Commercial roofing in Apollo Beach, FL

Apollo Beach was planned from the 1950s around canals, and water covers 11.7 percent of the place's area. Much of the original land was low mangrove ground. Flat commercial roofs here must shed water fast, because Tampa's normal rainfall is 49.48 inches a year, with about 61 percent falling June through September.

A new low-slope roof must have a slope of at least one-fourth unit in 12, equal to 2 percent. That applies to modified bitumen, built-up, single-ply and foam. Parapets that might hold back water trigger a code requirement for secondary overflow drains or scuppers. Each bidder should be able to point out the overflow location to you.

A recover over old roofing is barred where the existing roof is water soaked or already has two or more coverings. In those cases the bid should be a full tear-off to the deck.

• Ask which single-ply standard applies. TPO sheet follows ASTM D6878 and EPDM follows ASTM D4637.
• Ask how metal edges will be tested. The code points to ANSI/SPRI ES-1 tests for edge systems on low-slope roofs.
• Ask whether rooftop equipment is being replaced or moved. Existing equipment only has to meet current code when it is replaced or moved.
• Check that the roofing contractor's license is current on the state lookup before you sign.

Also watch the 25 percent rule. If more than 25 percent of a roof section is repaired or replaced in 12 months, the whole section must be brought up to code. The exception applies only to a roof built or replaced under the 2007 code or later. A bid that ignores this rule may be priced for a repair the permit office will not accept.