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Insulating attic

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shan2themax

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I was wondering if there was anything else that I could do in order to insulate my attic more (it has plenty of the pink stuff up there) Is there something (like a radiant barrier) that you can apply to the under side of the rafters? or will doint that just cause the wood to detoriate faster?
 

Hube

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an attic (storage type only)should be insulated at least with R 28 (min) insulation.Depending on your location , R 32-40 is even better. The insulation need only be resting on the attics' FLOOR only, NOT in the roofs rafters.VENTILATION of the attic is a MUST, by allowing outside air to enter at the soffit/eaves, and exit at or near the ridge.Make sure the insulation does not block the entry of air at the soffet.
The amount of venting is ;for every 300 sq ft of attic floor area there should be AT LEAST 1 sq ft of venting split between 50 % soffet, 50 % peak.) The more the better.(1 sq ft = 144 sq inches.
Eg; an 900 sq ft attic would require a minimum of 3 sq ft of vent , or 1.5 sq ft of soffit vent and 1.5 sq ft of ridge vent.
A continuous ridge type vent is best, but high, near the peak mushroom type vents are also good.
 

Daryl in Nanoose

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an attic (storage type only)should be insulated at least with R 28 (min) insulation.Depending on your location , R 32-40 is even better. The insulation need only be resting on the attics' FLOOR only, NOT in the roofs rafters.VENTILATION of the attic is a MUST, by allowing outside air to enter at the soffit/eaves, and exit at or near the ridge.Make sure the insulation does not block the entry of air at the soffet.
The amount of venting is ;for every 300 sq ft of attic floor area there should be AT LEAST 1 sq ft of venting split between 50 % soffet, 50 % peak.) The more the better.(1 sq ft = 144 sq inches.
Eg; an 900 sq ft attic would require a minimum of 3 sq ft of vent , or 1.5 sq ft of soffit vent and 1.5 sq ft of ridge vent.
A continuous ridge type vent is best, but high, near the peak mushroom type vents are also good.
what he said:)
 

shan2themax

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so let me ask another question... I will be getting a new roof with a ridge vent only, currently, it has a ridge vent and 3 square whirlygigs (I dont know what they are called), I am pretty sure I saw baffles up there also, but there is no light and I havent gotten brave enough to crawl all the way to the end, it also has two vents on either end of the roof (gable vents I think they are called ) is all of that interefereing with how each system is supposed to work? Once I have the new roof, do zi need to also keep the vents on either end of the house? I just dont want the new roof to develop the problems that this one has if I can help it............

(btw, the attic I would guess to be about 1500 sq ft, the house is 30deep X 50 long)
 

travelover

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Shan2,

First of all, good for you for taking this on. I'd recommend that you Google "attic ventilation". You'll find more than you want to know on the subject.

Basically the way attic ventilation works is that the sun warms your roof (and the air inside), this hotter air rises and leaks out and cooler outside air leaks in, creating ventilation. So you need holes at the top for hot air to escape (ridge vent, gable vents) and holes at the bottom for cooler air to come in (soffit vents). For all practical purposes, you can't have too much ventilation, the issue is usually too little. When you Google, you will find recommendations for how many square feet of venting you need for your total attic square footage. Make these simple calculations to see if you are OK.
 

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