Construction Tolerance vs Legal Defect: Understanding Quality Check Disputes
Theme: Tendering to Execution; Module: Engineering & Site
Author: Dr. Pradeep Reddy Sarvareddy
Published Date: 22 Jan 2026
Disputes related to Quality Check could result in delayed payments or redoing the work, but which will cost a lot of money. Engineering includes certain “tolerance” which is a way of saying that certain degree of defects, or in other words “a degree of poor quality”, can be allowed. Understanding the Contract and Specifications, and their legal implications could win you the legal dispute. Let us explore how legal defence arises during quality inspections from the concept of tolerances during construction.
In law we have a doctrine of “reasonableness”. In Engineering we have its equivalent which is termed as “tolerance”.
Construction in the site is not like repeating a test in a laboratory. In a laboratory, 100 engineering samples could produce very similar quality, but in the site, 100 works may produce significantly different quality. The concept of “perfection” cannot be applied in construction. That is why the concept of tolerance exists in Construction.
Tolerance is the engineering equivalent for allowing errors or in other words “permitted deviations”. For example, if we say that a Man is 6 feet in height, are we saying exactly 6 feet but not 5 feet 11 inches or 6 feet 1 inch? In Engineering, if a floor height is said to be 10 feet, the actual height after construction could be plus or minus an inch or more, as per Code. These errors are known as Tolerance and are allowed as per Code. Tolerances are the engineering version of legal flexibility, but only when properly documented. Tolerances determine whether work is Good, Good Enough or Legally Defective.
But during constructions, someone may accept tolerances when convenient and ignore when not convenient. Contractors should be smart and record these details. Advocates should understand the concept and learn to protect the innocent Party.
Tolerances can be many types as follows:
- Dimensional Tolerances
- Placement Tolerances
- Performance Tolerances
Tolerances decide the following:
- If the work is acceptable
- If the payment is approved
- If the work must be redone
- If the contractor is blamed
- If the dispute is won or lost
One inch could cost you Lakhs or Crores. Tolerance then gets measured in “Rupees”. This is when people start noticing the aspect. Understand that all Tolerance are not the same. The kinds of Tolerance are as follows:
- Strict Tolerance
- Negotiable Tolerance
But as noted in the earlier Article related to Rounding, if there was some error during construction, go back to the Designer. May be the Designer could help after analysing the Tolerance.
The Contractor should note the following:
- Measure and document all work done
- Be present when the data is recorded
- Ensure the instruments are calibrated before measurements
- Involve an Advocate and understand the view from the other side
If an Advocate is involved in these disputes, check the following:
- Were the measurements taken only at the worst point or are the measurements an average of multiple values across various points (something like how thick is your finger)
- Tolerance applicable to one “part” of a structure need not be the same for other “parts” (something like the thickness of a ring finger is what you need to buy a ring, not the thickness of thumb)
- Double check all the information and process of the Contractor and the Department
- Involve an Engineer and get more details
Legal Reasonableness may not apply to Construction Tolerance. Understand both the Worlds.