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Roof heat reflective paints

Can anyone tell me if white paint on roofs works just as well at reflecting heat as the expensive ceramic heat-reflective paint?

Thanks muchly, Jessica Walden (HOT South Australia)

Jessica Walden
- Adelaide, SA, Australia
2002

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2003

Hi Jessica,

According to the results of the experiment conducted at the University of Nevada, Mechanical Engineering Department, there is a significant increase in energy usage (50%>) when regular outdoor paint is used, compared to ceramic paint.

MONTH       PAINT         Ceramic       % DIFF 
JUNE        167.99        117.21        43.32 
JULY        101.81         69.68        46.11 
AUGUST      175.72        109.72        60.15 
SEPTEMBER    63.16         39.55        59.69 
TOTALS      508.68 Watts  336.16 Watts  51.32%
 

To cut costs try a heat reflecting ceramic powder that can be added to any paint making that paint an insulating coating for your roof. I hope this is of some help,

Regards,

Dr Con Lozanovski
- Melbourne, Victoria, Australia

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2005

There is a Technology that can provide a negative heat load to the roof of a building, it is known as a "Selective Surface", it is not an insulator like the ceramic coating people claim.
This technology is more so used in commercial buildings where there is a heavy A/C load, and in projects done with a major retailer a 50% drop in power consumption was found on the A/C plant, not bad considering the A/C cools the interior as well as incoming air, on this project the main a/c use was for cooling the hot summer air in the exchange. On a house environment it will keep the internal maximum temperature 4 to 5 degs below external shade ambient. This is only achieved through air conditioning in a normal environment.
Regards

Ted Lehmann
- Sydney, NSW

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Ed. note: Ted, do you also have a university study we can extract here, showing those negative watts/square foot ratings?

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2005

I am also looking for a heat selective roofing paint. I have found what seems to be a relevant product, but this is in Australia, so I would like a source in Thailand as the coverage is listed at 2-2.5 m2/litre. - a large volume to send from Australia to rural Thailand to paint a roof.
All ideas welcome!

Hugh Milner
water resource engineer - Buri Ram, Thailand

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Dear Mr. Milner,
We recommend you to use ceramic paints for roof-top coating. On metal roof, the temperature difference of coated and uncoated surface can be greater than 10 degrees C. during summer months.

Chalermchai Su-uthai
- Bangkok, Thailand
2006

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Are there effective Heat reflective paint products that can be applied inside the attic of home with a traditional asphalt shingle roof?

Are there any effective Heat reflective paint products that can be applied to the outside ( on the shingles)?

Mark Ahlert
- Houston, Texas
2006

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Hi, Mark. There are paints that can be applied inside the attic that claim to reduce energy costs. I'm not personally disposed to believe it, but I don't have any experience with it to back up my intuition.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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Hi

I am an expat and I live in the tropics in the far east about 150 miles from the equator.I was hoping someone might know if I can paint exterior walls with a known and dependable heat resistant paint product.It gets extremely hot and humid here! Thanks.

Gearoid Campbell
property refurbisher - Kuala Lumpur,Selangor, Malaysia
September 4, 2009