Total roof area also affects runoff.
Roof area to gallons.
An inch of rain is not much but it if falls in half an hour it could flood a gutter.
The collectable rainwater from the roof can be calculated in gallons using this calculator based on the rainfall and area.
For all three products allow one gallon of roof coating for every 80 square feet of corrugated metal roof or 100 square feet of smooth metal roofing.
Roof area the 3 inch rainfall will produce 18 700 gallons in one hour at the rate of 312 gallons per minute.
One gallon will cover 50 square feet of foam or modified bitumen roofing concrete or bonded tar and gravel roofing.
0 35 x 1 5 x 900 96 23 4 91 gpm.
Either way you would like to know how much rain has fallen how many gallons have come down from the skies onto your roof yard block or town.
Rainwater can be collected from the roofs using the rain water harvesting method.
1 inch of rainfall in an hour will cover 1 sq ft.
So a 50 x 20 roof is 600 x 240 multiply the roof dimensions by the number of inches of rainfall.
The answer is about 623 gallons.
1 of rain on 1 000 sf roof will yield 623 gallons roof area m 2 x precipitation amount mm amount collected liters other water conservation calculators.
Roof area ft 2 x precipitation amount in x 0 623 amount collected gallons easy formula to remember.
Converting this to gallons per minute per square foot gpm ft 2.
Take the dimensions of the footprint of your roof and convert them to inches.
Rainwater collection calculator in gallons.
To a depth of 1 in 1 hour.
Or 0312 gallons per minute sq.
Just a half inch of rain falling on a 1 000 square foot roof will yield 300 gallons of water.
Highly porous concrete roofs may require more coating for proper coverage.
The runoff q for the roof area in drainage zone a is.
Rain barrel supplies list.
A roof of 1 200 square feet in size will collect more water than one that is 600 square feet.
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.
The runoff for the grass portion of drainage zone a is.
Notice that even though the grass area is nearly 2x that of the roof the roof runoff is nearly 2x that of the.
You might even want to know how many baths you could get from your rainstorm.
Multiply across each row.
To get an idea how much water the roof of your own house might yield use the rainfall harvest calculator above.
Pitch or steepness also is a factor.
Required roof drainage flow rate in gallons per minute 0 0104 x rainfall rate x roof area where rainfall rate is expressed in inches per hour and roof area is given in square feet.
To calculate the runoff from any given rainfall.
1 00 x 1 5 x 500 96 23 7 79 gallons per minute.
The total rainfall and how rapidly it falls will affect the runoff from the roof.
