Roof Pitch Needed On Patio To Drain Water

18 43 clay tile barrel mission or two piece with special underlayment requirements 2 in 12 2 5 in 12 11 77 clay tile barrel spanish or s shaped.

Roof pitch needed on patio to drain water.

Standard construction tolerances such as the flatness levelness f f f l of the patio slab and the elevation of the drain inlets do not prevent local areas of ponding from occurring. The primary reason roof pitch exists in the first place is to redirect water. An important factor in the lifespan of a deck is its ability to withstand the elements. Water pooling on a patio or pool deck is a potential source of moss or mildew growth concrete staining and dangerous slip hazards.

In 12 0 125 in 12 0 60 clay tile barrel mission or two piece. How to calculate outdoor deck pitch. However you can only use this pitch with built up roofing or specialized synthetic roofing. Thus it is crucial that you plan on providing a method for the concrete patio to drain the excess water that collects on top.

This is the basis for calculating the angle which is approximately a 1 19 degree slope. To safely and efficiently drain water away from your patio i. The roof pitch would be described as a 6 12 pitch. Water often called birdbaths should be expected after a rain due to construction tolerances and normal surface deformations over time.

If that water stays on your patio surface it will cause damage to the structure of the concrete itself and may form a breeding ground for mosquitoes and mold. 18 43 clay tile barrel spanish or s shaped with special underlayment requirements. The pitch of your roof also helps determine the type of materials that can be used on your roofing system. Required roof drainage flow rate in gallons per minute 0 0104 x rainfall rate x roof area.

Smith used a multiplier of 0 0104 in these calculations to convert inches of rain fall per hour into gallons of water per minute per square foot resulting in the following formula for calculating roof drain flow rate. Built up roof coal tar pitch. Water and pest resistant pressure treated lumber is the most common.