Areas where water is in short supply.
Water on the roof for cooling.
The majority of time older homes do not have enough roof vents to help cool the attic in summer.
As water evaporates from the pond heat is consumed.
At its lowest tech a roof misting system can be little more than a garden hose set to the mist setting and aimed across the roof.
There should be 1 square foot of vent for every 300 square feet of floor space.
Ambient indoor temperature is approx.
50 radiant heat from surface radiation and 50 air temperature.
In the simplest form this involves placing a pond on the building roof.
This cools the roof which acts as a heat sink and absorbs heat from the interior of the building.
Cooling with liquid water running off from a sprinkler is not efficient but evaporative cooling from a small amount of water like a periodic sprinkle is very efficient.
Yes you can spray your roof to help cool it down but that will only cool the shingles for a short time and be a large waste of water.
Prototype for a evaporative roof for radiant cooling cherry valley ca usa reconsidering comfort.
Also called an evaporative cooling system a roof misting system lowers surface temperatures by spraying an extremely small amount of water across the roof allowing the water to cool the roof as it evaporates.
Yes water on the roof will help cool it.
1 gallon of water consumes 8000 btu as it evaporates.
These systems provide cooling by spraying the water evaporates and cools the surface.