Skip to content
Local Commercial Roofing

Hiring and Proposals

How to read a commercial roofing proposal (line by line)

A facility manager checklist for commercial roofing proposals: scope, insulation spec, warranty tier, exclusions, and the questions that expose a thin bid.

Written and reviewed by James Turner

Roofing contractor with 20+ years in roofing and insurance restoration

Published July 3, 2026 · 1 min read

This is an early version. The full article, with complete numbers and sources, lands in an upcoming update.

What should you check first in any commercial roofing proposal?

The scope, before the price. A commercial proposal is a scope document wearing a price tag: what comes off the roof, what goes back, at what thickness, attached how, and warranted by whom. Two bids $80,000 apart are almost never the same roof at different margins; they are different roofs. Read the scope until the difference is visible, then talk numbers.

This guide is an early version; the complete line-by-line walkthrough with a printable checklist is in production.

Which lines hide the money?

Four places, reliably: the insulation spec (thickness, R-value, and whether existing insulation is reused), the tear-off definition (to the deck, or just the membrane), the warranty tier (material-only versus NDL system warranty), and the exclusion list (deck repair unit pricing, plumbing, electrical, and code upgrades). The system sheets show what a complete assembly includes, which makes missing layers easy to spot.

How do you compare bids fairly?

Force identical scope and re-quote. Pick the spec you actually want, send it to every bidder, and require deck repair unit prices in writing. Then check the numbers against the flat roof cost estimator range for your size and system: bids far below the bottom left something out, and you now know where to look. If you are not sure replacement is even the right project, run the repair vs restore vs replace tree before signing anything.

Finally, ask every bidder one question and write down the answer: who is physically on my roof, your crew or a subcontractor? Neither answer disqualifies anyone, but a contractor who hedges on it will hedge on the punch list too, and the warranty conversation gets harder after the checks clear.

Frequently asked questions

Why do commercial roofing bids vary so much for the same roof?
Because they rarely price the same scope. Insulation thickness, tear-off depth, warranty tier, and the exclusion list move a bid by 30 percent or more before workmanship even enters the picture. Normalize the scope and the spread usually collapses.
What is the single most important line in a proposal?
The insulation spec. It is the easiest place to hide cost: reusing existing insulation the code requires upgrading, or quoting R-20 where the jurisdiction requires R-30, changes the price and the legality of the job at once.
What does NDL mean in a roofing warranty?
No Dollar Limit: the manufacturer covers the full repair cost of covered defects for the term, rather than a prorated or capped amount. NDL warranties require manufacturer inspections during installation, which quietly buys you quality control.