Hot tin roof

[keiregan]

Any recommendations for reflective roof paint? Early 90's hpm home. House gets so hot. Looking to cool it down.

[kalakoa]

Cover the roof with solar panels. Problem solved!

Otherwise, there's always the white elastomeric stuff from Depot...

[Rob Tucker]

Try to do it once and do it right. Think beyond the word paint and research liquid ceramics. Very effective in heat deflection. It is now actually kinda old technology derived from the space shuttle heat shields.

Some test data I was studying showed how a piece of metal on a 90 degree day can get up to 160 degrees. Coated with a liquid ceramic coating that same metal under the same conditions went from 90 degrees to 96 degrees.

Good luck. Let me know what you find out.

[bluesboy]

here's a cool flier from a study they did in florida, all about energy efficiency, and keeping your roof cool.

http://www.nrel.gov/docs/fy05osti/37547.pdf

any kind of panels on your roof do serve the additional purpose of absorbing heat, as well.

[keiregan]

quote:

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Originally posted by kalakoa

Cover the roof with solar panels. Problem solved!

Otherwise, there's always the white elastomeric stuff from Depot...

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Love that solar idea. definitely in the plans down the road. As i look around the sub divisions i don't see many homes with panels or reflective coating on the roofs. going to work on ventilation ideas as well. This home was built with no thoughts on cooling it down. Just a metal box.

[keiregan]

quote:

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Originally posted by bluesboy

here's a cool flier from a study they did in florida, all about energy efficiency, and keeping your roof cool.

http://www.nrel.gov/docs/fy05osti/37547.pdf

any kind of panels on your roof do serve the additional purpose of absorbing heat, as well.

---

Some good info in there for sure. I lived in florida for awhile. Every house massive ac units. not cost effective in hawaii. White roof for sure, solar water heater awesome. my place has open beam ceiling with gable windows.
Other half low ceiling. no insulation in the attic. you could bake cookies it so hot in there. so cool the roof vent the attic somehow. try to figure out how to vent open beam ceiling.

[terracore]

I installed a solar powered fan in our ceiling. It blows the air from the house into the attic where it displaces the hot air. This scheme is usually called a "whole house fan" because it brings outdoor air into the house and also displaces the hot air in the attic, so it performs two functions unlike an attic fan. Because I didn't want to cut a hole in my ceiling I cut a hole for the fan into a piece of wood that was cut to the same size as the drywall for the attic hatch and replaced the attic hatch with my homemade concoction. I used to be able to feel the heat coming off our ceiling, now I do not. It still gets really hot up there but not as bad. Since it is solar powered, when the roof is getting the most amount of sun is when the fan spins the fastest.

Hawaii is offering energy rebates on whole house fans and attic fans: https://hawaiienergy.com/for-homes/rebates/hvac

" Whole House Fan

Get a $75 rebate on a whole house fan that draws cooler, outside air through your living space by pushing the hot air out of the home and out of the attic vents, creating a cooling breeze."

ETA: I bought mine on eBay. I think it was a 30 watt solar panel and a 12v fan with the pair rated to move 1500 cubic feet of air per minute at full sun.

[Cagary]

quote:

---

Originally posted by Rob Tucker

Try to do it once and do it right. Think beyond the word paint and research liquid ceramics. Very effective in heat deflection. It is now actually kinda old technology derived from the space shuttle heat shields.

Some test data I was studying showed how a piece of metal on a 90 degree day can get up to 160 degrees. Coated with a liquid ceramic coating that same metal under the same conditions went from 90 degrees to 96 degrees.

Good luck. Let me know what you find out.

---

Do these liquid ceramics pollute the rain water going into a catchment tank?

-Veritas odium parit”(Terence 195–159 BC))-"Truth begets hatred".

[kalakoa]

Obligatory: can I buy these liquid ceramics on-island?

[EightFingers]

Bugs don't like living under a hot roof!