Repair it, or replace it
Roofing companies make far more money on replacements than on repairs, which is exactly why a homeowner should know the three questions that settle it before anybody arrives.
- Sheet
- A03
- Subject
- Repair versus replacement
- For
- A homeowner with a leak or a worry
- Trade
- Roof repair, roof replacement
Question one: is the failure a detail or the field?
Almost every roof that leaks is leaking at a detail rather than through the middle of a slope. A pipe boot has split. Step flashing at a dormer has rusted or was reused. The kickout at the bottom of a roof to wall junction was never there. A valley has debris packed in it and the water backed up under the course. A ridge vent was fastened badly and is taking wind driven rain. Every one of those is a repair, and on a roof with life left in it a repair is the correct and honest answer.
The field is a different matter. When the surface itself has gone, the symptoms are general rather than local: granules filling the gutters after every rain, shingle corners curling or cupping across whole planes, mats that crack rather than flex when you lift a tab, bald patches where the asphalt is showing through. That is not a leak with a location. That is a roof at the end of its service life, and patching it is renting time at a bad rate.
A quick test
On a warm day, gently lift the bottom edge of a shingle at the middle of a slope. A roof with life in it will flex. A finished roof will crack, and the crack will tell you more than any inspection report.
Question two: how far into its life is it?
Nobody can give you a fixed number of years for a roof in this climate, and this page is not going to print one. What can be said honestly is that an asphalt roof in the St. Louis metro is working against a specific set of stresses: a long hot humid summer that keeps attic temperatures high, a freeze and thaw cycle that works fasteners loose over and over each winter, and a spring storm season that arrives with wind and hail. A roof that is well ventilated ages far more slowly than an identical roof that is not, which is why sheet A08 exists.
The practical version is this. If the roof is early in its life and the failure is local, repair it. If the roof is late in its life and the failure is local, the arithmetic gets awkward, because a repair now means paying for access and setup twice. If the roof is late in its life and the failure is general, replace it, and be suspicious of anybody who offers to patch it cheaply, because they are selling you a callback rather than a solution.
Question three: will the repair match, and does that matter to you?
This is the one that gets people, and it is the one where a great deal of nonsense circulates in this market. A spot repair on a roof that is ten or fifteen years old will not match. Colour blends change, granules weather, and the manufacturer may not even make the blend any more. A patch of new shingle in the middle of a weathered plane is visible from the street and will stay visible.
Missouri has no matching statute and no matching regulation for roofs. The citation people repeat at each other online governs automobile body parts, not roofs, and it does not apply here. Missouri has case law on the question and nothing else: Alessi v. Mid-Century Insurance, 464 S.W.3d 529 (Mo. App. E.D. 2015). Whether a mismatched repair is acceptable turns on the wording of your own policy, which is a matter between you and your insurer, and any roofer who tells you the law requires a full replacement for appearance reasons is telling you something that is not so.
So the honest framing is a preference question, not a legal one. If the repair is on a rear slope nobody sees, a mismatch is a non issue and a repair is good value. If it is on the street elevation of a house you intend to sell in two years, it is worth weighing. Either way, the person telling you which it is should be the person who is not getting paid more for one answer than the other, which is a real limitation of asking a roofer, and it is why this page tells you the test instead of telling you the verdict.
When Keys will say repair
- One failed penetrationA split boot, a rusted collar, a bad seal at a flue. Cheap, quick, and completely fixable on a sound roof.
- Flashing at a wall or chimneyStep flashing renewed properly, counter flashing cut in. This is skilled work and it is a repair, not a replacement trigger.
- Storm damage confined to one slopeWind lifts a section of one plane and leaves the rest alone. It happens constantly and it is a repair.
- An isolated soft spot in the deckBoards or a sheet replaced, the surrounding shingle re-laid. Worth doing well before it spreads.
When Keys will say replace
- Shingles that crack when liftedThe mat has gone brittle. Anything done to it will damage what is next to it.
- Granule loss across whole planesOnce the asphalt is exposed, ultraviolet does the rest quickly and there is no repair for it.
- Two or more layers already upA layover on a layover is not an option, and the deck under it needs looking at anyway.
- Decking failing generallyIf the deck is soft in several places, replacing shingle over it is putting new material on a bad foundation.