Commercial roofing in Lake Butler, FL

Florida's current code sets the minimum design slope for new low-slope roofs at one-fourth unit in 12, which is 2 percent. Built-up, modified bitumen, single-ply and liquid-applied systems all carry that floor. A roof that barely meets it can still hold water, so ask where the water will go.

Water covers 35.7 percent of Lake Butler's total area, against 10.0 percent for Orange County as a whole. The code requires secondary overflow drains or scuppers where a parapet could trap water, and storm drainage is sized on a 100-year hourly rainfall rate. Ask each bidder how their design handles that load on your roof.

• Confirm the slope on the drawings, not only in the proposal.
• Ask how ponding water will be checked and corrected.
• Require edge metal tested to the wind standard named in the code.

Compare bids by scope, not total. Each one should name the membrane type, the material standard it meets, and the wind and edge testing. Single-ply membranes here are checked against ASTM standards such as D6878 for TPO, and proposals that skip the standard are harder to compare.

Florida law requires a general contractor to subcontract roofing unless the contractor holds a roofing certification or registration. Ask to see that license for the entity doing the work, and check it with the state before you sign.