Roof repair or replacement: the signals that decide

A roofer stands in your driveway and tells you the roof is done. Maybe it is. The problem is that you cannot check his work from the ground, and he knows it.

So do not argue about the conclusion. Ask which signals he saw, then go and look at them yourself. There are about six that genuinely decide it, and only one of them needs you to leave the ground — and that one is the attic, not the roof.

The signals that say replace

No single one of these is proof. A roof with one has a problem. A roof with three has run out of life.

• Age measured against the material's rated life, not against the calendar. Sun does the damage here rather than frost, so the south and west planes age years ahead of the north one on the same roof.
• Granules in the gutters. A handful in the first month is normal shedding. Years in, a bed of grit at the downspout and shingles that look bare and shiny means the asphalt has nothing left protecting it.
• Cupping or curling across whole planes, not just along one edge. Edges lift first; when the field is doing it too, the mat underneath has dried out.
• Leaks in more than one plane. One leak is a defect. Three, in different parts of the roof, is a material at the end of its service life.
• A sag or a dip in the ridge or the deck line, visible from across the street.
• Daylight through the sheathing, seen from inside the attic.

The last two end the argument. A sagging deck is framing or sheathing, not covering, and nothing you lay on top of it fixes it. A roof you can see daylight through has been letting water in for longer than anyone has been telling you.

Do the attic yourself. Take a flashlight up on a bright day, turn the light off, and look at the underside of the deck. Rings of dark staining, soft plywood, and pinholes of daylight are most of the story, and it takes ten minutes.

The signals that are usually a repair

• One leak that traces to one penetration — a vent, a skylight, a swamp cooler, a solar mount.
• Cracked, slipped or missing tiles over an otherwise sound field.
• Failed flashing where the roof meets something else: a chimney, a parapet, the wall of a second storey.
• A valley that was never built properly — too narrow, no metal, or shingles lapped the wrong way.
• A vent boot whose rubber collar has split. They split. That is what they do, on a schedule, and replacing one is an afternoon.

Flashing is the most common real cause of a leak that gets blamed on the roof surface. Water almost never comes through the middle of a healthy plane. It comes in where the roof stops being a roof — a chimney, a wall, a skylight, a pipe, a valley. Those are details, and details are fixable.

Water also travels. The stain on your ceiling is downhill from where the water got in, sometimes by several feet along a rafter. Anyone quoting a repair from inside the house, without going up and finding the entry point, is guessing.

What Los Angeles roofs are actually made of

Three families cover almost everything here, and they fail in completely different ways.

Composition shingle

The default. Cheapest to replace, easiest to repair, shortest life. It is sold with a warranty measured in decades and in this climate it rarely gets there: UV cooks the asphalt, the mat dries, the granules let go. When a roofer tells you one side is sun-baked and the other looks fine, that part is usually true.

Clay and concrete tile

This is the local trap. The tile is not the roof. The underlayment beneath it is the roof, and it has a fraction of the tile's life.

So a leaking tile roof usually does not need new tile. It needs the tile lifted and stacked, the old underlayment stripped, any bad sheathing replaced, new underlayment laid, and the same tile relaid with an allowance for breakage. That is a lift-and-relay, and it prices very differently from a tear-off where the covering goes in the bin.

If a bid says tear off and replace tile roof without saying whether your existing tile is being re-used, that is your first question. The answer moves the number more than anything else on the page.

Flat and low slope

Modified bitumen — torch-down — or a single-ply membrane. Rear additions, garages, mid-century flat roofs. These do not wear out across the field the way shingle does. They fail at seams, terminations, drains and parapet edges, and they fail where water sits after a storm and never leaves.

Plenty of LA houses are two roofs: a pitched original and a flat addition, different ages, different life left. Have them assessed separately. Replacing both because one is finished is a common and expensive mistake.

The second layer

Laying a new layer over the old one skips the tear-off. No stripping labour, no disposal, a faster job, a smaller number today. What it costs you is spread out.

• Nobody sees the deck. The one chance to find rotten sheathing is while the roof is open, and an overlay closes it back up unexamined.
• The new layer sits on the heat the old one holds, runs hotter, and ages faster for it.
• The eventual tear-off is two layers of disposal instead of one, at whatever disposal costs by then.
• The framing carries the dead weight of both. On tile that is not a rounding error.
• A permit inspection cares how many layers are already up there and what condition the deck is in. That is much of the point of pulling one.

An overlay is defensible on exactly one kind of roof: a single existing layer, a sound deck, no leak history, and an owner who knows what they are trading. On a roof with a leak nobody has located, it is a way to bury the evidence.

A real inspection versus a sales visit

Both take about the same amount of your afternoon. They are not the same event.

An inspection means someone got on the roof, or said plainly why they could not and used a ladder or a drone instead. Shingles or tiles were lifted. Someone went into the attic with a light and looked at the underside of the deck. Every penetration and every piece of flashing was looked at individually, and the gutters were checked for granules.

A sales visit means someone walked the perimeter, said the word granules, and produced a contract with a discount that expires today.

Insist on photographs, and insist on the right kind.

• Every defect twice: one frame close enough to see the problem, one wide enough to place it on your roof.
• The flashing at each penetration, individually.
• The deck from the attic side, including directly above whatever stain you called about.
• The valleys, full length.
• Anything they want replaced that you cannot see from the ground.

Photographs of somebody else's roof are common enough to check for. If a picture shows a different colour shingle, a different gutter profile, or weather you did not have, ask about it.

Insurance, briefly and honestly

Most roof failure in Los Angeles is age and sun. Storms are the exception here, not the rule, and that matters because policies are generally written to cover sudden accidental damage rather than wear.

A limb through the roof in a windstorm is worth a call to your carrier. A shingle roof in its third decade that has simply finished usually is not, and filing anyway mostly buys you a claim on your record. Read your own policy, because the terms vary more than people expect, and let an adjuster look before you sign anything with a roofer.

One warning. A contractor who volunteers to get insurance to pay for it, or offers to absorb your deductible, is proposing a paper trail with your name on it. Decline.

Timeline, permits, and rain

A straightforward single-storey shingle tear-off and replace is a matter of days, not weeks. Tile takes longer because every piece is handled twice. What drives the schedule is complexity rather than area — valleys, skylights, chimneys and dormers each add time that square footage does not predict.

Replacement is permitted work across the LA-area jurisdictions; your own city's building department will confirm the scope in one phone call. The permit is pulled under the licence the contract is written under, and inspections happen at set points in the job. A crew offering to skip it is telling you what the rest of their work looks like, and handing you a problem at resale when a buyer asks for permit history.

Then rain. Ask before the job starts, not during: how much roof do you open in a day, and what state is it in when you leave? The right answer is that they strip only what they can dry in the same day — underlayment down and sealed before the crew goes home — and that tarps are the contingency, not the plan. Los Angeles gives you long dry stretches. A competent crew still works as though it does not.

How to read a bid

Two roofing bids that differ wildly usually differ in scope, not in greed. Line them up on these and the gap explains itself.

1. Tear-off or overlay — and how many layers come off, with disposal named.
2. Deck repair: how replacement sheathing is priced, agreed as a rate before the roof is open rather than discovered on day two.
3. Underlayment: type and weight, stated. On a tile job this is the entire product you are buying.
4. Ventilation: what intake and exhaust exist now, and what is being added. A new roof over a badly ventilated attic ages the way the old one did.
5. Flashing: replaced or re-used, at every penetration, named specifically at the chimney and any wall. Re-use existing flashing on a bid is where the next leak comes from.
6. Drip edge and valleys — present, and how the valleys are built.
7. The warranty, in writing before you sign.
8. The payment schedule, and what the final payment is contingent on.

The warranty is the line people skim. Material and workmanship are two separate warranties, from two different parties, running for two different lengths — and the one that matters on a leak in year three is the workmanship one. Ask which is which, find out what voids each, and get the document rather than the adjective.

What a roof costs in Los Angeles

Fix one thing before you look at any number: roof area is not floor area. A roof is bigger than the house under it, because of pitch and because of overhang.

Start with the footprint — the ground-floor outline, so a two-storey house counts once, not twice. Add the eaves, which is more than people expect once you go all the way round. Then add for pitch: a gentle walkable slope adds only a few percent over the flat footprint, a moderate one around a fifth, a steep one closer to forty. A 1,500 sqft single-storey footprint with normal eaves and a moderate pitch usually lands near 2,000 sqft of roof.

Read the sizes below as roof area. 1,200 sqft is a small single-storey bungalow. 1,800 is a modest family house. 2,600 is a larger one, or a two-storey with an attached wing. 3,600 is a big or complicated roof carrying several planes.

What moves you off that baseline, roughly in order of weight: material, since tile and standing seam are multiples of shingle; then pitch; then a second or third storey; then complexity. In the other direction, repairing one plane is a fraction of replacing the roof, and the engine prices that as its own job.

These are instant estimates, not final contracts. The estimator asks the four questions that actually move a roofing number — scope, material, pitch, storeys — and prices your roof rather than an average one. Nobody has to come to the house for you to see it.

If you take one thing from this: do not decide in the driveway. Get the attic looked at, get the photographs, and get two bids written against the same scope. A roof that genuinely needs replacing will still need replacing next week and the signals will not have moved. A roof that needed a flashing detail will have been saved.