In construction whether vertical or horizontal there is what we always keep in mind that so called “Tolerance” I am going to post it here in order to easily for you to find, if you can’t remember because there are too many of them, and if you want to read again just simply bookmark the post or make this on your favorites.
Firstly, here is the meaning of “Tolerance” – is the permissible limit or limits of variation of physical dimension, a measured value or physical property of a material or manufactured object.
Variation in Concrete
| 1. Variation from the plumb | ||
|---|---|---|
| 1.1 | In the lines and surfaces of columns, walls and in arises | |
| Area | Tolerance | |
| In any story or 6 meter max. | 6mm | |
| In 12 meter or more | 10mm | |
| 1.2 | For exposed corner column, control joints, grooves and other conspicuous lines | |
| In any story or 6 meter max. | 6mm | |
| In 12 meter or more | 12mm | |
| 2. Variation from the level or from the grade indicated on the drawings | ||
|---|---|---|
| 2.1 | From level around perimeter of the building, at stairs and similar critical locations, shall not vary from more than +/- 10mm from level shown on the drawings. | |
| 2.2 | In floors, ceiling, beam soffit and arises maximum difference between any two points. | |
| Area | Tolerance | |
| In 3 meter | 4mm | |
| In any bay or 6 meter max. | 6mm | |
| In 12 meter or more | 12mm | |
| 2.3 | For exposed lintels, sills, horizontal grooves and other conspicuous lines | |
| In any bay or 6 meter max. | 6mm | |
| In 12 meter or more | 10mm | |
| 3. Variation in plan dimensions from the established building gridlines to related columns, walls and partition. | ||
|---|---|---|
| Area | Tolerance | |
| In any bay or 6 meter max. | 6mm | |
| In 12 meter or more | 10mm | |
| 4. Variation in the size and location of the sleeves, floor and wall openings 6mm. | ||
| 5. Variation in cross-sectional dimensions of columns and beams, and in the thickness of slabs and walls | ||
|---|---|---|
| Area | Tolerance | |
| Minus | 6mm | |
| Plus | 12mm | |
| 6. Footings | ||
|---|---|---|
| 6.1 | Variation in plan dimensions | |
| Area/Description | Tolerance | |
| Minus | 6mm | |
| Plus | 12mm | |
| 6.2 | Misplacement or eccentricity | |
| 2% of the footing width in the direction of misplacement but not more than 50 mm. | ||
| 6.3 | Variation in thickness | |
| Area/Description | Tolerance | |
| Decrease | 5% of the thickness but not more than 25mm | |
| Increase | No limit | |
| 7. Variation in steps | ||
|---|---|---|
| 7.1 | In plight of stairs | |
| Area/Decription | Tolerance | |
| rise | 3mm | |
| tread | 3mm | |
| 7.2 | In consecutive steps | |
| rise | 2mm | |
| tread | 3mm | |
Tolerances in placements of reinforcement
| 1 | Clear distance | |
|---|---|---|
| Area/Description | Tolerance | |
| 1.1 | to formed soffit | - 6mm |
| 1.2 | to other formed surfaces | +/- 6mm |
| 2 | Minimum spacing between bars | -6 mm |
| 3 | Clear distance from unformed surface to top reinforcement | |
| 3.1 | members 200mm deep or less | +/- 6mm |
| 3.2 | members more than 200mm deep but less than 600mm deep | - 6mm +12mm |
| 3.3 | members 600mm deep or greater | -6mm +25mm |
| 4 | Longitudinal locations of bends and ends of reinforcement | |
| 4.1 | General | +/- 50mm |
| Discontinuous ends | +/- 12mm | |
| 5 | Length of bar laps and anchorage | -25mm |
That’s all I’ve read. if you have supplements to the above tolerances please feel free to comment or leave your reply below.
Thanks!
If possible please metion the Standard reference for the above tolerance
Hi! Mehboob Alam, you can see here few standard reference for the tolerances.
https://www.facebook.com/QAQCinConstruction/photos/a.558548510881940.1073741825.370218133048313/587911191279005/?type=1&theater