An Introduction to Roof Shingles
In most posts, when we're talking about shingles, we are talking about the classic asphalt shingle. The meaning of a shingle is a thinnish piece of material that is laid one on top of another. There are shingles made out of a variety of materials including asphalt, slate, and cedar.
Originally (think 1880s to 1950's) in the Pacific Northwest, houses were shingled with cedar aka cedar shake. Cedar is a really durable material, particularly the high quality material that was used during that time that is no longer available. If you currently have a cedar shingle house, check out this post to learn how to help maintain it. There are also companies that specialize in cedar shake houses. We do cedar shingles as well and if you're looking for someone who's committed their whole company to cedar, here's one great company in the Portland Area: https://www.cedartechroofcare.com/
Slate shingles are quarried and very carefully installed using copper nails. They are extremely long lasting but also very very fragile. They crack very easily and there's no way you can walk on them. Speciality roofers handle slate shingles in the Portland area. You can expect a slate roof to cost $100,000 or more.
A new product has arrived in recent years that are called composite shingles. They look cedar, tile, or slate but are created using an injection moulding process. They are extremely durable and much easier to install and repair. They also cost less! We proudly carry Brava products.
Asphalt shingles are the "go to" shingle product for most homes in the United States. They are durable, relatively inexpensive, and proven. Modern asphalt shingles are composed of three layers. First is the fiber glass mat, then the asphalt layer, and finally a rock like aggrigate on top.
There has been a lot of technological advancement since the invention of asphalt shingles. Some companies include rubberized elements to make the shingles less brittle, making them more resistant to impact and easier to install in colder weather. Great for the Pacific Northwest! Another advancement is the inclusion of heat reflective technology to stop heat gain. This is an important consideration as the summers are getting hotter here in Portland. It also opens up more color choices, black is not such a hot color anymore! One other advancement to note is the addition of herbicidal compounds like copper in the top aggregate, stoping the growth of moss, lichen, and black algae for up to 15 years.
Asphalt Shingle Styles
Twenty years ago, a style called "three tab" was extremeley popular. Three tab gets its name because there are three tabs in the shingle. Whenever you see them on roofs here in Portland, typically the roof is older. When in good condition, they lay very flat.
Today, you'll mostly see a style of asphalt shingled called "architectural". It is designed to have some more physical texture and mottled colors. It is generally thicker product than three tab shingles.
The third common asphalt shingle style you'll see is "presidential". Presidential is a branded term for a shingle style created by CertainTeed. They are the only ones that can use that term for advertising purposes, but the word has almost become synonymous with the style. Similar to saying Kleenex for tissue. The non branded name is dimensional. Dimensional shingles are thicker still and styled to mimic the texture of original cedar shingles. They are more expensive than architectural shingles.
You can also get really interesting and beautiful looking asphalt shingle shapes. Certain buildings ask for a little extra in their styling. This is a church we reshingled up in Hood River, Oregon, that was just screaming for something a little different. The parishioners also use this church as a venue for destination weddings and the special shingles give it a interesting accent.
One feature of asphalt shingles to keep in mind is the sealing strip on each shingle. The shingles are laid on top of each other in rows and the sealing strip adheres to the next layer. This creates a bond that prevents wind (remember the destructive power of wind!) from catching the edge of the shingles, lifting them up, and ripping them out. This bond also helps create more of a resistance to water infiltration.
When we do inspections, one of the things we look for is if that seal has been broken. This can happen because of age, improper installation, or moss. Yes moss! Moss is extremely damaging to roofs. We'll come back to moss.
Squares - Bundles - Rolls
Another thing we'll touch on about shingles is how useful it is to talk about roofing materials in terms of squares. Each different style of shingle can have a different thickness. One bundle (shingles come in bundles) might have 20 shingles while another might have 30 shingles. Brad West on Quora describes why we use the measurement square really well.
This term is useful because shingles and roofing can come in different sizes. If I have a bundle of shingles that equals one square and you have a bundle that equals one square we know that they will both cover a 10 ft by 10 ft area. My bundle of smaller shingles might have 50 shingles. Your bundle of larger shingles might have 23 shingles. They will both cover 1 square so the actual size of the shingles is not important. Roofing can also come in rolls and a typical roll is one square. Knowing this makes it easy to compare roofing costs.
Hip and Ridge Shingles
During the era of three tab shingles, roofers would cut them into piec
es to cap anywhere the roof came to a point. There are two main locations that come to a point on a roof. A hip and a ridge. Generally, a ridge is straight across and is the highest point on a roof while a hip slopes downwards and is
lower than a ridge. Today, some roofers in other parts of the country continue to use three tab shingles to make their own cap shingles for hips and ridges. Here in Portland and the Pacific Northwest, it is more typical to buy special purpose hip & ridge shingles shingles.
There's a surprising amount of diversity within asphalt shingles. We did a lot of research and concluded that we would happily install whatever our customers wanted on their roofs, but we would recommend Malarkey shingles. If you'd like to read about our selection process check those articles out.