Any one heard of this ?

[Cliff Rohrabacher]

http://hytechsales.com/insulating_paint_additives.html

[Stuart Johnson]

There is a company advertising a spray paint for the inside of your roof that is suppose to reflect back the heat. I guess it might reflect heat but don't understand how if it is sprayed on the inside. I probably don't understand the idea but it seems if he sun is heating up the attic spraying the inside won't reflect the sun. If it does somehow send the heat back out why wouldn't this be bad for the shingles. For example if you have 100 degrees penetrating the roof and you then reflect 50 back doesn't that mean you have 150 degrees passing through?

[Greg Peterson]

I think the idea is that the spray will reflect some of the thermal energy, not sunlight.

"For example if you have 100 degrees penetrating the roof and you then reflect 50 back doesn't that mean you have 150 degrees passing through?"

I'm not a physicist (but I did sleep in a Holiday Inn Express!), but something tells me that reflecting back 50% of the heat wouldn't raise the overall temperature. If it did, this would solve a huge energy problem. Something about equilibrium in an open system and such.

[Pat Germain]

Sounds like a scam to me. And it sounds very similar to a product being marketed back in the 1980's. This product was a kind of foil attic barrier which claimed to do the same thing. Consumer's Union tested it and found if, and only if, the foil barrier was installed with absolutely no gaps, it sorta did something. Since the foil barrier was almost always installed by novices working for minimum wage, it was typically a complete waste of time and money.

If you want to cool your attic, electric attic fans are inexpensive and very effective. They even have a thermostat that turns on the fan when necessary and shuts it off when unnecessary.

[Russ Filtz]

Theoretically possible I guess if the inner surface (in contact with the wood) of the paint was highly reflective and the paint layer itself was a very good insulator. I agree that trapping this heat inside the roof would be bad for the shingles. You'd be better off painting your roof white!

I like attic fans too, not the whole house variety though. I think the whole house fans have been shown to not be really energy efficient in cooling. May be wrong though. Everyone had attic fans when I lived in the midwest, but down here in Florida, no one uses them! I asked about it and didn't seem to get any clear answers. Of course the builders are cheap down here and they also call it Flori-DUH for a reason! Pretty much hate this State on several levels! Wife would kill me if we move again though.

[keith ouellette]

We have a product being used in florida. It is a thermal reflector (looks like a thin silver thermal blanket). It is put in the attic space along the trusses and reflects the heat back out. My neighbor has it and I know from experiance that it works very well. I would assume the paint product would try (i said try) to work the same way. The thing I am talking about works so well, wasn't expensive, and was easy to install. I am going to email him to find out more and will post it later.

[Jon Lanier]

Now if they could just do that and make it a sound barrier paint. Wooo hoooo!

[Randy Denby]

ASHRAE (american society of heating, refrigeration ,air conditioning engineers ) did a study on this 20 or more years ago. To the point...it dont work. Heat is transfered three ways: radiation, convection, conduction. Since the reflector is in the shade of the attic,pretty much negating the reflection and going straight to conducted transfer....
The main thing the sheet material sold back in the 80's (foil) would help with was sealing the air space below....and this can be done with alot of different types of sheet material. But then , this causes problems in that the vapor barrier is now on the wrong side of the insulated space/insulation , and will trap moisture in the insulation.
So,temp difference always seeks equilibrium, insulation is still the best way to slow it down. Reflection works best if it is the first line of defense,Not hidden behind the shingles/roof ply from the sun.... then insulation.Dark shingles/roofs are the enemy, shade the house and /or suck the hot air out of the attic
So in reflection.....I need a cold beverage to seek equilibrium in my hot self ....might take more than one:D

[John Schreiber]

http://hytechsales.com/insulating_paint_additives.html
What they describe on the website is quite different from roof insulation. Their vacuum filled (emptied) micro balls "could" work, but I couldn't find any thing about it except for the claims made by the makers/distributors. An external review of some sort would make me more inclined to believe.

[keith ouellette]

ASHRAE (american society of heating, refrigeration ,air conditioning engineers ) did a study on this 20 or more years ago. To the point...it dont work. Heat is transfered three ways: radiation, convection, conduction. Since the reflector is in the shade of the attic,pretty much negating the reflection and going straight to conducted transfer....
The main thing the sheet material sold back in the 80's (foil) would help with was sealing the air space below....and this can be done with alot of different types of sheet material. But then , this causes problems in that the vapor barrier is now on the wrong side of the insulated space/insulation , and will trap moisture in the insulation.
So,temp difference always seeks equilibrium, insulation is still the best way to slow it down. Reflection works best if it is the first line of defense,Not hidden behind the shingles/roof ply from the sun.... then insulation.Dark shingles/roofs are the enemy, shade the house and /or suck the hot air out of the attic
So in reflection.....I need a cold beverage to seek equilibrium in my hot self ....might take more than one:D

I know for a fact the product I described works very well. It is my understaning heat radiation can be reflected after it passes through an object . The silver shield radiant barrier being installed down here is two thin to work as insillation and the attic space is much much cooler with it than without it. I can't explain exactly how it works or why it seems to be in variance to the study you described (I remember sheathing with a silver layer on its back and it wasn't used long) but I can feel the temp. differance. I don't think the paint product will work as well because it would be like the foil used before. The big differance between the two products is that one is touching the sheathing and the other is allowing an air gap between the sheathing and the barrier. This stops the heat conduction that made the previous products not work.

[Greg Crawford]

There is a book I found (now out of print) called the Superinsulated Home Book, written by J. D. Ned Nissan that was (at the time) President of Energy Design Associates, and Dr. Guatam Dutt of Princton University's Center for Energy and Environmental Studies. This goes into great detail about how heat transfers, especially radiation ("space blankets" live survivalists carry are based on the energy radiation principle). I've looked into the "radiant barrier" paint and paint additives, and it sounds like it goes along with the physics presented in the book and could help. There's another company, http://www.koolcoat.com/index.html with a lot of glowing testimonials, plus it's not too expensive and can be added to any paint. I'm thinking of trying it on my West facing garage door that heats up my shop every afternoon.

BTW, one company had a demonstration of putting a torch to 2 raw eggs, one treated with their product and one not. The untreated egg cooked, while the other didn't.

I guess the best way to find out is to find an inexpensive way to try it.

[Ben Gastfriend]

I've heard of this and they just used it on a church near my school, but the way it was used is It was put ONTOP of the shingles. It's supposed to reflect back the thermal energy because it's white, instead of black, which absorbs it all. Just like a black car heats up faster than a white car on a sunny day. Seems to me like it would work.

[keith ouellette]

I've heard of this and they just used it on a church near my school, but the way it was used is It was put ONTOP of the shingles. It's supposed to reflect back the thermal energy because it's white, instead of black, which absorbs it all. Just like a black car heats up faster than a white car on a sunny day. Seems to me like it would work.

I think the product you are referring to is called kool seal. I have seen it also but do not know how well it works. This barrier paint is a little different.