An illustration of a DIY cooling system in an attic with a bucket of ice, pump, radiator, and blue tarp.

My friend is trying to keep his attic cool, I had the idea of having a large black plastic dustbin filled with cold water, and adding frozen 2ltr bottles of water to act as giant ice cubes which can be easily swapped out for fresh frozen ones when they melt, with a submersible pond pump at the bottom, connected to a feed hose that goes out over the top of the bucket and into a repurposed car radiator. Then the outlet of the car radiator has another hose that returns to the bucket. The whole thing will be assembled inside big a plastic tray (like what comes at the base of a dog cage) to trap any leaks that might happen so they don’t go through his ceiling. I’m thinking we can make a pyramid shape ducting out of tarp, glued in 4 sections along the ends of the radiator and then fed through an 8” hollow ring and folded back on itself and stapled to form a seam that traps the 8”ring inside it. Then some sort of spacer to hold the 8” ring away from the radiator (I’m picturing it looking like a lamp and a lampshade but without the fabric of the shade, just the circular frame held away from the radiator it would be attached with zip ties or something) And if it’s all measured correctly all 4 pieces of tarp would meet at the 8” ring and the seams along the edges of each piece would be stapled together to make a pyramid shape structure out of blue tarp with a 8” opening. Then he can connect the 8” intake duct of the tent onto the DIY air cooler for cool air that has to be drawn See more