Hanging Drywall Over Foam!!!

Some folks here seem to have
a burning desire to discuss this subject.
I'll start.
It makes window, doors, electrical boxes
a royal pain int he ass.
It's hard to get screws to recess properly.......


Here you go, discuss away.
Looking forward to at least as many
pages as the thread bitching about it.

what kind of foam are you talking about?

Whatever kind the guy in the now closed
invaluable thread was talking about.
Some kind of rigid pink boards applied
like sheathing on the interior, I suppose.

What's to discuss? The very guy who made such a fuss over the thing being shut down already pointed out how absurd the idea is.

You tryin' ta start sumthin'?

Shucks Ma'm,
just here to be of service.

Mike - I don't know what is more disturbing about that picture - the two guys in a foam bath or the guy in the leather vest, sailors cap with a glittery mask on...

You shouldn't put foam over warped studs.

2x4 framing bring it up to R-18, Did it in my own home, prior to sheetrock added 4x8sheets of 1/2" foil face rigid foam, Now if i was using my subs to bang out the sheetrock, it might have been a disaster, who wants to use longer screws and pay extra attention to pressing the boards in. I rocked with my own crew, and they did not complain a bit(maybe a little). I am telling you, the rooms are tight, we taped all the seams, i think the overall value is higher than R-18 given the lack of seams between the wall studs and the ins paper, the 1/2' board closes it all up. I also scored the kraft face to avoid condensation. I also set all boxes 1" deep, ext jams on windows, small price to pay for the extra R value. Gmod.

Why wouldn't you just use unfaced batts to begin with? Or were you just using what was already there?

Okay, I'd be the last to say you can't do it, but would you seriously recommend the procedure as a standard technique? I've done a lot of things over the years that pros said couldn't/shouldn't be done, and gotten away with them. But that was for myself, on my own dime--and willing to deal with the consequences if it didn't work out.

On a competitively bid job for a paying customer, no way would I go that route.

Tested in my own home, jury is still out as to whether i would try it with a customer, the only concern i have is screw pops over time due to scew length and compression variable. As far as the unfaced, during the brainstorming i was talking to many different people, Ins and energy experts. my insulating company etc'', I was getting different takes on the vapor barrier, i installed kraft, then reconsidered, and simply scored the face. I have always used my own as lab for construction techniques in order to learn and push the limits. Some things i later applied in the field, some things i kept for myself, GMOD

I've sandwiched foam over existing drywall with fresh drywall on top.

No call backs-good sound deadening on 'party walls' in town houses.

Glad I didn't know it was supposed to be difficult,just another day.

SOT!
The original OP was dealing with
exterior walls.
Moving entry door jambs, extension
jambs and sills on windows, box extenders.......

With higher insulation ratings being desired or required this is going to be an ongoing issue, not only with hanging drywall on the inside of structures but attaching exterior board surfaces with rigid foam on the outside of structures also. It hasn't come up yet in our designing but I know it will and have some concerns about it.

One of my concerns is that since foam really has no density to it is there going to be a problem with long term deflection due to gravity pulling down on the drywall which is being held by longer screws that aren't being fully supported when passing through the foam. Does anyone have any insight on this concern?

Thanks for any input.

I have done this in my own house as well as others, typically on capes where there are sloped ceilings and kneewalls. Those kneewalls leak air like crazy and the thrermal break the foam provides vastly improves comfort and eliminates drafts. The 2 x 8 rafters you typically see on these home also can only support R-19 insulation if you want to maintain venting from the soffit to the attic, so the foam helps boost the r value. I have always used Tuff-R foil faced for this and unfaced fiberglass batts. 4 years in and no issues with screw pops in my own home.

Funniest thing iv heard all day

The probelm with foam, is that no one wants to pay the extra to have the job done right....the extra time......and the pain in the ass factor.....it may be a great product, for the home owner, but here in pg, when we get foam block ext. walls in the basement, I add in 5cents a foot for the basement.
If the holding tabs are not lined up it is a real headache, and most times when we encounter foam ext. walls its a DYI contractor who knows very little about drywall and our needs.

Don't use screws, use liquid nails in excessive amounts. It works great.

you could use furring strip. insulation between. or in commercial work z furring