Architectural shingles are one of the best roofing materials for your home. Although they are all made from a mixture of fiberglass and asphalt, architectural shingles are different from dimensional or three tab shingles in texture, weight, thickness, and profile.
Installing a ridge cap on an architectural shingle roof is very important, as is the vent that it covers. However, an improperly capped vent may not function as it should, and can actually cause the problem it is designed to prevent.
Knowing which ridge cap you can use for an architectural roof, and which you should not is vitally important to the longevity of the roof. Today, we will discuss what a ridge cap is, what it does, where it goes, and why.
What Is a Ridge Cap Shingle?
A ridge cap shingle is a small shingle, usually about ⅓ to ½ the size of a regular shingle, that connects two sides of a roof together. A simple example would be the roof on a standard ranch-style home. Ranch styles homes usually have a two-sided gable roof, meaning they will have two equal sides that meet at the top. Where these two sides meet is known as the ridge.
When the two sides of the roof meet at the ridge, one side stops about 2” short of the top, as does the other side. By stopping short, a 4” gap is created between the two halves of the roof. Air in the attic, heated by solar radiation, escapes through this gap to prevent the heat from damaging your roof and heating the home.
Of course, you can’t leave a four- inch opening in your roof, so it is covered with a roof vent, which is then covered by the ridge cap shingles. The ridge cap is installed so that the only exposed fasteners are used to attach the last ridge cap shingle. All of the other fasteners will be covered by the next ridge cap shingle.
Why Making Ridge Cap Shingles From Architectural Shingles Is Not a Good Idea
Ridge cap shingles are traditionally made by dissecting a three tab shingle into three sections. Three tab shingles are already notched in these locations and perfectly flat, making them perfect for the job.
The thin profile of a three tab shingle also allows it to make the bend over the ridge without breaking. Three tab shingles are also consistent and symmetrical, so there is very little waste when creating ridge cap shingles from them.
Architectural shingles, however, take many forms and profiles, so using them as a ridge cap often leads to waste and ill-fitting ridge cap shingles. Architectural shingles are also thick and heavy, so they tend to break instead of bend over a steep angle, like a ridge on a roof
Read our architectural shingles cost guide if you’re thinking about going with that option for your roof.
Why Shouldn’t I Make Ridge Caps From Architectural Shingles?
The Colors May Not Match
Not all manufacturers offer the same colors in both architectural and three tab shingles. As a result, some roofers began trying the same technique of dissecting architectural shingles for ridge caps, only using architectural shingles instead of three tab shingles. Doing so guaranteed a color match, but because architectural shingles are designed to lay flat, this caused a problem.
Architectural Shingles Are More Rigid
Ridge cap shingles must be able to flex or bend to conform to the angle of the ridge. The greater the pitch, the steeper the angle becomes. Three tab shingles are quite thin compared to dimensional or architectural shingles, so they can make this bend easily without breaking, especially after the sun warms them up.
However, an architectural shingle is much thicker and more rigid than a three tab shingle, or even a dimensional shingle. Most roofs are built to a 6:12 slope, which means the ridge caps have to bend over 50 degrees without breaking or cracking. A roof with an 8:12 or even 10:12 pitch requires the ridge cap to bend even more, making architectural shingles a poor choice.
Architectural Shingles Are Not Always Uniform
The lack of flexibility isn’t the only reason you shouldn’t use an architectural shingle as a ridge cap. Architectural shingles are not only thicker than a regular shingle, they are also not uniformly manufactured. Architectural shingles are often designed this way to avoid forming a pattern, as many are designed to resemble wood shingles or slate tiles.
Ridge cap shingles should lie as flat as possible on the ridge to avoid creating a gap that could cause a leak. Wind can easily lift a ridge cap shingle that does not firmly contact the shingle below it. Architectural shingles vary in thickness to achieve the texture they provide. When one ridge cap shingle overlaps the next one, it should seal tightly.
Because an architectural shingle is often designed to look random and not form a pattern, it makes finding a flat one very difficult. Using architectural shingles as a ridge cap also wastes material, because even if you find one you can dissect for a ridge cap, the rest of the single is probably useless and will be discarded.
How Do I Make a Ridge Cap Shingle For an Architectural Roof?
You will normally have two options for a ridge cap shingle. As mentioned previously, you can either make them a three tab shingle, or you can purchase matching ridge caps for your particular architectural shingles. If the color of your shingles is fairly common, you can probably use a three tab shingle in the same color.
Architectural shingles are available in many colors and textures, so confirm that the manufacturer makes both architectural shingles and three tab shingles in the color you need. Otherwise, you may find the color of the shingles is quite different from the ridge cap.
Most manufacturers use a color name, like charcoal, or desert brown to differentiate the various shades they offer. Some color names, like Gray, are used by all shingle manufacturers so make sure you purchase the same brand in both shingles, not just the color name.
Professional roofers will make sure they buy the same brand in both shingles, because common colors like brown, gray, and tan are available in many different shades. A tan color in one brand might be closer to desert gray in another, but the color will be consistent within a brand regardless of what shingle design uses it.
Although there may be a slight color difference between the three tab shingle and the architectural shingle, the ridge caps are usually so far from view any difference in shade is unnoticeable. However, if you mix two brands of shingles, you may get a decent match and you might not.
Having said that, all fiberglass/asphalt shingles are produced by a dye lot, meaning the colors can be slightly different from production run to production run. For this reason, always select your three tab shingles from the same dye lot. The lot number will be on the end of the bundle of shingles, so make sure to purchase bundles with matching dye lot numbers.
Purchase Ridge Cap Shingles
Typically, the best method is to simply purchase matching ridge cap shingles when you buy your architectural shingles. In most cases, these ridge caps will be less expensive than using three tab shingles because you can buy them in smaller quantities. Plus, the ridge cap shingles will match the architectural shingle color, so they will also look and fit as they were designed.
Make Your Own Ridge Cap From a Three Tab Shingle
Making ridge cap shingles from three tab shingles is simple. You can use 20, 25, or even 30 year three tab shingles as a ridge cap, by separating the tabs with a sharp blade. Only about half of a ridge cap shingle is visible after installation, so they install very easily with just a couple of roofing tacks.
Most roofers use a triangle square, sometimes called a speed square and a hook bladed utility knife to make the ridge caps. You can also use a simple carpenter’s square, if that’s what you have on hand. Simply place one side along the upper edge of the shingle, and use the other side as a guide for the blade.
What Is a Hook Blade For a Utility Knife?
A hook blade is a tool used mostly by roofers, so they may be unfamiliar. Hook blades fit in a utility knife just like a regular blade, but the sharp edge is not straight. A sharp edge is hook shaped and designed to cut through the edge of a material, not the surface as a normal blade would. Hook blades allow roofers to cut several shingles at once, speeding up the process.
What Is a Ridge Vent?
A ridge vent is an air permeable material that separates the ridge of the roof from the ridge cap shingles. As described earlier, roofs are required to have some form of ventilation to prevent the build-up of heat. The ventilation usually comes in the form of a gable vent, or the ridge vent working in coordination with the soffit vents.
This design ensures complete air circulation within the roof system (and attic) as required by building code. Sometimes ridge vents are made from rigid aluminum with rubber stoppers on each end. Some are made from corrugated plastic, while still others are made from weather resistant mesh.
Rigid Aluminum Ridge Vent
Rigid aluminum ridge vents are less common in modern construction, but they are still used on starter homes and remodeling projects. Birds tend to destroy the rubber end caps used with aluminum ridge vents, so they tend to leak without proper maintenance.
Aluminum ridge caps are also surface mounted, so they tend to stand out visually. Most aluminum ridge vents are either brown or black, so they contrast sharply with a lighter colored roof. Aluminum ridge vents are also easily dented, so impacts from falling tree limbs can damage them beyond repair.
Corrugated Plastic Ridge Vent
Corrugated plastic ridge vents work very well and have the advantage of being covered by the ridge cap shingles. Corrugated plastic ridge vents are inexpensive and eliminate the need for the rubber end caps. Corrugated plastic ridge vents are usually sold in rolls of about 25 feet, which can be added to, or cut to size.
Corrugated ridge vents are very durable, and can take a strike without damage. Because corrugated ridge vents are made from plastic, they are also very resistant to moisture and UV damage. Corrugated ridge vents are generally hidden from view under the ridge cap shingles, as they are thin and conform easily to the angle of the ridge.
Weather Resistant Mesh Ridge Vent
Generally, the best ridge vent design uses a weather resistant mesh formed into a long narrow sheet. Mesh ridge vent is installed over the vent opening in the roof and then the ridge cap shingles are nailed directly through the vent and into the roof decking. This process eliminates all but two exposed fasteners, which are sealed with roof cement.
Mesh ridge vent has a texture similar to a kitchen pot scrubbing pad. The mesh design allows air to flow through it easily, regardless of the shape it takes. Mesh ridge vents are so pliable they can be literally folded and still perform perfectly, making them ideal for hip style roofs with steep angles.