The roof pond is a system that passively incorporates water elements to passively cool and heat the building. Experiments have been run and done by the pioneer Harold Hay on skytherm roofing, however, the true potentials of this system have not be utilized or been well explored by the construction industry. 

The system comprises of 4 parts which are the pond support, water container, pond cover, and a spraying system. The pond support element should possess high thermal conductivity. The pond support can be either metal or reinforced slab with the metal having higher thermal connectivity. The roof pond can be applied in three different methods. Dry (water is contained in plastic bags) such as skytherm house, wet (the plastic bags are sprayed or flooded) such as universidad pompeu fabra, and open (water is contained within the parapet).