Radiant Barriers?

[azsun67]

Has anybody ever installed Radiant Barrier in their attic. If you are not familar with the term it is basically thick TinFoil you install in your attic to help the your house stay cool/hot. I live in AZ and the idea seems sound since the attic temps here in summer are ridiculus. I have read articles that have differing views on their effectiveness. I just went through another summer of high energy usage and would like to help reduce my cost next year with this items and a couple of attic fans.
Thanks for any inputs.

 

[BLAZER PROPHET]

As a long time claims rep, I've come across this several times. In general, most contracting professional think they work effective- IF (and I men "IF") it is properly installed. There appear to be one or two ways to properly install and numerous ways not to. Sometimes to do the job right calls for replacing roof decking & shingles and you MUST have the proper attic ventilation (at 1 or 1.5-150 code). Do not use an attic fan (useless with a radiant barrier).

Lastly, some contractors (the minority) state that radiant barriers cause dry rot when the foil breaks down. Some also state a radiant barrier raises the heat levels too high and break down the roofing material, but my experience is that this is when radiand barriers are improperly installed.

http://www.rimainternational.org/

http://www.ornl.gov/sci/roofs+walls/radiant/rb_tables.html#table1

 

[maxiep]

It really works, but you have to combine it with additional blown-in insulation between the rafter ties. You should have a minimum of R-38.

 

[maxiep]

As BP stated, you have to make sure you have a strong fan blowing hot air out of the attic. I would also add that you need to make sure your roof breathes well through the soffits. The more vents the better.

 

[SlyPokerDog]

It really works, but you have to combine it with additional blown-in insulation between the rafter ties. You should have a minimum of R-38.

Or you could hide a Jewish family in the attic.

Oh wait, I got in trouble this past weekend for not being PC in here. Probably not a good idea to be making Anne Frank jokes. Scratch the Jewish family and go with illegal immigrants.

 

[Nate4Prez]

Let me know what you decide to do and how it works out azsun67? Can you believe it reached 102 this weekend, why do we live here?!

 

[BLAZER PROPHET]

Or you could hide a Jewish family in the attic.

Oh wait, I got in trouble this past weekend for not being PC in here. Probably not a good idea to be making Anne Frank jokes. Scratch the Jewish family and go with illegal immigrants.

The less PC the better, IMHO.

 

[azsun67]

Let me know what you decide to do and how it works out azsun67? Can you believe it reached 102 this weekend, why do we live here?!

We live here since today it is not 102, and we won't see 100+ until next aprilish.

 

[azsun67]

As a long time claims rep, I've come across this several times. In general, most contracting professional think they work effective- IF (and I men "IF") it is properly installed. There appear to be one or two ways to properly install and numerous ways not to. Sometimes to do the job right calls for replacing roof decking & shingles and you MUST have the proper attic ventilation (at 1 or 1.5-150 code). Do not use an attic fan (useless with a radiant barrier).

Lastly, some contractors (the minority) state that radiant barriers cause dry rot when the foil breaks down. Some also state a radiant barrier raises the heat levels too high and break down the roofing material, but my experience is that this is when radiand barriers are improperly installed.

http://www.rimainternational.org/

http://www.ornl.gov/sci/roofs+walls/radiant/rb_tables.html#table1

Why wouldn't I want to combine it with an attic fan, won't that help remove any hot air that does accumulate in the attic. Since I live in AZ I am only worried about keeping the attic cooler. These houses are ridiculus down here, it seems that when it is 70 degrees out in the early evening, you still can't get your house to cool down. You stand by the open window and it is noticibly cooler outside, but you can't seem to get the cool air in. I am trying to see if this is due to the attic being so warm.

 

[azsun67]

Let me know what you decide to do and how it works out azsun67? Can you believe it reached 102 this weekend, why do we live here?!

Don't expect a quick decision on this project from me, i have been thinking about this for years. I am digging into it a little deeper this time and see that it does not look to difficult to install by yourself. I have also seen that the price for the material alone does not seem that bad. Who knows maybe this winter is the year I actually do it. This year my July/Aug electric bill was about $80 dollars higher then it has ever been before so I have a little more motivation then in past years. On a side note I still can't believe that I don't atleast have a solar hot water tank hooked up yet.

 

[BLAZER PROPHET]

Why wouldn't I want to combine it with an attic fan, won't that help remove any hot air that does accumulate in the attic. Since I live in AZ I am only worried about keeping the attic cooler. These houses are ridiculus down here, it seems that when it is 70 degrees out in the early evening, you still can't get your house to cool down. You stand by the open window and it is noticibly cooler outside, but you can't seem to get the cool air in. I am trying to see if this is due to the attic being so warm.

From what I have always been told by various contractors, the attic fans don;t work very well to start with and for some reason do not work with radiant barriers. The idea is for the barrier combined with proper installed ventilation seems to act as a closed system to remove heat. They are also a fire hazard.

 

[azsun67]

From what I have always been told by various contractors, the attic fans don;t work very well to start with and for some reason do not work with radiant barriers. The idea is for the barrier combined with proper installed ventilation seems to act as a closed system to remove heat. They are also a fire hazard.

Ok thanks, I am still reading those links that you provided for me earlier.