ROOFING MATERIALS

By Aysha Shad Ali Sharukh Shamz

There are enormous variety of roofing materials available based on price , durability , appearance and slope .

For pitched roof1. Asphalt shingles2. Metal 3. Wood 4. Slate 5. tile For low slope and flat

roof1. Roll roofing 2. Membrane3. Built up

Square materials which are necessary to cover 100 sq.ft. of roof surface.

Exposure-number of inches (of) shingles left exposed above bottom edge

coverage-number of layers of material that are applied

Asphalt shingles Most widely used. Several different types. Lifespan of 15-25 years

Steel shingles Made out of aluminum or other steel types. Typically carry lifetime warranty

Cedar shingles Cedar wood shims. Cedar oils naturally repel water and

insects. Last 40-50 years

Asbestos shingles Very long lifespan Fireproof and low cost Rarely used now a days because of

health concern.

Clay roof One of the oldest roof coverings. Requires little maintenance, and is fire, mould and insect resistant. Fragile, and expensive. Used commonly in warmer climates Applied with mortar or using nails Traditionally applied over purlins, nailed to sheathing today

Slate Shingles Actual slivers of rock used as shingles. Long lifespan. Similar to clay. Heavy and requires a strong roof Expensive Roof framing must be reinforced for the weight Slate should not be walked on if old Can be repaired with clip normally fastened

with copper nails in pre drilled holes

Metal roofing Recent improvement in paint quality

and life have brought more painted steel roofs into the residential market.

Cost competitive with asphalt shingles , used commonly for agricultural structures

Attached with gaskated nails or more commonly with gaskated screw.

Roll roofing Traditionally used for low-slope residential work Available in single and double coverage Very expensive , but considered

unattractive Applied with nails and tar , tar typically

leaked out at edges.

Membrane roofing “rubber” roofing and other material come in

sheets or rolls , are glued or ballasted to the roof Materials are relatively expensive, but roof is long lasting and stays flexible. thermoset membrane thermoplastic

Hips-hip roof are shingled up to the hip cap, and the capped

Valleys-are a collection source for water, and a common point for leaks. Valley can be handled as opened or closed. Closed valley can be cut or woven.

open valleys are used with either mineral surface roll roofing or aluminum flashing in the valley. Width of watercourse increase down the valley. advantage is unobstructed watercourse and disadvantage is appearence

Closed valley-closed valleyare either woven or cut. woven valley require shingles on each roof to be laid at the same time. provide double thickness the full valley length. Require the same pitch on each roof.