Gutters in Martin County, FL

Florida's plumbing code sizes gutters by flow, in gallons per minute. A half-round 5-inch gutter at 1/8 inch per foot slope carries 74 gpm. A 6-inch carries 110 gpm. That is about 49 percent more capacity from one size up.

Downspouts are the next limit. A 3-inch round leader handles 92 gpm, and a 4-inch round handles 192 gpm. A long roof run feeding one small downspout backs up even when the gutter itself is large enough.

Roof pitch and walls add water. A steep 12-in-12 roof counts 1.30 times its plan area, and the code adds half the area of any wall that drains onto the roof. Ask your installer to show the numbers, not just a size.

The rainfall basis matters too. On one Florida example, the same 6-inch gutter serves over twice the roof area on the 1-hour basis as on the 5-minute burst. Insist the contractor says which basis was used.

Southern live oaks grow 60 to 80 feet tall with a spread of up to 120 feet, and their leaves are a known litter problem. A single oak can reach over a roof from the neighboring lot. Oaks and pines also drive Florida's pollen season, which peaks in March and April.

Needle drop on pine trees peaks in the stretch from September into November. A workable rhythm is cleaning after the spring oak drop, before June, and after the autumn needle peak. Do it more often under heavy canopy. NRCA says to inspect in fall and spring and clear gutters of dead leaves.

Hangers matter after storms. A hidden-hanger maker suggests 16-inch spacing and aluminum in coastal, storm-prone areas, against 24 inches standard. Nicole brought a 54-knot sustained wind at the House of Refuge in Martin County, and Isaias reached 42 knots at Stuart Beach.

Code requires metal or approved plastic gutters with lapped, soldered or caulked joints, fastened with corrosion-resistant fasteners. Granules collecting in gutters can also signal an aging shingle roof. About a third of homes here, 33.5 percent, predate 1980.