1 of rain on 1 000 sf roof will yield 623 gallons roof area m2 x precipitation amount mm amount collected liters.
Roof rainwater collection system.
To use this calculator input the dimensions of your roof only area connected to rainwater harvesting system and the amount of rainfall in inches.
The good news is most roofing materials are suitable for rainwater harvesting.
There s just a short list of rooftop surfaces that rainwater harvesters should avoid.
While metal roofing or plastic sheeting e g.
The supplies you ll need to make your rainwater collection system can easily be picked up at a hardware or home and garden store.
A first flush diverter is a contraption that redirects the first purge of water coming from the roof during a storm away from the rainwater tank.
Read down the list for info on roofing materials for rainwater harvesting.
Pipe threads so you can access water from your rain barrel.
Greenhouse roof has the highest collection efficiency most surfaces are a ok.
How much rainwater can you harvest from your roof.
A step beyond screens is to add a first flush diverter aka roof washer to your rainwater collection system.
Here s a handy little calculator to help you estimate how much rainwater can you harvest from your roof.
Figure out what you already have on hand then gather the following supplies.