Commercial roofing in Land O' Lakes, FL

New low-slope roofs need a minimum design slope of one-fourth unit in 12, or 2 percent, for built-up, modified bitumen, single-ply and spray foam systems. Water that stands longer than 48 hours after rain means the drainage was not designed to the code's own definition of positive drainage.

Where drains are required, a roof with a raised perimeter also needs secondary overflow drains or scuppers. Pasco County property saw more than 10 inches of rain in parts of the county during Hurricane Hermine in 2016, so overflow capacity is a real question for your roof, not a formality.

The 25% rule limits repair, replacement or recovery to 25 percent of a roof section in any 12-month period. Past that, the whole section must be redone. A section last built or redone under the 2007 code or a later edition is treated differently, and the new work alone must meet current code.

Ask each bidder to name the membrane standard. TPO should meet ASTM D6878, EPDM ASTM D4637, and PVC sheet ASTM D4434. Florida's code places TPO and PVC inside the single-ply section, so bids should cite the same numbers.

• Roofing product named with its Florida statewide approval number, searchable on the Florida Building Commission site
• A tear-off to the deck if the old roof is water soaked or already has two or more coverings
• Metal edge systems tested to ANSI/SPRI ES-1 or RAS 111
• Notice of Commencement recorded and posted before the first inspection, as the permit card warns

Your tenants and unit owners live with the result of a bad choice. A 2018 EF1 tornado near Land O' Lakes condemned two homes over roof damage, and Hurricane Irma put a 48 knot gust at the Land O' Lakes weather station. Ask how the bidder's edge and deck attachment details answer wind like that.