Roofing
Flat roofs
for a rowhome city.
Philadelphia is a flat-roof town. Whole blocks of rows, twins and trinities are covered by a low-slope deck with a parapet around it, and every one of them lives or dies on its laps, its terminations and whether the water can actually get off it.
Scope
What a flat roof replacement includes
A granulated cap sheet is the replacement. Black & silver and silicone are coatings — maintenance, not a new roof — and we will tell you honestly which of the three your roof actually wants.
- Tear-off of the old roof and any wet, saturated insulation underneath
- Deck inspected and re-sheeted where it has gone soft
- New insulation board or recovery board, fastened to spec
- Self-adhered or torch-applied base sheet, then a granulated cap sheet over it
- Laps rolled properly — the lap is the whole roof
- Parapet walls and curbs flashed up and terminated with a metal bar and sealant
- Drains, scuppers and downspout connections re-worked so water actually leaves
- Ponding areas tapered rather than ignored
The difference
Where flat roofs actually fail
The laps
A rolled roof is only as good as the joints between the sheets. Cold, dirty or half-rolled laps open up in a few seasons. Ours get cleaned, properly bonded and rolled the whole way out — and we keep laps out of the low spots entirely.
The terminations
Where the roof turns up a parapet or a chimney and stops. That top edge needs a termination bar and sealant, not a nail and a prayer. It is the second most common flat-roof leak we get called to.
The water that never leaves
A flat roof is never truly flat — it is pitched to a drain or a scupper. Block the drain, crush the insulation or let a low spot form and you get ponding, which finds every weakness and kills a roof early.
Before & after
Failed coating,
new membrane.
The coating on the left had gone chalky and lost its grip — which on a flat roof means water is already sitting on the seams. New membrane, wrapped around the cone dormer and run out to every parapet.
Before you decide
Types of Roofing
The four roofing systems we install and maintain — one for pitched roofs, three for the flat roofs on this city's row homes. What each one is, what it costs relative to the rest, and how long it actually lasts.
Straight answers
Flat Roofing & Coatings — FAQ
Also from us
The rest of the outside
of your house.
Related reading
Worth reading
before you decide.
Free estimate
Free inspection. Written estimate. No pressure.
Tell us what you are looking at and we will come and look at it — and we will tell you honestly what it needs, including the times the answer is nothing yet.