What a roof replacement costs around St. Louis
Two bids on one house can differ by thousands, and greed is rarely the explanation. They include different work. Around St. Louis the gap tends to sit in the details this housing stock demands: what comes off, what the deck needs, how the roof meets the brick, and what happens at the attic.
The lines that move the number
Tear-off first: code allows two layers at most, and a lot of the region’s postwar housing was re-covered once in its history, so this replacement often strips to the deck — more labour, more disposal. Decking is the wildcard, priced per sheet by anyone doing it honestly; boards that have been through two tear-offs have taken a lot of nails, and boards under a starved attic may have spent decades damp. Geometry does the rest: hips, valleys, dormers and wall junctions add labour that square footage alone never predicts.
Then the lines this region makes non-negotiable. Flashing replaced rather than reused — including counterflashing reset into the mortar wherever the roof meets brick, slow work that thin bids skip. Valley construction named: open metal sheds the canopy litter and the winter refreeze; woven shingle traps both. Ventilation, intake and exhaust in balance, because the new covering’s lifespan is decided in the attic every July. And on pre-war houses, the two specialty items: built-in box gutters (reline or convert — either way it must be in the quote) and any low-slope section, which needs membrane, not shingles.
Reading the spread
When bids land far apart, line them up against that list and the mystery usually dissolves: the low bid reuses flashing, guesses at decking, and never mentions the gutter detail or the attic. It is not a better price for the same roof — it is a price for less roof. The useful comparison is never bottom line against bottom line, but line against line.
Two habits make the comparison honest. Ask every bidder the same three questions — layers, decking price per sheet, ventilation plan — so the answers are comparable. And get the permit named: who files it and in which municipality, because in this metro the answer changes from one street to the next, and a bidder vague about the permit is telling you something.
Quick answers
- Why are two quotes for the same house thousands apart?
- They price different work. The spread usually hides in tear-off layers, decking allowances, whether flashing and counterflashing are replaced or reused, ventilation, and — on older St. Louis homes — box gutters and low-slope sections. Compare line by line, not total by total.
- What is the most commonly missing line on a thin quote?
- Attic ventilation. It is inexpensive, it is what protects the new covering from the St. Louis summer, and shingle warranties can hinge on it — which is exactly why leaving it out makes a bid look cheaper than it is.
Every roof is its own arithmetic — layers, deck condition, geometry, access. Use this page to read quotes, not to predict your number without one.