As an art school graduate, it is almost natural to have no stable source of income. I have a studio on a top floor of an old brick building, and because the rooftop gets lots of sun all day and there seems barely any insulation between the ceiling and the rooftop, heat dissipation really kills me in the studio in summertime.
Yeah, turning on AC all day would make the space much more livable but that would use so much energy wasted if I don't do anything about the sizzling rooftop.
So here it comes: Passive, No tech(almost), cooling for rooftop and the space below.
It is a very simple and cheap(to make and to use) i'ble, and you can apply to pretty much anywhere with large surface area for evaporation!
Step 1: Science Behind This Simple Project
This i'ble uses the principle called "evaporative cooling". When liquid turns into vapor it requires energy - in this case surrounding heat - and where the liquid evaporates is left with cooler temperature. This passive technology has been used for thousands of years, and still being used in many applications. Misting and evaporative coolers are good examples of this. Also your body sweats works the same way biologically as sweat dries out, surface of your skin is cooler. Rubbing alcohol evaporates much faster than water, thus it feels cooler when you blow it on your skin.
For more information for you curious heads, check out this Wikipedia page.
This video explains evaporation process concisely.
Step 2: Mateials
I had 4 meters of 19mm ID hose laying around so I started from there.
4 meters (16') of 19mm ID flexible hose
10 meters (33') of 16mm ID flexible hose
3mm drill bit
a few zip ties
(optional) hose clamp, if you want to detach the hose quickly.
hose adapters (3d printed)
I bought 16mm hose because it is cheaper than 19mm and the weight of the water it has to hold is less.
Total cost of material is around $10 or less.
Step 3: Drill Water Outlets
I used 3mm drill bit and made a thru-hole every 30cm (1 foot)
If the holes are too small (also in quantity) water pressure inside the hose can get pretty high and burst at some point. If the holes are too many and large, water may not get till the end of the hose, so don't make too large or too many, you can always make more if it isn't enough.
Step 4: Hose Adaptor
These are hose barbs and connector to a shower head in the studio.
Barbs diameters are 19mm and 16mm, and thread pitch is 1.7mm.
Printed with ABS and PLA with 0.2mm layer height and they work great.
Step 5: Connect Things Where It Needs to Be Connected
Use zip ties as hose clamps.
Check water pressure and adjust number of outlets.
Place hose strategically to cover most area. In my case, rooftop is very uneven so I placed it on the highest spot to let water travel the most area.
Step 6: Results
15 minutes after watering (for 3 minutes) temperature dropped dramatically. I didn't expect this much of temperature drop but it works pretty well.
Thanks for reading!