CONDENSATION ON WINDOWS

[Bird]

Joe, last night I was trying to remember the name of that stuff. When we lived in a 32' fifth wheel, I used it two winters (the first winter we were back in Dallas for Christmas when we had a record -1 temperature and an ice storm). I sealed all but one window and one roof vent with it. Great stuff, works great, easy to use or install, and cheap to buy. I think I bought it at Sears.

 

[gotrocks]

True story, Years ago when I was in contracting a builder constructed a new home with crawl space on a lot that had excessive moisture. The first winter water would run down the windows and even on down the walls under the window sills. Then they put a layer of polly (maybe it was felt don't remember is poly was available) under the house and covered all the ground area. Problem solved..... well the moisture stopped running down the windows and walls .... but the nail down hardwood oak flooring began to shrink.
I shrank so bad until the flooring had to be removed and reinstalled. Not much fun for the new owners or the builder. As already eluded to above, I believe a house has to "breathe". $ .02 more

Happy New Year !!

 

[heehaw]

very good points, in this area the vapor barrier is very important, but i don't know about other areas; the local lumber co. here has a couple of ex-contractors that moved in from nothern areas, just before we started building our house, and they immediately started telling folks not to put in a vapor barrier. That may have been good information for where they moved from, but not for here.
heehaw

 

[winchman]

Thanks to all that responded! I think the house being tight is the problem. Looks like I need to do a little experimentation to see if I can fix the problem. Does anyone use a humidity monitor in their home? If so, what is a good one to buy?

Thanks Guys,
winchman

 

[beenthere]

That wasn't good information for where they came from either. Some contractors just stick to old ways and putting vapor barriers in were running against their traditional grain. Drywallers don't like a vapor barrier, as it doesn't allow the crack and tape mud to dry as fast, so they would slice through it after the inspector left and before they put up the drywall. Defeated the purpose of the vapor barrier, but accomplished their intent to do the job fast.
Similar, putting a vapor barrier under concrete. Have to wait longer to finish the concrete, as the moisture in the concrete doesn't wick away as fast.
Moisture in a house will condense wherever it gets to the cold. If the vapor barrier keeps it in the house, then it will not condense in the insulation. Anyone can figure it out from there. Dry insulation works, wet insulation doesn't. Wood decays when it is wet. Carpenter ants are an indication of wet wood problems. The carpenter ants won't eat non-decayed, non-wet wood.

 

[DVerbarg]

Hmmm,

<font color=blue>Moisture in a house will condense wherever it gets to the cold</font color=blue>

Don't want to argue but do like to talk an issue through and am willing to play the part of the "poor ignorant soul" in order to facilitate some discussion. Sooo, the vapor barrier on the interior wall will keep the moisture and hence the condensation on the inside -- when its cold outside and warm inside. But what about during the summer when its hot and humid outside and cold inside? The condensation will be on the exterior side of the vapor barrier -- with the insulation in the stud space.

So do we need vapor barrier on the outside and inside? Don't think so as the barriers would create a sandwich which would leak and slowly let moisture in and then very slowly let moisture out -- not too good once the moisture is in there. Or do we look at our climate and decide which season we should install barrier for? Or do we engineer a system that allows moisture to move either way without compromising R-factor or structure integrity?

 

[Knight9]

One guy's opinion:

<A target="_blank" HREF=http://www.buildingscience.com/resources/roofs/ceiling_vapor_barrier.htm>Building Science</A>

Kevin

 

[Joe_W]

Hi Bird,
I just found a package from last year. It's called 3M Indoor Window Insulator Kit. I've used cheaper brands in the past to save a couple of bucks, but the only one I've ever used without any problems is the 3M brand. Better tape, more pliable plastic and when you are done, it's almost invisible.
Joe W.

 

[beenthere]

Thanks for the excellent source of information. One can believe it or not. I think his comments are very good, and the reasoning is good. I will defer any discussion to this source.
Also, his 'ten dumb things to do in the south' indicates maybe the vapor barrier should be on the outside.
Thanks.

 

[Bird]

Yeah, Joe, the 3M is the only one I ever used, and like you said, once you hit it with that hair dryer and it shrinks, it's transparent. Never thought I needed it in the house, but it's wonderful stuff for an RV, and if I didn't have double pane windows in the house, I'd probably be using it here, too.