Radiant Barriers

[davevand]

Anyone have an option on these? They have the foil type and the spray on type. Are they worth the trouble and expense.

 

[m1gunner]

Where are you installing this item?

I am guessung your attic?

 

[rundownfid]

If it is for the attic I am interested in this for mine, sure could use some competent advice. I don't trust myself on this subject.

 

[davevand]

In my attic. They have some DIY spray on, some stuff you just add to your own paint, or some foil that is stapled to the inside of the rafters. Just wondering if anyone has any experience with any of them.

 

[Riccur]

One problem with foil is if it is going to get dusty it will not work as a reflector like it should keep that in mind when you install.

 

[walkinghorse]

From the government, a fact sheet!

http://www.ornl.gov/sci/roofs+...s/radiant/index.html

 

[Spotteddog]

What is your primary reason for considering installation?
Heating or cooling costs? To what rate are the attic and walls currently insulated too? Attic ventilator fans(s)? Your physical location?

 

[davevand]

Just trying to get the utility bills down. I am in Houston so the summer utility bill for AC is very high. I had a ridge vent installed when the roof was replaced a few years ago. I will be adding some more insulation, but I am just trying to keep as much heat out as possible.

 

[Spotteddog]

Dave,
I'm thinking that as far as possible A/C savings go, as long as your level of insulation is currently adequate(?) you may be best off with these?
Insulated windows (with black out shades! Use the shades!)
Whole house fan-which allows you to pull the hot air near your ceiling up and out into your attic.(Leave the bedroom doors open to allow air to be drawn out of them too!)
And last (perhaps most important!)
The whole house fan pulling hot air out of the house displaces the hot (usually 150 + degree air) out of the attic. This can be aided greatly by powered attic ventilators.
If you think about it, it's much easier to get rid of the super heated air in the attic, then to try to insulate against it's effects down in the living area. Or to try cooling it down?
YMMV?

 

[oldRoger]

I have a radiant barrier under my roof, it was state of the art when installed. But it’s hard to do unless you are replacing your roof. It’s a Mylar film placed loosely over the rafters before the roof deck goes down. I have a metal roof, so the deck is really a series of 1X4”. I think that you can do a search for radiant roof barriers and find lots of ideas.

You are in an area where a radiant barrier makes economic sense.It’s entirely passive of course, positive attic ventilation can also add to the effect. I haven’t kept up but You may find solar powered ventilation available, works when the Sun shines which is when you need it

 

[peyton]

Ours was installed, the plywood decking had it already as a component. It is still hot as hell up there and we are discussing adding the attic ventilation.