Roof pitch relates to the slope and inclination angle of a roof in the construction field. The primary purpose of a pitched roof is to redirect rainwater. In general, the pitch of the roof is proportional to the amount of precipitation. Houses in areas of low rainfall frequently have roofs of low pitch while those in areas of high rainfall and snow have steep roofs. It is also the same for areas with large amounts of snow fall.
Knowing the roof pitch of your home is important when you are ordering chimney pipe and the components. The roof pitch is a crucial factor in ordering the right flashing and enough chimney pipe lengths.
Order the Correct Flashing
Roof flashings are manufactured to be compatible with a range of roof pitches. If you don’t know your home’s roof pitch and just take a guess when purchasing a roof flashing you could be very disappointed. If it is not the correct size the flashing will not seal to the roof properly. There will either be large gaps which completely defeat the purpose of a roof flashing. The whole point of a roof flashing is to weather proof where the hole has been cut to pass the chimney pipe through. If the fit is not right you can cause damage to the roofing materials and to the attic space. This is one reason why knowing the roof pitch is important.
Have Proper Drafting
The second reason why knowing the roof pitch is important for chimney pipe installations is because the amount of chimney pipe that you will need is based partly on the roof pitch. The roof pitch and the distance that the pipe will be exiting the roof line is what determines how much pipe is needed to get the right draft. If you have too much or not enough chimney pipe it could cause drafting issues. You may experience backdrafting that brings smoke into the room instead of it flowing up and out like it should. Fires will be difficult to start and keep going, they will also not burn efficiently when there is a drafting issue present.
To measure your roof pitch:
You will need a ladder, a square, and a small handheld level. If you do not have a square you can use two rulers or yard sticks in its place, it would be the same concept. Let’s get started…
- Set your ladder on the side of your house so that you can safely access the down slope edge of the roof. You will not need to get on the roof for this step, just make sure that you can touch the edge of the roof from the ladder.
- Hold a framing square up against the roofline so that the long end of the “L” points toward the peak of the roof and the short end points toward the ground.
- Position the framing square so that the long end meets the edge of the roof at the 12″ mark.
- Using a small handheld level, level the square horizontally.
- Read the measurement on the short end that is pointing at the ground.
- Use the Rise over run formula. If you have a 6/12 roof pitch then the roof slope rises 6 inches in the 12 inch run that was measured.
Measuring the pitch of your roof is a simple task! Knowing the roof pitch plays such important roles in have a chimney system that operates to its full potential that it is not worth taking a guess. It will take you approximately 3-5 minutes to obtain the measurement. Not bad at all!