reflective insulation

comanche

where i get   these reflective insulation. i live nyc

Mark Eatherton

What's the application?

Reflective foil insulation have been proven bogus numerous times by numerous States Attorney Generals... Are you sure you want to throw your money there?



Go to healthyheating.com and look at the information Mr Bean has assembled on this subject.



ME

furnacefigher15

Home center or building supply

Bogus? For radiant heat usage? I think not.

Mark Eatherton

As Click and Clack say...

BOoOoOogus!



If it weren't for the dust that accumulates on the face of the foil, you might have a valid point.





http://www.healthyheating.com/Page%2055/Page_55_o_bldg_sys.htm



Read the above links, and see if it changes your opinion.



ME



PS, You are new around here. Welcome to The Wall. Tell us about yourself so we know where you stand before you tell us where you sit ;-)



ME

furnacefigher15

You may know me by another name

I sometimes go on hvac talk



Im "heatingman"

comanche

reflective insulation

reflective insulation is posted in greening steam  by Dan Holohan page26

is about insulation barrier ,reflect the radiators radiant heat in to the room

furnacefigher15

Point taken

I see their point. Does not mean it serves no purpose though.



Fact is reflectivity does play a role in radiant transfer. Its why houses with black roofs have hotter attics than ones with white or silver.



Black reflects nothing, but silver reflects a lot.



It all boils down to reflectivity, conductivity, and emissivity.

Tim P._3

has it's uses

I've used it to create an air space between the radiant tubing and the insulation.



Which is to say, I staple it about an inch below the tubing then back it with a fiberglass insulation.



Beyond what reflectivity it may or may not offer, it creates an air barrier and an air space.



As long as you are familiar with it's shortcomings (if you dig deep enough you'll find a certain major manufacturer gives it a R-1.3, even though the facing says anywhere from 4.6 to 8) it has it's uses.  Insulation is not one of them.



A barrier on an attic floor is not a bad thing, as you can sweep it off.  Fortunately, I have not yet reached that degree of insanity.  But I'm working on it.

Mark Eatherton

Vertical application is OK...

Mounted on a wall, behind a radiator, it will work OK as a radiant reflector.



Mounted horizontally, like below a radiant floor heating system, when dust accumulates on its face, it is virtually useless in reflecting radiant energy.



I actually tested this and numerous other insulation below a snowmelt system, and the foil bubble foil was THE worst. I've also tested it in staple up applications at the college I support, and it had an R value that was equal to a 1/2" piece of sheet rock.



In order to reflect radiant energy, the foil must be 99.9% pure, have a relatively smooth surface, and not have ANY dust on its face,and should have a dead air space of 1" on either side of the reflective surface. This is not anything new. They've been employing this reflective technology since nuclear reactors were invented. It's the bubble foil bubble stuff, and its improper promotions telling people that it has "equivalent R values" that got it into trouble with the States AG's. Especially under concrete...



Behind a radiator, it should work better than having no reflective components at all.



ME

Mark Eatherton

I see said the blind man...

I've never been to HVAC talk. Guess I ought to wander away from the Wall some day eh...





Nahhh.... The industry's best hang here ;-) and have done so for a LONG time.



ME

Gordy

Garbage

For the cost in my opinion. Aluminum foil would give the same result behind a radiator. But if you really want to sweeten things up on the stuff ya could say an R1 is 100% better than an R0. It does not take much to get an R1.



Gordy

icesailor

"R" value of Bubble Wrap:

ME,

Those are powerful fighting words around where I work. The building AHJ wanted to see the "R" "Resistive" value of Bubble Wrap. Not the "R", Reflective" value of the stuff. He asked for proof positive for the "Resistive" "R" valve where the thickness of what comes off a roll of reflective bubble wrap was tested by a Nationally recognized testing organization like CSA or UL. None has been produced. Mean while, it is being used where someone rips inside the duct, insulated metal duct or duct board out and replaces it with metal duct, wrapped with bubble wrap. Bubble wrap is equal to R-13 fiberglass bats, don't you know? Especially under slabs after you walk all over it and pop the bubbles. And where it is bent around the corners of the metal duct. Good stuff. Nice install.

I always remember what an electrician friend tells me when I am in a quandary

"They're smart. We're not"

 

Kestrel

Relative R values

Wouldn't R1 be infinitely better than R0?  R2 would be 100% better than R1. 

icesailor

Reflective Reletivity:

True, unless you have been sold R-13 and it is only R-1.