Roofing Materials, Systems, and Installation
Roofing Materials, Systems, and Installation
Roofing questions test whether you can match a system to slope, climate, and code. Slope is the first decision. Slope is rise over run; a 4:12 roof rises 4 inches per 12 inches horizontal. Low-slope roofs generally need membranes such as TPO, modified bitumen, or built-up roofing; steep-slope roofs use shingles, tile, metal, or synthetic systems. Installing a product below its listed minimum slope is a classic failure and exam trap.
Florida conditions add wind uplift, heat, UV, and rain. Fasteners must be the correct type, length, and spacing; corrosion resistance matters near the coast. Underlayment, secondary water barriers, drip edge, valley flashing, and penetration flashing must be installed in the correct sequence. Water must always shed over, not behind, materials. Ventilation affects attic heat and moisture.
Know common defects: exposed fasteners, insufficient laps, reversed laps, missing kick-out flashing, poor valley treatment, and fasteners driven through flashing.
Worked example: A plan shows a 3:12 slope. Do not specify standard asphalt shingles unless the manufacturer allows it and the underlayment meets code. Use a low-slope membrane or a system specifically approved for that slope. Rule of thumb: when slope and product data conflict, the product approval and Florida Building Code control.