Radiant barrier on screen porch roof
I’m considering using a radiant barrier instead of batt insulation in a screen porch roof, the idea being that an uninsulated roof will create absorb heat and create an oven of the space below. Would a radiant barrier be more cost effective than stuffing the rafter bays with batts, and if so, any recommendations as to waht to use?
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Greetings brad,
as a first time poster Welcome to Breaktime.
This post, in response to your question, will bump the thread through the 'recent discussion' listing again.
Perhaps it will catch someones attention that can help you with advice.
Cheers
I am becoming increasingly worried that there isn't enough anxiety in my life
Well, let's try it one more time.
I think it really depends on what your main heat source is. I'm installing radient barrier OSB as my roof sheathing, as the sun here is the primary heater - once the sun goes down the temp drops instantly (So Cal). If you live in the midwest, where you have hot moist air that sticks around after sunset (90 degrees at night - been there) then overall insulation would be a good idea.
Start with the radient barrier, you can always stuff bats in later.
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
I haven't seen the "radiant barrier" OSB here (Boise, Idaho). Anyone ever try just laminating (contact cement or something similar) regular alumnium foil to the underside of plain old vanilla OSB? --Ken
One thing I've heard is that a radiant barrier needs an air space to work well, but am not sure about this because Thermax (rigid insulation) has aluminum on both sides and it's intended to be put right up to sheathing. O've seen some radiant insulation at Lowe's that is like bublle wrap with aluminum foil. Don't know how well it works.
I've seen that bubble wrappy stuff....it is a lot more expensive than a huge roll or two of aluminum foil from Costco..... :-)
Yeah, and not only that, but you can cook your Thanksgiving turkey in the stuff from Cosco!
I suppose you could glue renolds wrap to it :).
http://www.afs-foil.com/
http://www.blueridgecompany.com/cgi-bin/category.cgi?catId=66
These are two I googled up quick. The bubble type basicly provides a built in air gap of 1/4", while the standard perforated sheets (to let out moisture) are backed with plastic sheeting, they recommend an air gap of 3/4". The air gap prevents heat from passing though via direct contact.Rebuilding my home in Cypress, CA
Also a CRX fanatic!