The work
What flat roofing actually involves
Single ply or built up, and why the falls matter more than either
Flat roofs are not flat. They are laid to a shallow fall so water leaves, and the coverings in normal use are single-ply membranes, which come as large sheets welded at the seams, or built-up systems of layered felt and bitumen.
Whichever covering goes on, the thing that decides how long it lasts is whether the water gets off it. Standing water finds every weakness in a seam, adds weight, and in cold climates freezes and works joints apart.
If there are dark rings or silt patches on the existing roof two days after rain, the falls or the drains are not doing their job, and re-covering without fixing that buys you a newer roof with the same problem.
The seams
A flat roof fails at its joints, so count them
The field of a membrane rarely fails. The failures are at seams, at upstands where the roof meets a wall, around drains, and at any penetration through the covering.
That makes the layout worth asking about. Fewer, wider sheets mean fewer seams; a roof detailed to run the seams across the fall rather than along it puts every joint in the path of the water.
It also makes the upstand height worth checking. Where the covering turns up against a wall, it needs enough height above the finished surface to keep driven rain and ponding out, and cutting that short is invisible until it is not.
Failure points
Two things that go wrong
Covering over a wet build-up
“Has anyone cut a core to check whether the existing build-up is dry?”
Laying a new membrane over an old one that has taken on water seals the moisture in, where it drives blisters and rots the deck from above. On anything that has leaked, the question is whether the existing layers are dry, and the honest answer usually requires a core sample.
Drains and outlets left as they were
“Are the outlets and drains being replaced as part of this?”
Re-covering a roof and reusing tired outlets puts the newest part of the system against its oldest component, right at the one place all the water goes. Outlets are cheap relative to the roof and they are where re-covered flat roofs most often leak first.
Before you book flat roofing
How we rank →Six checks, in the order they save you the most. None of them takes longer than a phone call, and the first one is the reason two quotes for the same job can be a thousand apart.
Where we cover it
Roofing shortlists by city
Every shortlist →A company offering flat roofing appears in the published list for its own market. Each one names the editor who built it and the date they last checked it.
On the lists
Companies that list flat roofing
Drawn from the profiles where this service is recorded, not from what a company advertises.
TopCraft Roofing
Dallas, TX
Read first
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Common questions about flat roofing
Who handles flat roofing?
Flat roofing is handled by roofing companies. Not every company in the trade takes this work on, so each ranking lists the services a company genuinely performs rather than everything it advertises.
What should I ask before booking flat roofing?
Ask what the quote includes and excludes, who is doing the work, whether a permit is needed and who is pulling it, and what the workmanship warranty covers. Get the answers in writing before anyone starts.
How do I compare quotes for this?
Put them on one sheet line by line. Differences in price almost always turn out to be differences in scope, material grade or warranty length rather than margin.
Is flat roofing priced separately from the rest of the job?
Usually it is a line inside a larger quote rather than its own invoice, which is exactly why the exclusions matter. Ask for it itemised so you can compare that line between companies instead of comparing two totals.
For roofing
Do you offer flat roofing?
Claim your profile so the services you actually perform are the ones recorded here, alongside your licence, hours and coverage. Neither claiming nor advertising buys a ranked position.