# rafter heat barriers



## Thurman (Feb 9, 2009)

I think what the inspector was meaning was that the insulation was too close to the soffit and prevented proper natural ventilation. There are products out there which are made to do this. I find them in the area where the insulation is usually stocked, most are made of a styrofoam material, much like egg cartons, and are made to be stapled or nailed onto the rafters to prevent the insulation from blocking the soffit vents and allows air to move between these shields and the roof. They can be a DIY project. As far as those employees in the bigbox store: they are just employees, I've met very few of them that are trained in anything. They needed that job just like many other do nowdays. I would suggest buying a couple of these, install them yourself and then decide if you want to go the entire project. Good Luck, David


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## Ed the Roofer (Jan 27, 2007)

I tried replying to this earlier, but my home keyboard started skipping letters.

I believe what the inspector is referring to, is Insulation Baffles, also known as Proper Vents. They are 12" to 24" wide Chutes that are typically 4 feet in length and cost about 2 Bucks per 24" piece, which has a serration down the center, so that it can be snappen in half for more closely spaced rafters than 24" On Center.

The packed insulation along the wall plate of your attic probably is touching the bottom of the attic and also the underside of the wood roof decking.

By being in that position, all of the potential Intake Ventilation from the Soffit Vents are being negated completely.

When installing these New Baffle Vents, you will have created a clear air flow path of at least 1" to 1 1/2" unrestricted air space for the Soffit Intake Ventilation to flow upeards and out of your roof top exhaust ventilation.

Did you REALLY expect the stock personal at any Big Box store to really have any training that would be credible and capable of providing a correct answer?

Ed


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## Scuba_Dave (Jan 16, 2009)

Repeat the Mantra:
LOTS of employees at the Big box stores Do NOT know the 1st thing about anything to with a house 

Rafter vents: allows proper venting
I retrofitted them into my Cape & as soon as I put each piece in I could feel a rush of cooler air coming up from the soffit vent
They DO work


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## Chemist1961 (Dec 13, 2008)

You definately need to create an unobstructed air flow channel from the soffits up to the rooftop and the channel can be easily created with these foam liner products. You also need to retain the insulation above the top plate of your walls and slide these liners over top. There is also a correct ratio of soffit to rooftop ventilation based on roof pitch and vents and surface area. You will generally find a claculation sheet in the BB store shelf where roof vents are displayed
rememeber you will not find and able contractor working in an Big Box Store. I find perhaps 1 in 10 employees I speak to are accurate in their knowledge. A bit of knowledge IS a dangerous thing.
go to www.buildingscience.com


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