ATOT Homeowners: does that attic foil/radiant barrier stuff actually work?

Fausto

Elite Member
Nov 29, 2000
26,521
2
0
It's pretty cheap, my house is not that big, figure I could knock out an install in a weekend or so (provided I don't stroke out in the process).

Your input: I would hear it. :)
 

MagnusTheBrewer

IN MEMORIAM
Jun 19, 2004
24,122
1,594
126
It's pretty cheap, my house is not that big, figure I could knock out an install in a weekend or so (provided I don't stroke out in the process).

Your input: I would hear it. :)

Actual product and your intended usage would be helpful. :)
In general, any extra insulation is helpful. Can't comment on the value til we get more info.
 

Fausto

Elite Member
Nov 29, 2000
26,521
2
0

edro

Lifer
Apr 5, 2002
24,326
68
91
It mainly reflects radiation back into the house or away from the house, correct?
Just like those reflective blankets that look like Pop-Tart wrappers?

I'm sure they work, but radiation is a very very small component of total heat.

Edit: Oh, that is stapled directly to the roof trusses, so it is mainly meant for reflecting the sun's radiation back into the air. I'm sure it helps... but again, how much radiation are the shingles and subroof already absorbing?
 
Last edited:

MagnusTheBrewer

IN MEMORIAM
Jun 19, 2004
24,122
1,594
126
That particular product isn't a vapor barrier but, it will slow down movement of air if humidity is a factor in your area. It does work but, you need to compare cost with expected savings. Spray foam is a better solution but, is more expensive.
 

edro

Lifer
Apr 5, 2002
24,326
68
91
I have a black standing seem metal roof. If this stuff works, I would be interested in it too.
Most of the thermal transfer from the roof into the house is convection and conduction.
I still bet the radiation it blocks in minimal.
 

BoomerD

No Lifer
Feb 26, 2006
65,603
13,981
146
One of my neighbors was going to have "Eagle Shield" installed for about $3500. They kept postponing the installation for various reasons, so I did some checking and found out that they're less than reputable...so he cancelled...and it took him about 3 months to get his deposit back.

Do the attic foil barriers work? Probably...but everything I read says they're no where nearly as effective as the companies claim.
 

sactoking

Diamond Member
Sep 24, 2007
7,623
2,882
136
If you want to go this route some major chemical coating companies sell a spray-on product that is similar to the attic foil. 5 gallons is enough for the average house and IIRC it runs $20-30/gallon, so $100-150 for your house.
 

highland145

Lifer
Oct 12, 2009
43,973
6,334
136
Friend had it done bercause he's using a lot of his attic as storage so adding insulation wasn't a good option. Goes from the soffit to the ridge vent. He's happy. His pocket wasn't.

But insulation is cheap and DIY.
 

honkydory

Member
May 22, 2007
125
1
0
I work at home depot, while we dont sell a lot of the radiant barrier on the roll to insulate, the plywood that has the radiant barrier on it already is a hot item for new construction. So there is merit to the concept, or so i would think.
 

highland145

Lifer
Oct 12, 2009
43,973
6,334
136
If you want to go this route some major chemical coating companies sell a spray-on product that is similar to the attic foil. 5 gallons is enough for the average house and IIRC it runs $20-30/gallon, so $100-150 for your house.
Researched the reflective paint ( goes on the roof sheathing/plywood). At the time, $35/gallon and a construction guy I know thought the life of the shingles would be reduced because of the heat baking them more because it's not passed though. No idea if he's right.

Again, insulation is cheap and DIY.
 

edro

Lifer
Apr 5, 2002
24,326
68
91
The second floor is noticeably hotter in most houses, in the summer.
Do you think it is because heat rises, or because you are closer to the roof?
Or a combination of the two? Which contributes more?

All I know is, my attic is an oven in the summer and there isn't a ton of insulation in the floor of the attic. I bet the reason the second floor is so hot in my house is because I am closer to the attic.
A barrier between the roof and attic would probably be beneficial.
 

ElFenix

Elite Member
Super Moderator
Mar 20, 2000
102,389
8,547
126
It's pretty cheap, my house is not that big, figure I could knock out an install in a weekend or so (provided I don't stroke out in the process).

Your input: I would hear it. :)

why would you be fapping in your attic?




The second floor is noticeably hotter in most houses, in the summer.
Do you think it is because heat rises, or because you are closer to the roof?
Or a combination of the two? Which contributes more?

All I know is, my attic is an oven in the summer and there isn't a ton of insulation in the floor of the attic. I bet the reason the second floor is so hot in my house is because I am closer to the attic.
A barrier between the roof and attic would probably be beneficial.

you need more insulation and probably better venting. soffit and ridge vents. better ventilation helps the insulation work better (the vent is really about keeping moister to a minimum) and has the added bonus of reducing the heat trapped in the attic.
 
Last edited:

richardycc

Diamond Member
Apr 29, 2001
5,719
1
81
I did my attic 2 winters ago, mainly to reduce the attic temp due to the AC blower unit is up in the attic, so during 90+ days, instead of the AC is on all the time and takes forever to cool the 2nd floor, it is on less and cool down the 2nd floor a bit quicker. I will probably need to replace the AC with a bigger unit soon. I got this stuff on ebay for around $150 shipped, it probably dropped my attic summer temp by 20-40degrees.
 

richardycc

Diamond Member
Apr 29, 2001
5,719
1
81
oh I was away last weekend, so the AC was off for 2 days, when I came back, the 2nd floor temp was 82degree at 5pm. If I didn't have this done, the 2nd floor temp would probably be around 86-88degree. yesterday hit was around 91degrees.
 

terry107

Senior member
Dec 8, 2005
891
0
0
It's pretty cheap, my house is not that big, figure I could knock out an install in a weekend or so (provided I don't stroke out in the process).

Your input: I would hear it. :)

Did you ever mess with this? I was looking at adding a radiant barrier as our attic gets to about 800 degrees in the summer.
 

Fausto

Elite Member
Nov 29, 2000
26,521
2
0
Did you ever mess with this? I was looking at adding a radiant barrier as our attic gets to about 800 degrees in the summer.

Nope. Planning to sell the house so not willing to go crawl around in my attic just to give it away in a few months.