ROOFING : Asphalt Shingles, Durable Tiles Top List of Materials

Today there’s a wide choice of roofing materials. While all are durable, each has its own advantages and trade-offs.

Here’s a look at two popular choices: cementatious roof tiles and asphalt shingles.

Cementatious roof tiles offer traditional looks combined with the benefit of modern materials. These products are made from cellulose fiber-reinforced portland cement or concrete. They are available in red, black, white, green and gray, and can be molded to look like wood shingles, barrel-shaped tiles or slate.

The strong suit of cementatious roofing tiles is their durability. Because they are a masonry material, they resist weathering, insects and fire. Their nearly impenetrable surface also resists the formation of fungus, and because they are heavy, they resist wind uplift.

Asphalt shingles are the most common roofing material, and they come in two broad categories--organic-based and fiberglass.

Organic base means that the shingles are made of a cellulose mat saturated with asphalt and covered with mineral granules. Fiberglass shingles have a mat of woven glass fiber saturated with asphalt and covered with mineral granules.

Organic shingles have a Class C fire rating while fiberglass shingles have a Class A rating.

An important difference between the two types of shingles is that organic types are more flexible in cold weather than fiberglass types.

The two most common types of asphalt shingle are three-tab (also called a strip shingle) and architectural (also called a laminate shingle).

A three-tab shingle is a rectangular mat with two slots cut in its front edge. The slots provide stress relief as the shingle expands and contracts with the weather. An architectural shingle has a heavy base mat and another mat or sections of mat applied on top of it. Aside from making the shingle heavier and more durable, this construction gives the roof shadow lines and character like a tile or wood roof.

A standard three-tab shingle can be organic- or fiberglass-based. Most architectural shingles have a fiberglass mat, although some are organic.

Finally, there are regional and specialized forms of asphalt roofing, such as a highly wind-resistant shingle called a T-lock. This is a slotted T-shaped shingle that locks to the shingle below and the one above.