Vapor problem with Zip wall?

[shinnlinger]

Hi,  I'm still cooking up a  plan.   Huber just told me I need Kraft faced insulation.  how was I suppose to know that?   
I have a bathroom that I hung rock in but haven't  taped yet.   I plan to pull a sheet and cut thru my poly ISP and see what the pink and inside of the zip look like. 

[Jay C. White Cloud]

Fingered they would some how make it your fault...doesn't surprise me one bit, and I don't think it would have made a bit of difference, maybe even made it worse if you had used craft faced.  Can't wait to see what you find behind that poly ISP.  They are not going to own that there product doesn't work until they have several class action law suites piled up on them, by then they will have made their money and can move on to the next scam...I mean product.  Keep us up to date Dave... ;)

[shinnlinger]

That's the thing.   Zip wall is pretty new.  I was one of the first in my area and now I see it every where.   Most folks probably get there buildings done alot quicker than I do but have no idea that their house is rotting around them.  It's going to be ugly a few years from now!   As much as this sucks,    I'm glad I'm finding out about it while I can do something realitivly cheaply and easily.   

[shinnlinger]

Well I hadn't taped the bathroom yet and we have lived in the house a year so I pulled some drywall, cut thru the foam and pink and fortunately I didn't find any moisture, so it appears that the foam has done a decent job as a vapor barrier.  For the first floor, I think I'm going to insert ABS tubing, random sizes of PVC and conduit I have laying  around and strapping between the zipwall and the insulation into  the stud bays from above wherever I can to create an air space.  For the second floor I will staple attic vent to keep the air movement going and then drill thru the top plates 2 or 3 2" holes per bay into the cold roof.  I will then put 2 layers of poly iso on much lie the second floor and hope for the best knowing I did what I could.  In the spring I will look at drilling in the bottom of the bays form outside and putting screen over the openings....

I looked on Huber's website and nowhere does it say to not use fiberglass insulation.  They recommend cellulose but do not prohibit the pink stuff....

 

[Jay C. White Cloud]

Hi Dave,

That must make you feel better! 8)  That's the bath room so thing's are looking up.    That foam I bet did the trick.  Keep us up to speed.

jay

[Brucer]

Theoretically I'm supposed to have some kind of expertise in this field ??? :.

When I built my house in 1979-1981 I used glass fibre insulation (the pink stuff) with a 6 mil vapour barrier on the inside (building code called for 4 mil at the time). Inner walls are all drywall (aka sheet rock) painted with 2 coats of enamel paint. I stretched the vapour barrier over everything ... electrical boxes, doorways, whatever. Then after the drywall was up I carefully cut out inside the openings so the plastic is actually stretched up tight around anything that penetrates the drywall.

Before doing any insulation, I also used electrical putty to seal every opening in every electrical box on the outside walls. No way for warm air to get into the walls that way.

The outside walls are 5/8" plywood, covered with good old fashioned tar paper.

I have had to penetrate various walls from time to time and I always pulled a sample of the insulation to have a look. Absolutely dry, even now after 30 years.

Keep in mind that the climate here is cool (mostly) and dry. And I don't have air conditioning.

If you seal the interior walls really well, and get obsessive about plugging openings into the interior walls, you will probably be OK in cooler regions.

I've seen a few examples where people didn't get around to finishing an interior wall after insulating it. I've pulled out soggy insulation and even had insulation frozen to the outer sheathing in winter. Looked pretty much like your case.

[tyb525]

I've said it before and again, house wrap holds moisture in. I don't know how many times I've peeled back the housewrap to fix something, only to find rotting OSB sheathing. Housewrap doesn't "cause" moisture, but it does trap it if moisture gets under it. And in many homes, builders don't pay enough attention to making it watertight, or allow for drainage, and that's when water gets under it and can't get out.

One area is windows. They cut the housewrap at the corner of the windows and wrap it inwards, but don't seal that corner where there is now a big gap. Then they don't flash or use window seal around the nailing flange, water gets right through vinyl siding and under the housewrap.

It's a shame builders don't know or care about some of the older building methods used to allow buildings to breathe, thinking it will make the house drafty or something. In fact there is a housing edition nearby that  is being built so bad it should be a crime. Slab houses on top of topsoil, no sill seal under the bottom plate, you can feel the wind blow right through. Asphalt shingles held on with 3 staples. Most of the sheathing is 7/16" foam board, with a few sheets of OSB thrown in for minimal diagonal bracing. The HVAC systems aren't balanced, cold/hot spots all over the house.

And the sad part is, people buying them think they're getting a great spec house.

What happened to some of the old methods, and why aren't they being followed anymore? Some of them were definitely good ideas, and it seems like many of them don't take more time or money to do.

I work for a contractor, he knows "some" old methods but not many, but I'm not about to try to tell him he's doing something wrong ;) It would be interesting to strike out on my own, using more traditional methods.

[shinnlinger]

Well the official word from HUber is once I put the foam up everything will be A-OK and don't worry about, but they dont think it will hurt to vent it either.  So thats what Im going to do. Vent it as best I can and hope for the best.

Dave

[Jay C. White Cloud]

All the luck to you brother...may things go as you plan.   ;D

[tyb525]

What kind of foam are you going to use? Spray on?

[shinnlinger]

I bought a semi load of used poly iso sheets to build my roof "sips" but had enough left over to do my walls also.  2 layers over the inside face of the studs.  Should be a good vapor barrier if I can seal it to the floor and ceiling.  IN my bathroom pic you can see what I did downstairs.  Only one layer there, but same idea.