Weather proofing material is the topmost or outermost layer of the roof that is exposed to the weather. Many different kinds of materials have been used as weather proofing material including:
- Shingles & Faux Shingles - Slate. Long life, High cost ;Ceramic. Long life, High cost ;Metal. Long life. High cost, should be on roofs of 6/12 pitch or greater. ;Cement (usually reinforced with fibres of some sort) ;Asphalt shingle (bitumen embedded in an organic or fiberglass mat, usually covered with colored, man-made ceramic grit) Cost effective. Various life span expectancies.; Cedar. Long life. However, young growth cedar has a short life expectancy. High cost. Should be allowed to breathe.; Asbestos shingles. very long lifespan, Fireproof, low cost, Rarely used anymore as dust from installation is thought to be carcinogenic.
- Membrane - Thermoset (e.g. EPDM synthetic rubber). Synthetic rubber sheets adhered together with contact adhesive or tape. Primary application is big box store with large open areas and little vertical protrusions. Relies heavily on the skill of the applicator. Detail critical.;Thermoplastic (e.g. PVC, TPO, CSPE). Plastic sheets welded together with hot air. Can be rewelded with the exception of CSPE. Lends itself well to both big box and small roof application because of its hot air weldability. Relies heavily on the skill of the applicator. Detail critical. ;Modified bitumen - heat welded, asphalt adhered or installed with adhesive. Asphalt is mixed with polymers such as APP or SBS, then applied to fiberglass and/or polyester mat, seams sealed by locally melting the asphalt with heat, hot mopping of asphalt, or adhesive. Lends itself well to all applications. Requires some training.; Built-Up Roof - Multiple plies of asphalt saturated organic felt or coated fiberglass felts. Plies of
- Metal- Corrugated metal with exposed fasteners; Standing-seam metal with concealed fasteners; Flat-seam metal with soldered seams
- Fabric - Dacron/polyester; Teflon embedded in fibreglass
- Straw, or reed thatch