# should i ?



## Fix'n it (Mar 12, 2012)

i have some of those, wth are they call, plastic things that staple to the underside of the roof, to prevent the blown insulation from blocking the sofit venting into the attic. 

anyway. were they go from the attic down above the sofit. should i fill the gap ? seems to me, that if i don't, insulation can get down to the sofit = not a good thing ?


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## DangerMouse (Jul 17, 2008)

Yes, you should. I fitted 1" flat foam board to the shape of the baffles and used Great Stuff foam to seal them in. 

DM


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## Fix'n it (Mar 12, 2012)

that is good, but sounds overkill, too me. i was thinking i would stuff some extra fiberglass i have laying around, into the void. that area doesn't need to be air sealed. just blocked off so no blown in can get down there.


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## DangerMouse (Jul 17, 2008)

Not overkill, common sense. It needs to be sealed all the way to the outside edge so the top of the wall is insulated. This was recommended to me by both the guys here, and the building inspector.
There are pics I posted in a thread somewhere here......

DM


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## Windows on Wash (Aug 30, 2011)

The vent chutes you are describing (i.e. polystyrene ones) are for vaulted roof assemblies.










If you have an open attic, you just need the cardboard blockers that are stapled to the sides of the trusses and spray foam them at the bottom side to the top plate. Put some extra foam on the top plate as that area lacks overall R-Value most of the time.


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## Fix'n it (Mar 12, 2012)

yeah, thats what i have. because of spacing i can only use 1 per bay.

what are those cardboard blockers you speak of ? google showed nothing. my bays are very irregular = 16"oc joists, 24"oc rafters. will they work for this ?

i imagine i can use the 3 (6 cut in half) chutes i have ? (since i don't feel like taking them back) i don't see why not.


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## Windows on Wash (Aug 30, 2011)




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## DangerMouse (Jul 17, 2008)

"Accuvent" baffles would have accomplished this as well. I did not find out about them until AFTER I had already purchased my baffles and done most of the foam sealing.... Day late and a dollar short, story of my life.

DM


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## Fix'n it (Mar 12, 2012)

cardboard, huh. seems to me that wouldn't last, dry rot.


mouse. i think i found that thread you speak of, it was started in 2009. 
looked to me that sealing it is not so much the problem. but getting the top plate insulated is a priority. the problem for me is, there isn't much room for insulation. the foam vent touches the sheathing and the top plate at the same time


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## DangerMouse (Jul 17, 2008)

If you mean there ISN'T much room, (typo?) then just get some non-expanding foam for windows and doors and seal away! My concern was bugs as well, which will crawl right through batt.

DM


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## Fix'n it (Mar 12, 2012)

see what i mean. what is a guy to do ?


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## Fix'n it (Mar 12, 2012)

DangerMouse said:


> If you mean there ISN'T much room, (typo?) then just get some non-expanding foam for windows and doors and seal away! My concern was bugs as well, which will crawl right through batt.
> 
> DM


yeah, typo fixed.


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## Windows on Wash (Aug 30, 2011)

Use the baffle you have and SPF the gaps well.

Do you have a froth pak?


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## Fix'n it (Mar 12, 2012)

no froth pak.


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## Gary in WA (Mar 11, 2009)

Foam board/canned foam the wall cavity --in the top 4" and air seal as mentioned. Add f.b. vertically on the second top-plate upward. Thermal bridge will be reduced to lower plate only = R-4.38 to exterior. 

Gary


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## Fix'n it (Mar 12, 2012)

GBR in WA said:


> Foam board/canned foam the wall cavity --in the top 4" and air seal as mentioned. Add f.b. vertically on the second top-plate upward. Thermal bridge will be reduced to lower plate only = R-4.38 to exterior.
> 
> Gary


ok, i can do that. 

i foamed one of the chutes with window & door, it took a lot of that. so today o bough some large, over 1", gap filler foam. is this ok ? i don't see why not, but idk.

and on the top plate, that doesn't have a chute, i took some pieces and fitted them horizontally . all the way to the roof sheathing. i was planning on foaming those down to the top plate. then filling the gap up to the roof. is that ok ?


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## Fix'n it (Mar 12, 2012)

in the pic :

left side is the one chute i did.
right side is were i fitted the FB. i was planning on covering that FB with the large gap filler foam. 

then the 4" under the top plate.

ok ?


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## Fix'n it (Mar 12, 2012)

oh. and then, when i do the new siding with FB. i will take off the sofit and foam board up as high as i can on the outside. good plan ? part of the upper wall is above the sofit outside.


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## Gary in WA (Mar 11, 2009)

Appears you are on the right track! Keep in mind that continuous (to vent* every* cavity) soffit venting is best, located as close to the fascia board as possible for best wind entrance and pressures. With f.b. outside, the cavity foam may be redundant. Depends on cost/location R-value requirements.

Gary


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## Fix'n it (Mar 12, 2012)

GBR in WA said:


> Appears you are on the right track! Keep in mind that continuous (to vent* every* cavity) soffit venting is best, located as close to the fascia board as possible for best wind entrance and pressures. With f.b. outside, the cavity foam may be redundant. Depends on cost/location R-value requirements.
> 
> Gary


THANX, again, Gary :thumbup:

i cannot, for various reasons, vent every cavity. but it will vent every one i can. i expect this will end up being about 60% of them. even this will be TONS better than what was there, so i feel confident with it.


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