What Is a Composition Roof and What to Expect as a Customer

roof shingles close-up

Composite roofing describes the art of covering a roof with impenetrable and weatherproof layers of shingles, tar paper, and other substrates. When completed the roof can resist any storm and endure for decades if necessary. Roofs must endure any number of serious weather events, from driving rain to baking sun, and a single hole developing anywhere in the surface puts the whole structure at risk. A composition roof represents one of the strongest and most versatile solutions to these problems yet devised.

What Is a Composition Roof?

A composition roof is a thoroughly modern weather resistant insulating surface meant to cover the top of a free-standing structure. A composition roof generally covers a roof that stands with a medium to steep pitch, or slant, and the structure will last between thirty and fifty years with one installation. This roofing type is known as “composition” because the roof is composed of several layers of intermingling types of materials.

What Goes Into a Composition Roof?

vintage roof shingles made from wood

Asphalt, fiberglass, roofing tar, gravel and even small amounts of asbestos go into the dense, fibrous sheets of shingles composing the first layer of the roof. Lying beneath this heavy sheet of shingles you will find layers of tar paper, Tyvek house wrap, heavy sheets of particleboard and other laminated layers of construction. Once the roof is in place, it delivers 30 to 50 years of weather resistant performance.

Advantages of a Composition Roof

Composition roofing is one of the most reliable roofing systems yet devised by mankind. It costs relatively little compared to other roofing types. It is reasonably easy to repair. Composition roof shingles are easy to cut and shape to a particular section of damage or new construction. Furthermore, roofing tar forms an impermeable barrier to seal the edges or any particularly difficult areas. When the time comes, the composition roof can be removed cleanly and easily. What’s more, the completed roof will have excellent properties of insulation. Heat finds it as difficult to pass through the roof as water does, so the house will stay warmer in the winter and cooler in the summer.

The Underlying Structure of a Composite Roof

small cottages with slate roofs

Generally speaking, a composite roof is a sandwich made of five layers of material held together with nails, glue, and tar. On the lowest layer, the foundation of it all, lie the beams, rafters, and load bearing walls. These structures must be strong enough to hold the entire roof during any conceivable weather event. Still, they generally lack any weather resistant qualities whatsoever.

They must be protected at all times, even during construction, or they will suffer damage and possibly require repair. Above the beams and rafters lie wide slabs of particle board or plywood. These flat boards form the surface of the roof. The layers above them will be affixed directly to the boards. Moreover, their contiguous surface provides nearly all the structural integrity of the entire roof. It is essential that the roofing boards must be attached competently and securely. However, they also lack qualities of weather resistance.

Where Composite Roofs Meet the Weather

Once the workers complete the carpentry, composite roofing teams will generally wrap the roof in a thick layer of roof wrap. Tyvek or other plastic membranes make the ideal roof wraps. These thick sheets of plastic form the first layer of waterproofing and also improve the insulation of the building below. However, the house wrap is nowhere near strong enough to stand up to the weather on its own. The layer above it is stronger and heavier and holds the house wrap down.

This is the tar paper, made of a stiff layer of felt and fiberglass that has been thoroughly permeated with tar or a similar oil product. This tried-and-true method of waterproofing will shed gallons of liquid without letting a molecule get through. The workers apply the tar paper down on the roof in overlapping layers. This way, the edge of the top sheet protrudes over the bottom, covering the small holes from the nails that hold the bottom sheet to the roof. As the rain falls, it runs across the paper and finds no chance to seep into a crease or break in the surface. But the rain will very rarely reach the tar paper. This happens because on top of that lies the thickest and toughest layer of all. These are the shingles.

The Composition of Composite Shingles

If you look at a composit roof shingle, then you will find that it is surprisingly complex. It might seem like a little more than a flat sheet about 1/8th of an inch thick. However, composite shingles are made of several layers of precisely mixed substances with generous properties of insulation. They are nearly perfect invulnerability to water.

From the strips of tar glue precisely placed on the bottom edges of the shingle to the colored bits of gravel embedded on the top, composition shingles combine the best of every type of roofing material. They have the weatherproof properties of tar and gravel roofs/ Also, they will actually melt just a little in the heat of the sun to form a nearly perfect surface. They come in several attractive colors, easy to cut, versatile and simple to install. Shingles are the best match to roofs with a medium to steep pitch. One must apply them correctly. Otherwise, the wind may get beneath them and pull them up. Another scenario is that water might seep around the edges or from above.

A professional roofing team can install quality composite roofing in only a few days of work. The finished product might very well live long enough to outlast the house. Professional roofing services are clean, timely and responsive to the needs of the customer. They never leave the roof exposed to the weather. This way, the harm they do to the house and the grounds is always carefully minimized. Best of all, they can guarantee their own work. Are you considering hiring a roofing team or contemplating the work yourself? Either way, knowing more about composition roofs lets you make an informed decision for your roofing needs.

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