The pitch of your home can isn’t a typical or set ratio because there actually isn’t one that will work every time. Your home’s roof pitch will be based on a number of factors, including roofing materials and climate.
So how do you determine which pitch ratio will suit your home structure best? Here are a few things to help you figure it out.
How do you determine pitch?
As mentioned, your roof pitch is a ratio of the amount of the roof’s rise over its run. The rise refers to the roof’s vertical span and the run refers to the horizontal distance. Basically, the pitch describes how much the roof rises for every foot of its run. For instance, if the roof rises four inches for every foot of run, the pitch would be expressed as “4/12,” “4:12,” “4 over 12,” and “4 in 12.”
What are common roof pitches?
For a typical roof pitch to use for a traditional house, you should start with the 4/12 pitch cited above, but anything falling in the range between 4/12 and 9/12 is pretty common. If your pitch is lower, you will see it sporting a slight angle, hence the term low-slope roofs for them. Anything less than 2/12 would be considered flat even if it does still have the slightest of slopes. On the other hand, anything above 9/12 is considered steep-slope.
Which materials are best for which pitches?
While it should be up to you to choose the pitch of your roof, you will have to consider certain factors that may restrict your choice. For instance, extreme pitches aren’t practical for certain roofing materials. Low-slope or flat roofs shouldn’t use asphalt shingles since these are easier for water to infiltrate when used on roofs with a shallow pitch. They are best used for roofs with a conventional pitch. Low-slope roofs do much better with materials such as tar-and-gravel and rubber membrane. These two, however, won’t be practical for steep-slope roofs on account of two reasons: first, they would be hard to install, and second, they are not aesthetically pleasing — something that would be very much visible on a steep roof. Tiles and shingles would be much more suited to highly angled roofs.
What pitch suits the local climate?
There are climate considerations in choosing a pitch for your roof. In places that experience white winters, flat or low-slope roofs are not recommended as snow could accumulate on it and make it cave in. At the same time, neither will steep-slope roofs fare well in snowy places since the snow slides down to the eaves.
Wherever you may be, the safe choice is to stick to the standard roof slope range. Such pitches are popular for a reason, after all.