What you need to know about roofing materials

Roofs come in all shapes, sizes and materials. Here's the most common roofing materials available, and what they can do for you:

• Asphalt and asphalt-fibreglass shingles are made of roofing felt or fibreglass that's coated in asphalt and ceramic-coated mineral granules.
• The shingles  come in a wide range of colours.
• Asphalt is moderately priced and lasts 15 to 30 years.
• Repairs to damaged shingles are relatively easy to make.
• With proper framing, a second and third roof can be laid over the first one, saving you the expense of having the old roof torn off.

• Wood shingles and shakes are usually made of cedar, which has a natural resistance to decay.
• Shingles are smooth on both sides.
• Shakes are split on one side and have a rugged, hand-hewn look.
• Wood roofs are expensive and may raise your fire insurance rates.
• Shingles can last 20 years. Shakes up to 50 years.
• Regular fungicide and oil treatments should be applied to prevent mildew, especially in humid regions, and to minimize curling and cracking.

• Slate tiles are split and cut from natural stone.
• Because slate is heavy, it's most commonly installed on roofs with a steep pitch.
• Strong roof framing is needed.
• Good slate roofs can last from 50 to 200 years or more and are fireproof.
• Falling debris can crack or dislodge slates and slate nails can wear out, presenting a problem on old roofs.
• Replacing slates requires a professional, especially on a roof with a steep pitch.

• Clay tiles are made of kiln-fired ceramic clay. They come in half-cylinders, flat shingles and a variety of other styles.
• Some styles are interlocking, making it difficult to replace one tile.
• Clay can be expensive, but the shingles can last 50 to 100 years.
• Hire a roofer with clay-tile experience for repairs.
• Sometimes, it's possible to slip a piece of metal under a tile to repair a leak.
• Clay tile ridges, set in mortar, must be patched or reinstalled periodically.

• Metal is an increasingly popular roofing choice.
• Metal roofs are usually aluminum but stainless steel, copper and galvanized steel are also used.
• While moderately expensive, metal roofs can last up to 35 years
• Small holes and tears can be temporarily sealed using fibreglass mesh and roofing cement.

• Roll roofing is similar in composition to asphalt shingles but is laid in wide, overlapping strips.
• Roll roofing is easy to install and economical, but unattractive.
• It's normally used in places that aren't visible from the ground.
• Patch roll roofing as you would other flat roofing, or re-cover the area with new roofing.

• Built-up roofing is used for flat or nearly flat roofs.
• Traditionally, layers of felt are laminated with hot tar and topped with gravel, but rolls of modified bitumen are becoming more popular.
• Bitumen is cheaper to install than hot tar but both materials last from five to fifteen years.
• Because the surface is flat and water will not run off, a built-up roof must seal absolutely. When leaks develop, they're often at joint areas or at places where the roofing is punctured by vents or soil stacks.

Finding the right roof for your home can be a challenge. Consider your budget, the existing roof and the costs for repairs before settling on anything. That way, you could save some money and get a roof that lasts a long time.