TPO and modified bitumen flat roofs installed in Jacksonville

Almost every flat roof failure traces back to water that stayed too long: ponding at a low spot, a drain set too high, a scupper that backs up in a downpour. The membrane choice matters, but the slope under it matters more. On a replacement, we map where water sits today and correct it with tapered insulation or crickets before the new membrane goes down.

Then the details. Seams, curb flashings, parapet caps and edge metal are where membranes leak, so they get the most attention and are photographed before anything covers them.

TPO is a single-ply white membrane, heat-welded at the seams into one continuous sheet. Done right, the welds are stronger than the sheet itself, and the white surface reflects sun, which keeps rooftop temperatures down in a Jacksonville summer. It is fastened mechanically or fully adhered over insulation, and flashed with the same material welded to curbs and walls.

We probe every weld after it cools, because a cold weld looks the same as a good one until it opens. We install Carlisle and comparable TPO systems.

Tapered insulation boards are cut at a slight pitch so the finished roof surface slopes toward drains even when the deck below is dead flat. Crickets, small tapered wedges, divert water around curbs and toward scuppers. Designed as a system, they eliminate the low spots where ponding starts and add insulation value at the same time.

Where a roof has too few drains, adding one is often cheaper over the roof's life than fighting ponding. We lay out the taper from a survey of where water sits after rain, not from a generic plan.

Typical market range for flat roof drain or scupper retrofit: $300 to $450 per drain (source). A planning figure, not a quote.