Bituminous crushed stone slab surfacing | 10 |
| 3. Soil cement surfacing | 10 |
| 4. Sand-cement concrete surfacing | 4 |
| 5. Heat-resistant, acid-resistant concrete surfacing | 4 |
| 6. Asphalt concrete surfacing | 6 |
| 7. Plastic surfacing (in the form of sheets, rolls) | 2 |
8.5. Cobblestone surface
8.5.1. The thickness of the sand bedding layer after compaction must not be less than 60 mm. Stones are arranged in patterns and embedded into the sand bedding layer not less than 1/3 of the stone height.
8.5.2. Permissible deviations of the cobblestone paving surface are specified in Table 40.
Table 40 – Permissible deviations of the cobblestone paving surface
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the cobblestone paving surface from the plane of the 2 m long checking ruler (or template ruler) | 10 |
| 2. Depression between 2 adjacent stones | 3 |
| 3. Deviation of the joints between rows on the paving surface from the straight line | 10 mm / 10 m length |
8.6. Paving surface made of dressed stone, bricks or slabs
8.6.1. The thickness of the bedding layer made of cement-sand mortar must not be greater than 15 mm. The thickness of the bituminous bedding layer must not be greater than 3 mm.
8.6.2. Permissible deviations for the paving surface made of dressed stone and bricks are specified in Table 41.
Table 41 – Permissible deviations for the paving surface made of dressed stone and bricks
Dimensions in millimeters
| Deviation name | Permissible deviation | |
| Dressed stone paving | Brick paving | |
| 1. Deviation of the paving surface from the checking plane using a 2 m long level ruler | 10 | 6 |
| 2. Roughness between 2 stones at a distance on the paving surface | Not greater than 3 | Not greater than 2 |
| 3. Settlement of the paving surface on the mastic, bituminous bedding layer, under a concentrated load of 200 kg (compression section: 30 x 30, compression time: 40 h) | Not greater than 1.5 mm, at the same time the mastic must not rise to the paving surface through the joints | |
| 4. Deviation between 2 laid rows from the straight direction over a 10 m length of the row | Not greater than 10 mm | |
| 5. Paving slabs with broken corners, cracks, chipping, debonding | Not allowed | |
8.6.3. Permissible deviations for the paving surface made of various types of slabs are specified in Table 42.
Table 42 – Permissible deviations for the paving surface made of various types of slabs
Dimensions in millimeters
| Tên Deviation namesố | Permissible deviation |
| 1. Permissible deviation of the paving surface from the checking plane using a 2 m long ruler | 4 |
| 2. Roughness between 2 paving slabs at a distance, not greater than | 2 |
| 3. Joint deviation from the straight line over a straight section of 10 m | 10 |
| 4. Deviation of the paving surface from the horizontal or specified slope | |
| – Calculated as the corresponding percentage, % | 2 |
| – Section with a length or width of the building equal to 25 m | 50 |
| 5. Maximum thickness of paving joints | |
| – Slab dimensions less than or equal to 200 mm | 2 |
| – Slab dimensions greater than 200 mm | 3 |
8.6.4. Permissible deviations of the horizontal paving surface (on mortar or on sand) are specified in Table 43.
Table 43 – Permissible deviations of the horizontal paving surface (on mortar or on sand)
Dimensions in millimeters
| Deviation name | Permissible deviation | |
| Dressed stone paving | Brick paving | |
| 1. Deviation of the paving surface from the checking plane using a 2 m long ruler | 6 | 8 |
| 2. Roughness between 2 adjacent slabs, not greater than | 2 | |
| 3. Gap between 2 transverse slabs laid on sand, not greater than | – | 3 |
| 4. Joint deviation from the straight line between rows over a 10 m length, not greater than | 10 | |
8.7. Wooden flooring and parquet flooring
8.7.1. Permissible deviations of the connection between the skirting and the floor are specified in Table 44.
Table 44 – Deviations of the connection between the skirting and the floor
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Gap between floorboards and walls or partitions (with skirting)1. Khe hở giữa ván sàn và tường hay tường ngăn (có ốp chân tường) | 15 |
| 2. Gap between the skirting board and the floor | 1 |
8.7.2. Permissible deviations for wooden flooring surfaces and parquet flooring surfaces are specified in Table 45.
Table 45 – Permissible deviations for wooden flooring surfaces and parquet flooring surfaces
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the floor surface from the checking plane using a 2 m long level ruler | 2 |
| 2. Roughness between the edges of 2 tightly joined boards | not allowed |
| 3. Gap between 2 boards (at individual locations) with wooden flooring, not greater than | 1 |
9. Roofing works
9.1. Roof coverings
9.1.1. Permissible deviations of the roof supporting structure are specified in Table 46.
Table 46 – Permissible deviations of the roof supporting structure
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Dimensional deviation compared to the design | |
| – Spacing between structure axes | 20 |
| – Structure height | 10 |
| 2. Offset of splice plates placed at supports | 10 |
| 3. Vertical deviation when placing the structure | 0.5% calculated by height |
| 4. Surface of the roof supporting structure | |
| – When covering with oiled paper, checked with a 3 m long ruler | |
| + Along the slope | 5 |
| + Across the slope | 10 |
| – When covering with machine-made tiles, fiber cement sheets, checked with a 1 m long ruler: | |
| + Along the slope | 5 |
| + Across the slope | 5 |
| – When covering with metal roofing sheets: | |
| + Along the slope | 5 |
| + Across the slope | 5 |
9.1.2. Permissible deviations when covering roofs with fiber cement sheets are specified in Table 47.
Table 47 – Permissible deviations when covering roofs with fiber cement sheets
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Bottom edge of the sheet compared to the horizontal | ± 6 |
| 2. Fiber cement sheets of the upper row overlapping the lower row in length | ± 10 |
| 3. Profiled fiber cement sheets overlapping each other | ± 10 |
| 4. Deviation from the specified slope | 5 |
| 5. Improper nailing or screwing | – |
9.1.3. Permissible deviations when covering roofs with machine-made tiles are specified in Table 48.
Table 48 – Permissible deviations when covering with machine-made tiles
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Gap between 2 tiles (channel tiles) | not allowed |
| 2. Roughness of the roof surface checked with a 3 m long ruler (measured at the top of the pan foot) | |
| – Along the slope | 5 |
| – Across the slope | 5 |
| 3. Deviation of the slope compared to the design | 5% |
| 4. Bottom row of battens not properly aligned | not allowed |
| 5. Tile pan foot not pressing against the batten | not allowed |
| 6. Improper tying of tiles | not allowed |
9.2. Flat roofs
Permissible deviations when constructing flat roofs are specified in Table 49.
Table 49 – Permissible deviations when constructing flat roofs
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the slope compared to the design | ± 5 |
| 2. Deviation of the roof surface checked with a 3 m long ruler, not more than 1 location per 1 m | 5 |
9.3. Flat roofs made of precast concrete slabs placed on reinforced concrete rafters
9.3.1. The minimum thickness of the cement mortar layer at the welds and the metal parts connecting the rafters must not be less than 20 mm.
9.3.2. Permissible deviations when constructing flat roofs made of precast concrete slabs placed on reinforced concrete rafters are specified in Table 50.
Table 50 – Permissible deviations when constructing flat roofs
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the elevation of the support for placing the rafter trusses | ± 5 |
| 2. Deviation of the position of installing reinforced concrete components compared to the design | 5 |
| 3. Deviation of the roof surface checked with a 3 m long ruler: | |
| – Along the slope | 3 (not more than 1 location/1 m) |
| – Across the slope | 10 (not more than 1 location/1 m) |
10. Finishing works
10.1. Plastering works
Permissible deviations in mortar plastering works are specified in Table 51.
Table 51 – Permissible deviations in mortar plastering works
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Roughness of the plaster surface (detected by a 2 m long float or ruler) | not more than 3 locations with depressions up to 3 mm |
| 2. Deviation of the surface from the vertical over the entire room height: | |
| – Per 1 m height | 10 |
| – Over the entire room height | 15 |
| 3. Deviations of the surface from the horizontal: | |
| – Per 1 m length | 3 |
| – Over the entire length | 10 |
| 4. Blistering plaster layer (checked by light tapping, detecting a hollow sound) | not allowed |
| 5. Back surface with cracks, missing areas not plastered | not allowed |
| 6. Deviation of window sills, door openings, columns, protruding wall parts from the horizontal and vertical | |
| – Per 1 m length | 5 |
| – Over the entire structure | 10 |
| 7. Deviation of the radius of curvature of curved surfaces and moldings compared to the design | ± 15 |
10.2. Natural stone cladding
10.2.1. Permissible deviations when cladding exterior surfaces with natural stone are specified in Table 52.
Table 52 – Permissible deviations when cladding exterior surfaces with natural stone
Dimensions in millimeters
| Deviation name | Permissible deviation | ||
| Polished surface | Honed surface | Hard stone surface | |
| 1. Thickness of mortar joints | 0.5 | 1 | 2 |
| 2. Deviation of the cladding surface from the vertical: | |||
| – Per 1 m height | 2 | 3 | – |
| – Over the entire story height | 5 | 10 | – |
| 3. Deviation of joints from the horizontal or vertical: | |||
| – Per 1 m joint length | 2 | 3 | 3 |
| – Over the entire joint lengt | 3 | 5 | 10 |
| 4. Deviation of the connection of decorative parts | 1 | 2 | – |
| 5. Deviation of the edges of 2 adjacent slabs | 1 | 1 | 2 |
10.2.2. Permissible deviations when cladding interior surfaces with natural stone are specified in Table 53.
Table 53 – Permissible deviations when cladding interior surfaces with natural stone
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the cladding surface from the vertical plane: | |
| – Per 1 m heigh | 2 |
| – Over the entire cladding height | 5 |
| 2. Deviation of joints from the horizontal and vertical:: | |
| – Per 1 m height | 2 |
| – Over the entire row lengt | 3 |
| 3. Deviation of the edges of adjacent cladding slabs | 3 |
10.3. Cladding works with artificial materials
10.3.1 General requirements: The structure of vertical cladding with ceramic tiles must ensure that water does not penetrate through the joints of the cladding parts. The joints between the cladding slabs must be straight and flat. Cracks on the slab edges and broken corners must not exceed 5 mm.
10.3.2 Permissible deviations when cladding exterior surfaces with artificial slabs are specified in Table 54.
Table 54 – Permissible deviations when cladding exterior surfaces with artificial slabs
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the cladding surface from the plane of the 2 m long checking ruler | 3 |
| 2. Width of the gap between the cladding surface and the window sill, door frame, between the cladding surface and the architectural molding | 10 |
| 3. Chipping at the corners of the cladding slab | 5 |
| 4. Deviation of the surface and angle between 2 surfaces from the vertical: | |
| – Per 1 m length | 2 |
| – Over the entire story | 5 |
| 5. Voids between the cladding surface and the wall | not allowed |
10.3.3 Permissible deviations in interior cladding works with artificial slabs are specified in Table 55.
Table 55 – Permissible deviations in interior cladding works with artificial slabs
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Maximum thickness of mortar joints: | |
| – Between slabs with dimensions of 200 x 200 mm or larger | 3 |
| – Between slabs with dimensions less than or equal to 200 x 200 mm | 2 |
| – At protruding parts (with all slabs) | 3 |
| 2. Deviation of the surface from the plane of the 2 m long checking ruler | 2 |
| 3. Deviation of mortar over a 1 m length | 2 |
10.4. Glazing works
10.4.1. After installation, the glass must be tight, not warped, misaligned, not convex or concave, not gapped. The putty surface must be hard, flat, smooth, tight at the ends, not cracked or broken, not blistering. The glass ends and iron clamps must not protrude from the putty surface.
10.4.2. Permissible deviations when installing glass are specified in Table 56.
Table 56 – Permissible deviations when installing glass
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Cracking and delamination of putty when dry | not allowed |
| 2. The interface between the putty and the glass is rough and not parallel to the edge of the installation groove, pins and nails protruding outside the putty strip | not allowed |
| 3. Putty, mortar, oil, and paint stains on the glass surface | not allowed |
11. Installation of water supply – drainage pipes and sanitary equipment
11.1. Permissible deviations for reserved holes and trenches for installing pipes and sanitary equipment are specified in Table 57.
Table 57 – Permissible deviations for reserved holes and trenches for installing pipes and sanitary equipment
Dimensions in millimeters
| Deviation name | Permissible deviation | |
| Brick buildings | Prefabricated buildings | |
| 1. Axis of the hole in the floor slab compared to the vertical axis of the pipe | ± 10 | ± 10 |
| 2. Axis of the hole for anchor bolts in the foundation for placing sanitary technical equipment | ± 10 | ± 10 |
| 3. Top elevation of the foundation (excluding the bedding layer) for placing sanitary technical equipment | – 30 | – 30 |
11.2. Installation of domestic water supply pipes
11.2.1. Permissible deviations in the fabrication of pipe joints and parts are specified in Table 58.
Table 58 – Permissible deviations in the fabrication of pipe joints and parts
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Straight dimension of pipe parts compared to the specification | 2 |
| 2. Deviation of the straight dimension of fabricated pipe joints | 4 |
| 3. Reduction of the pipe length when bending compared to the specification | 15% |
| 4. Ovality of the cross-section at the bend (ratio of the difference between the largest and smallest outer diameters to the outer diameter of the pipe) | 10% |
11.2.2. Permissible deviations when welding pipes
- Edge misalignment when butt welding pipes: 10% of the pipe wall thickness
- Permissible deviation of the gap between two pipe ends when butt welding is specified in Table 59.
Table 59 – Permissible deviations when welding pipes
Dimensions in millimeters
| Pipe wall thickness | Permissible deviation | |
| Thermal welding | Gas welding | |
| – Under 2.5 | 0.5 | 0.5 to 1 |
| – From 2.5 to 3.5 | 0.5 to 1 | 1.0 to 1.5 |
| – Over 3.5 to 5 | 1.0 to 1.5 | 1.5 to 2 |
11.2.3. Permissible deviations when installing interior water supply equipment are specified in Table 60.
Table 60 – Permissible deviations when installing interior water supply equipment
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the standpipe when installing exposed branch pipes from the vertical line (per 1 m pipe length) | 2 |
| 2. Deviation in the distance between the standpipe and the wall surface compared to the specified distance | 5 |
| 3. Deviation in the installation height of the faucet on the sink, bathtub in the bathroom compared to the specified dimension | ± 10 |
| 4. Deviation in the installation height of the fire hydrant (specified height is 1.35 m | ± 20 |
11.2.4. Permissible deviations when installing vertical pipes of the domestic drainage system are specified in Table 61.
Table 61 – Permissible deviations when installing vertical pipes of the domestic drainage system
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the pipe axis in the vertical direction (per 1 m of pipe) | ± 2 |
| 2. Deviation of the distance between the pipe and the wall | ± 5 |
| 3. Axis deviation of the pipe compared to the design due to jointing | ± 5 |
11.2.5. Permissible deviations when installing sanitary equipment are specified in Table 62.
Table 62 – Permissible deviations when installing sanitary equipment
Dimensions in millimeters
| Deviation name | Permissible deviation | |
| Khi lắp đặt từng thiết bị | Khi lắp hàng loạt | |
| 1. Sink (to the sink edge) | ± 20 | ± 5 |
| 2. Water tank for toilet bowl (to the tank bottom): | ||
| – High-mounted tank | ± 20 | ± 5 |
| – Low-mounted tank | ± 10 | ± 5 |
| 3. Floor-mounted toilet bowl (to the bowl edge) | 20 | 5 |
| 4. Wall-mounted urinal (to the bowl edge) | 20 | 5 |
| 5. Bidet (opening edge) | 10 | 5 |
| 6. Flushing pipe for urinal trough (from the trough to the pipe axis) | 20 | 5 |
| 7. Toilet bowl (to the edge) | 20 | 5 |
| 8. Bathtub (to the edge) | 20 | 5 |
11.3. Installation of technological pipelines in works
11.3.1. Permissible deviations of the pipe supporting structure compared to the design are specified in Table 63.
Table 63 – Permissible deviations of the pipe supporting structure compared to the design
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Plan of the pipeline inside the building | ± 5 |
| 2. Plan of the pipeline outside the building | ± 10 |
| 3. In elevation | – 10 |
| 4. Slope, ‰ | 1 |
11.3.2. Permissible pipe wall misalignment and edge misalignment when butt welding joints, welding parts and sheets of carbon steel pipelines with a conventional pressure below 10 MPa are specified in Table 64.
Table 64 – Permissible pipe wall misalignment and edge misalignment when butt welding joints
Dimensions in millimeters
| Thickness of the connected component | Permissible pipe wall misalignment or edge misalignment |
| – From 3 to 4 | 1.0 |
| – From 5 to 6 | 1.5 |
| – From 7 to 8 | 2.0 |
| – From 9 to 14 | 2.5 |
| – From 15 and above | 3.0 |
| NOTE: In other cases of welding steel pipes, the permissible deviation of pipe wall misalignment or edge misalignment of the connected components must be taken as 10% of the pipe wall thickness but not more than 3 mm. | |
Permissible deviations in welding technological pipelines are specified in Table 65.
Table 65 – Permissible deviations in welding technological pipelines
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Having cracks (any size) | not allowed |
| 2. Lack of fusion: | |
| – Pipe thickness not greater than 20 mm | 15% of pipe thickness |
| – Pipe thickness over 20 mm | 3 |
| 3. Slag inclusion and porosity | |
| – Pipe thickness not greater than 20 mm | 10% of pipe thickness |
| – Pipe thickness over | 3 |
| 4. Impurities and mesh-like porosity (regardless of depth) | not allowed |
11.3.3. Permissible local edge misalignment at the joint when installing steel pipes is specified in Table 66.
Table 66 – Permissible local edge misalignment at the joint when installing steel pipes
Dimensions in millimeters
| Deviation name | Permissible deviation |
| – Local edge misalignment in the joint not exceeding 1/3 of the circumference: | Over a length of |
| + Pipe thickness under 5 mm | 2 |
| + Pipe thickness from 6 mm to 7 mm | 3 |
| + Pipe thickness over 7 mm | 4 |
11.3.4. Permissible deviation when installing cast iron pipes: the deviation from the vertical axis of the pipe of the steel joint in any direction must not be greater than 1 mm per 1 m of pipe length.
11.3.5. Permissible deviation when installing plastic pipes: The pipe wall misalignment and edge misalignment of the welded components (in the case of butt welding) must not be greater than 15% of the pipe wall thickness and not greater than 1 mm.
12. Other works
12.1. Ventilation and air conditioning equipment
12.1.1. Permissible deviations in the fabricated dimensions of air ducts and shaped parts for ventilation and air conditioning equipment are specified in Table 67.
Table 67 – Permissible deviations in the fabricated dimensions of air ducts and shaped parts
Dimensions in millimeters
| Deviation name | Permissible deviation |
| Outer diameter of round ducts or long side of rectangular ducts: | Compared to the outer diameter or side of the air duct |
| 100, 115, 130, 140, 150, 165 | ± 2.5 |
| 196, 215, 235, 269 | ± 3.0 |
| 285, 320 | ± 3.5 |
| 375, 440, 495 | ± 4.0 |
| 545, 595 | ± 4.5 |
| 660, 775 | ± 5.0 |
| 885, 1 025 | ± 5.5 |
| 1 100, 1 200 | ± 6.0 |
| 1 325, 1 425, 1 540 | ± 6.5 |
12.1.2. Permissible deviation when installing metal air ducts from the vertical (per 1 m height) is 3 mm.
12.1.3. Permissible deviation of the internal dimensions of gypsum slag and slag concrete boxes compared to the design when constructing pipes and air ducts made of fiber cement, concrete, slag concrete, and gypsum slag (as a percentage): 3%.
12.1.4. Permissible deviation of the gap between the edge of the front disc of the impeller and the edge of the suction hood of the centrifugal fan is 1% of the impeller diameter.
12.1.5. Permissible deviations when testing, adjusting, and accepting ventilation and air conditioning systems are specified in Table 68.
Table 68 – Permissible deviations when testing, adjusting, and accepting ventilation and air conditioning systems
Deviation name Permissible deviation
| Deviation name | Permissible deviation |
| 1. Deviation from the design-specified indicators and the volume of air passing through the air discharge and intake devices | ± 10 % |
| 2. Deviation from the design-specified indicators and the volume of air for exhaust and air transport systems | ± 10 % |
| 3. Deviation from the standard-specified indicators for the intake air temperature | ± 2 °C |
12.2. Construction of garbage chutes
12.2.1. General requirements
- Determine the suction in the pipe by dry suction when the garbage inlets and the garbage collection box doors are closed;
- No air suction through the closed garbage inlet gaps, checked by placing a candle flame near the door gap;
- Check the operation of the pipe cleaning winch by hooking and lowering it 3 times in the pipe.
12.2.2. Permissible deviations when constructing garbage chutes are specified in Table 69.
Table 69 – Permissible deviations when constructing garbage chutes
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Permissible deviation of the axis of the garbage chute from the vertical per 1 m height. | 2 |
| 2. Permissible deviation of the axis of the garbage chute from the vertical over the entire height | 25 |
12.3. Stoves and chimneys
Permissible deviations are specified in Table 70.
Table 70 – Permissible deviations when installing stoves and chimneys
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Deviation of the masonry surface from the vertical line (per 1 m height | 2 |
| 2. Deviation of surface roughness | |
| – For unlined stoves and chimneys | 2 |
| – For stoves lined with glazed tiles | 2 |
| 3. Deviation in the plan dimensions of the stove or chimney compared to the design | ± 1 % |
12.4. Insulation works
12.4.1. General requirements
- Pipes installed in trenches with covers and walkable tunnels must be insulated before covering with slabs, if installed in non-walkable tunnels, they must be insulated before installing the wall panels.
- The surface of the insulation layer must be flat, smooth, and tight. The gap between the 3 m long checking ruler and the surface of the insulation layer must not exceed 10 mm.
12.4.2. Permissible deviation of the total thickness of the insulation layer compared to the design is 10%.
13. Electrical lighting installation works
13.1. General requirements
- The strength of the hooks (for hanging ceiling fans, lighting fixtures in the room…) must be load-tested. The mechanical stress in the fixtures holding the lighting equipment must be less than 3 times the allowable stress in the structural parts of the lighting equipment;
- Steel supports, cables, casings, bars, and clamping parts must be rust-proofed (galvanized). Glass lamp shades must be securely held, the hanging points for ceiling fans and pendant lights must be covered;
- Electrical panels must be installed in accordance with the design requirements and firmly attached to the wall. Fuses must be installed according to the standard.
13.2. Permissible deviations when performing electrical works are specified in Table 71.
Table 71 – Permissible deviations when performing electrical works
Dimensions in millimeters
| Deviation name | Permissible deviation |
| 1. Wiring on the wall surface compared to the vertical and horizontal lines (per 1 m length) | 5 |
| 2. Deviation in the installation height of lighting equipment (from the floor surface): | |
| – Switch height (1.6 m) | ± 50 |
| – Electrical outlet height (0.9 m) | ± 50 |
| – Meter height (1.5 m) | ± 50 |
| NOTE: When assessing the quality of the installation work, the electrical measurement results must also be considered. | |