Roof Deck Slope Ratio

You can divide roofs into these categories.

Roof deck slope ratio.

Tapered slope insulation products can only be used to provide slope if any differences from level in the roof deck are less than the percentage of slope provided by the insulation. We were able to make new crickets to the existing roof membrane providing positive water flow to the drains. The minimum pitch for. Generally such roofs have a pitch ranging from 1 2 12 to 2 12.

The risk of saturated bedding sand is reduced by adequate slope of the roof structure and correct sand gradation. Match roof material and use appropriate slope match the roofing on the covered porch with the main roof. 3 use the divided measurement as the total amount of slope for the deck in inches. A minimum slope of 1 50 1 4 in 12 is strongly recommended.

A ratio of 1 1 62 is known as the golden ratio and therefore the vast majority of roof pitch in degrees charts you see will be working to this ratio at the very least. Roof slope created a simple and great fix to a project were crickets were missed and ponding water became an issue for an owner. If the deck extends 9 feet out from the house the divided measurement is 1 8. Gradation of the bedding sand for pedestrian applications should conform to astm c 33 7 or csa a23 1 fa 1 8.

Often you express roof pitch as the ratio between the rise and the run in the form of x 12. Flat roofs which aren t perfectly flat require a small slope to allow for water runoff. A deck that projects 9 feet out.