Roof leak repair cost

Water travels; find the entry first

The stain on the ceiling is almost never under the hole. Water enters at a penetration or a lap, runs down the underside of the deck until it meets a rafter, tracks along that rafter until something interrupts it, and drops. Ten feet of horizontal travel is ordinary. That is why a repair quote that names an entry point is worth more than one that names a price.

Trace it from inside with a torch on a wet day: follow the wet line uphill to the highest point of staining on the sheathing, then measure that point from the ridge and from the nearest gable so you can find it from above. A paid diagnostic inspection runs $307 to $571 and is usually credited against the work.

The five sources, and what each costs

Add deck repair at $2–$8 a square foot wherever the sheathing has been wet long enough to soften — which, on a leak that has run for a season, is usual rather than exceptional.

How bad is it, really

What a tarp buys you

An emergency tarp runs $300 to $1,000 and buys weeks, not months. It is worth it when the alternative is water in the house, and it is worth nothing at all if it is fastened through sound shingles — every fastener is a new hole. After a storm, tarp and photograph before you clean anything up: the photographs are the claim. The claim guide covers what happens next, and the repair cost guide has the repair-or-replace arithmetic.