There is no price on this page. Not a range, not a rate, not a typical figure for a typical leak. A leak repair is the least predictable purchase on a commercial building, and a number printed here would be wrong for almost every reader who found it.
What can be set out honestly is where the money goes, which variables move it and by how much, and which of them you still have some control over. That is more useful than a figure anyway, because it lets you read the quote you were sent.
No figure here, and the reason
Two buildings can call about the same symptom, a stain on a ceiling tile after heavy rain, and buy completely different jobs. On one, the crew walks up a stair, finds an open lap thirty paces upslope of the stain, welds it and leaves. On the other, the entry point takes half a day to find, the insulation around it is wet across an area nobody can see from below, and the repair becomes a cut out and replace job behind a permit.
Both are leak repairs. Both were quoted honestly. A published average sits between them and describes neither, and the reader whose roof is the second kind walks into the conversation believing they are being overcharged.
Where the money goes on a leak repair
A leak repair invoice usually has more labor on it than materials, and it breaks into five parts.
Attendance is getting a crew, a vehicle and a safe route onto the roof. Tracing is the search for the entry point. Opening up is the cutting and lifting needed to see what is under the membrane. The repair is the part most people picture, and it is often the shortest. Recording is the photographs, the cause written down and the finding placed on a plan.
The proportions move enormously between jobs. On a straightforward leak the repair might be the biggest line. On a stubborn one the search can be most of the invoice, and the physical repair is half an hour of work on a detail the size of a dinner plate.
It is worth asking which of the five the quote in front of you actually covers. A price that includes attendance and the repair, but assumes the entry point is already known, is a fair price when somebody has found it and a fiction when nobody has. A quote with no line at all for opening up is telling you that the plan is to seal the surface and hope.
Why the search is priced as work
Tracing is the part owners query most, because nothing appears to happen while it is going on. It is also the part that decides whether the repair holds.
Water enters a roof at one place, runs along the top of the deck and drops through the first opening it finds, so the stain marks the lowest hole in the deck rather than the fault. Finding the fault means working against the fall, checking every detail upslope, and testing the suspects rather than guessing at them. Our guide to roof leaks sets out the methods and what each one is good for.
The methods cost differently. A visual search uphill is the cheapest and finds most leaks on most roofs. A moisture meter adds a little and maps how far the water has gone. An infrared survey costs more and earns it on large roofs. A controlled water test is slow by design, because it is done one detail at a time with somebody watching inside. All of them are cheaper than three repairs in the wrong place, which is the alternative and the usual history of a roof that has leaked for years.
What an emergency call adds
Calling at night costs more than calling on Tuesday morning, and part of that premium is unavoidable. Out of hours rates, a crew redirected from other work, lighting, and the slower pace of anything done in wind and rain all sit on the first invoice.
The larger cost is structural to the situation rather than to the rates. Almost nothing bonds to a wet cold roof, so the night work is temporary by design and the permanent repair is a second visit. You pay two attendances for one leak. Against that, the interior damage you prevent is usually worth more than the premium, which is why the call is still the right one when water is coming in. What you should not pay for is temporary work described as a repair. Our page on the first visit covers what that night should and should not include.
The cost of a guess
The most expensive leak repairs are rarely complicated. They are the ones that were guessed at three times.
The pattern is familiar. A contractor attends, seals the membrane above the stain, invoices and leaves. The next heavy rain brings the same drip. Somebody else attends, seals a slightly larger area, invoices and leaves. Each visit carries its own attendance cost, the wet area underneath keeps growing between visits, and by the time anyone traces the leak properly the repair has become insulation replacement.
Add the visits together and the search that nobody wanted to pay for was the cheapest line available. This is the single best argument for insisting that a quote names the entry point and states how it was established.
What the leak costs besides the roof
The roof invoice is not the whole number. Wet insulation stops insulating, so heating and cooling costs drift upward quietly. Ceilings, finishes and stock absorb water. Persistent damp in a closed void brings its own remediation cost. A tenant with a bucket in an aisle is a commercial conversation as well as a building one.
None of that appears on a roofing quote, and all of it grows while the leak runs. It is the real reason that reporting a leak early is worth more than negotiating hard on the repair.
Who pays, and what decides it
Three documents usually decide who carries the cost: the insurance policy, the roof warranty and, in a let building, the lease. The cause of the leak and the quality of the paperwork decide how each of them lands, which is why photographs and a written cause matter beyond the roof.
We do not decide coverage and neither does any contractor. What we can do is record what was found and why it failed, in a form an insurer, a warranty provider or a tenant can read. A repair invoice that says only that a leak was attended and repaired is worth nothing in any of those three conversations. Keep the photographs with the invoice and the warranty paperwork, in one place, for every leak on every roof you hold.
Getting a number you can rely on
Ask for the quote to separate attendance, tracing, opening up, the repair itself, any insulation replacement and disposal. Ask what it assumes about the insulation, and what the rate will be if more board turns out to be wet. Ask whether the price covers a permanent repair or a hold. Ask what documentation comes back.
Then ask the question that filters most of it: where did the water enter, and how do you know. Everything else on the quote depends on the answer, and a price built on a guess about that will not survive the first rain after the work. For the wider picture on repair pricing, read what drives a roof repair cost.
Common questions
Why is finding the leak charged separately from fixing it?
Because they are different work with different lengths, and putting them in one line hides which of them you are actually paying for.
- Tracing is labor with an uncertain duration and no materials
- The repair is materials and labor with a scope you can see
- A single figure makes it impossible to tell whether the search was done
- Separating them lets you stop after the search if the answer changes the plan
There is a second reason to want the split. If the search finds something other than a roof defect, condensation on cold pipework or a failed condensate tray, the work stops there and you have paid only for the diagnosis. That happens more often than owners expect.
Does it cost more because the leak has been running a while?
Yes, usually by a wide margin, and this is the largest lever an owner controls. A leak reported the week it starts is often a surface repair. The same leak after a season rarely is.
- Water spreads sideways through the joints between insulation boards
- Wet board does not dry under a membrane, so it has to be cut out
- Cutting out brings materials, labor and disposal into the price
- Long running leaks reach the deck, which can turn a roof job into a structural one
The wet area grows in every direction while the leak runs, and none of that growth is visible from the ceiling below. That is why a stain somebody has been walking past for months is the expensive call, and the one dripping since Tuesday usually is not.
Why did two contractors quote very different work for the same leak?
Almost always because one priced the cause and the other priced the symptom. The numbers are different because the jobs are different.
- Sealing above the ceiling stain is quick, cheap and usually wrong
- Tracing upslope, opening the detail and replacing wet board is none of those
- One quote may assume the insulation is dry without anybody checking
- One may include making the area good afterwards and the other may not
Ask both of them the same question: where did the water enter, and how did you establish it. A contractor who traced the leak can answer without hesitation. One who cannot answer has priced a patch above a stain, which is the repair that comes back in the next heavy rain.
Does a warranty mean the leak repair costs us nothing?
Rarely nothing, and sometimes a great deal less. What a warranty covers, and whether it is still alive, decides the answer rather than the leak itself.
- Material warranties cover the membrane, not usually the damage underneath it
- Most require prompt reporting, and a leak left running can end cover
- Work must normally be done by an approved contractor with approved materials
- Damage from storms, traffic or another trade is usually excluded
Send us the warranty paperwork before anyone goes on the roof. If we are not approved under it we will say so, because a repair by the wrong contractor can end cover with years still to run, which costs far more than the repair saved.
Is it worth paying for a moisture or infrared survey to find one leak?
For one straightforward leak on a small roof, usually not. On a large or complicated roof, or where the same area has been repaired more than once, it often pays for itself in a single visit.
- A survey maps the wet area as well as pointing at the entry point
- Knowing the extent is what lets a repair be priced rather than estimated
- It replaces repeat visits, which are the most expensive way to search
- It is worth far more before a coating or a restoration than after one
The test is what the result will change. If it will tell you how much insulation has to come out, or whether you are buying a repair or a section replacement, it is cheap. If the roof is small and the detail above the stain is obviously open, it is not.