Roof pitch, sometimes referred to as slope, is the measurement of the angle of your roof. It tells you how steep your roof is, but it’s also a vital measurement in determining which types of roofing materials will work effectively to protect your home.
How Is Pitch Expressed?
Pitch is a measurement of the vertical rise by the horizontal run. For example, if the roof rises four inches every foot, it would be described as 4:12, since it has a four-inch rise for every 12 inches of distance.
Categories of Pitches
Flat roofs, once used chiefly in the commercial market, are gaining popularity in the residential sphere. However, no roof is entirely flat. All roofs must be able to drain water, or else rot and mold will quickly degrade the building material. Flat roofs are those that measure with the smallest possible rise ― 1/4 inch per 12 inch slope. This gives a 2% grade for roof draining.
All roofs should allow the water to drain. If your roof has ponding water, make sure you have a product that can handle it. That’s correct! Products that are approved for ponding water exist! If you don’t have a ponding water approved product, you may have pre-mature roof failure due to the build up of algae and other materials left behind from water which doesn’t drain.
Why Should You Know Your Roof Pitch?
When manufacturers design roofing systems, they clearly mark the range of pitch suitable for the materials. If a roofing contractor installs a system that’s not compatible with the building’s pitch, the warranty may be void, and serious water damage can result.
In general, steeper-sloped roofs last longer because precipitation does not stick around ― it runs off quicker than on a flat-roofed home. Also, the roof is not directly exposed to UV rays as with a flat roof. However, there is a price to pay, as steeper-sloped roofs require more building material for the initial frame construction and additional material due to the increased square footage of the roof itself.
Flat and low-sloped roofs are gaining popularity due to the many products now available to increase energy efficiency and maximize moisture protection, such as residential membranes and more. But flat roofs come with limitations.
Many roofing products are not meant to be installed on slopes lower than 3:12, such as tiles or composition shingles. These roofing materials require a steeper slope in order to effectively shed water.
Talk with Your Roofing Contractor
If your roofing contractor is suggesting a system to you without inquiring about your roof pitch or measuring it, you should switch companies right away. One of the first signs of an amateur contractor or one that completes shoddy work is a lack of knowledge about roof pitch and how it effects the long-term performance of a roofing project.
Talk to Knockout Roofing today and let our professional team measure your roof pitch and make expert recommendations on the range of roofing options available to you.