I thought that attics needed a vapor barrier in contact w/ the conditioned space. My daufghter’s house has none. Zero. Zilch. Nada.
Am I living on the wrong planet?
What to do about it?
Don
Don Reinhard
The Glass Masterworks
“If it scratches, I etch it!”
The Glass Masterworks
“If it scratches, I etch it!”
Replies
depends on your climate really..in the colder regions for sure..There is a paint, I forget the name, but they say that it is comparable to a 6 mil vapor barrier, and it is for just this type of situation..check your paint stores..
All I ever wanted in life was an unfair advantage...
This is in Southern MS. rarely, if ever, gets below freezing, but makes it into the low thirties. Humidity can be near 100% easily. Currently has paint of unknown origin & capability on it.
DonDon Reinhard
The Glass Masterworks
"If it scratches, I etch it!"
man, I live in central alaska and it get's to 50 below zero quite regularly in the winter, so...our vapor barrier is on the warm side always in all situations, no matter what... I hear that in the warm humid areas, if they use one at all, they put it on the ouside to stop that humid air from infiltrating..I'd check with a local inspector..All I ever wanted in life was an unfair advantage...
Considering your climate, you may not worry about it. Your climate is often theoretically the opposite ... vapor barrier on the outside may be more necessary. Someone referenced a good article by Joe Lstibrek (sp) on the topic of vapor retarders, location, etc. ... can't recall ... just saw it the other day (old age gives me a touch of CRS).
For your climate, you don't want a VB on that side.Th e general rule is to place the VB on the warm wet side of the package.Warm and wet for her is outside.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
The Joe Lstiburek article is: http://www.buildingscience.com/documents/digests/bsd-106-understanding-vapor-barriers
One train of thought is to spend some time in the attic airsealing. Spray foam along each side of the top plates of internal walls. But a dollop of foam on wire protrusions,, or use Accoustical sealant on wire pertrusions. Also lay big dollop of foam on ceiling light openings. Most older vapour barrier is improperly installed anyways,, so this is a Huge upgrade with benifits to the heating costs. I think there's a recent FHB article about doing such a thing. It'll work awesome. Spend a good day in the attic and be thorough.
dave
I'd be careful about foaming lighting fixtures that aren't IC rated.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
I'd think it safe to put a dollop on any octogon box in the attic space. I'd think it equally unsafe to have a moisture buildup in said octogon box for lack of airsealing.
I'm in canada, and think my meathods true given my climate.
What's the worry? Overheating 14 guage wires at the entry to an octogon light fixture??
Here in Alaska, it is against codes to have foam touching any light boxes..so what we do(I'm A weatherization Technician) is roll out some normal ordinary tin foil, crush/ cover over the box and about 6 inches around and spray the entirety...works like a charm and it only takes maybe a minute per box...I believe the issue with foam in boxes is it's flamability...but regardless, better safe than sorry.All I ever wanted in life was an unfair advantage...
Hey good one capitan mayhem sounds like a great idea. and yes spray foam in light boxes is a fire hazard, and if there is one thing that I learned as a weatherization crew lead is that tremco in attics is not very effecive. especaly in ones filled with cellulose.
Thanks...We had previously been trying to use visqueen and tremco, or red tape, or a combination of both, to no avail, and one day in a miserably hot attic after about 20 light boxes it dawned on me....I just did the foil technique to a cieling that got fully filled with 4 inches of soy based foam and it worked great, and only took me about 20 seconds a box....after crawling my fat *&s over to them of course...."coldbuilder"?...where abouts are you?All I ever wanted in life was an unfair advantage...
Fairbanks of course, and I think the foil idea is one of the best ideas yet. and if it dosnt catch on than too bad for the non belivers. foil on brotha'"A small leak can sink a great ship."
-Benjamin Franklin-
I dreamt about kicking the #### out of crew 1 last night....does that make me a bad weatherization tech??All I ever wanted in life was an unfair advantage...
not if doing so would reflect well on the homeowners utility bills. nyuk nyuk...."A small leak can sink a great ship."
-Benjamin Franklin-
I suppose one would want to be careful with pots. I usually foam in a drywall box over them.
Agreed; non-IC cans (pots) are the worry. There's no problem with laying insulation over a standard fixture box.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....