MEP Design Review Before Tender: The 20 Checks That Save Variation Claims

A pre-tender MEP design review is a structured check of quantities, specifications, coordination, approvals readiness and tender documents before bidders price the job. Variation claims usually start from a gap among these: a BOQ that disagrees with the drawings, a specification that disagrees with the BOQ, or a scheme that the authorities later change. The 20 checks below close those gaps while correction still costs only drawing time.

Why review the design before the tender, not after the award?

After award, every correction becomes a variation: priced by the contractor, argued over, and often attached to a delay claim. Before tender, the same correction costs a designer's hour. The Department of Expenditure's Manual for Procurement of Works (Second Edition, 2025) says the same for item-rate contracts: specifications, design, drawings and contract conditions have to be critically appraised before procurement starts, to minimise internal inconsistencies, variations and claims.

The manual also explains how quantity errors turn into money. Quantities in a BOQ are best estimates and payment follows measured quantities. Major errors in items or quantities can lead to large variations, and bidders who spot an error can build a quotation that ranks lowest on the faulty quantities and gain a windfall when the quantities are corrected. That is why the manual notes that procuring entities have special procedures for quantity variations above 10 percent. Our notes on who pays for BOQ quantity mismatches and on a BOQ that cannot be gamed show the commercial side.

The 20 checks

Which checks catch the most expensive errors?

Checks 13, 15 and 16 are the ones that cannot be fixed cheaply later. An incomplete load schedule makes the transformer, DG and cable sizes wrong at the root. A fire scheme that does not match the occupancy changes pumps, tanks and pipe sizes. A single-line diagram that disagrees with the DISCOM sanction stalls energisation. All three also ripple into the approvals sequence, which our guide to the drawing set that approvals need explains.

The next group is quantity and scope: checks 1 to 5 and 14. The manual treats quantity variation as a recognised pressure point. It describes reasonable variations in BOQ quantities, typically plus or minus 10 to 15 percent, and says that larger variations usually require sanction and either a revised rate or treatment as a new item. Whether you use those bands or others, state them in the tender before bidders price.

How should the review be run?

1. Freeze a drawing set. Review one issue, with a revision register. Reviewing a moving set produces comments on drawings that no longer exist.
2. Use someone who did not draw it. The designer will read what was meant. A second engineer reads what is on the sheet. Our article on design peer review describes how an independent check works.
3. Write findings against the checks. Number them, assign an owner and a closing date, and close them in the drawings, not by email.
4. Hold the pre-bid meeting. For turnkey and special contracts the manual calls for a pre-bid conference, with minutes and answers published to all bidders. Use it to correct anything the review found late.
5. Re-issue once. Issue the tender set with a record of what changed since the review.

The manual cautions against over-specification in EPC tenders, because it adds cost. A review is also the moment to remove specification items that no calculation supports. Use the MEPF cost calculator to sanity-check the overall budget before the tender goes out.

How Secured Engineers helps

Our MEP design review is done by the same in-house engineers who draw for approvals. They check the electrical, HVAC, fire fighting and plumbing sets against the 20 points above and against the drawings that Fire NOC, Electrical Inspector and DISCOM filings will need, all handled in-house. MEPF and solar can sit under one contract if you later want us to price the execution, and an independent review stands alone if you do not. We work from Noida (Delhi NCR) and Ludhiana, with 535+ projects across 18+ states and 89.77% repeat clients. We review drawings and BOQs; we do not sell audits.

To book a review before you release a tender, send the drawing set and BOQ to our design review and approvals team, message us on WhatsApp, call +91 70099 85817, or ask for a free proposal.