Gallons Per Square Foot Of Roof

With a cedar roof make sure you pre wet the roof down with water first.

Gallons per square foot of roof. 400 sq foot roof x 62 248 gallons. Using a 10 000 sq. So a 50 x 20 roof is 600. In those instances you need to break the area down into smaller rectangles.

How do i calculate square footage. For instance an l shaped surface can be broken into 2 smaller rectangles see illustration below. Roof i use about 50 gallons of mix. The collectable rainwater from the roof can be calculated in gallons using this calculator based on the rainfall and area.

Rainwater can be collected from the roofs using the rain water harvesting method. 12 depth a basin or dry stream bed that is approximately 6 feet by 6 feet or a dry stream bed that is 3 feet wide x 11 feet long. I am referencing the square footage of the roof with pitch factored in not the floorplan square footage. Or 0312 gallons per minute sq.

What about non rectangular areas. Code to add this calci to your website. Use one gallon for every 50 square feet of bonded tar and gravel roof and for every 50 to 75 square feet of rolled roofing. The answer is about 623 gallons.

400 square foot roof draining to 1 raingutter downspout. At 12 of depth or 66 sq. Roof area the 3 inch rainfall will produce 18 700 gallons in one hour at the rate of 312 gallons per minute. However a good starting point in my experience is 1 gallon of roof mix covers 100 sq.

For instance if the pool is 3 feet deep 10 feet wide and 20 feet long you would multiply 3 times the product of 10 times 20 to get 600 cubic feet. 6 depth double. To calculate the runoff from any given rainfall. For instance a 7 12 roof pitch means that the roof rises 7 inches for every 12 horizontal inches.

While the amount of primer needed per square foot depends on how porous the current roofing is one gallon of primer covers about 50 to 100 square feet on built up roofs asphalt surfaces and modified bitumen roofs. Outside of the u s a degree angle is typically used. In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches. For example a 3 inch per hour rainfall will build up to a 3 inch depth on a flat roof in one hour at the rate of 1 87 gallons per hour sq.

Take a guess what is the volume of water that runs off a 1 000 square foot roof during a 1 rain storm. So with a 5 000 sq. Take the dimensions of the footprint of your roof and convert them to inches. Gallon to square feet calculator.

248 7 48 33 sq. Step 3 multiply the cubic feet by the amount of water per cubic foot which is 7 48 gallons. Square footage is based on multiplying the length of an area x width of that area.