I’m building a new house this summer which I’d like to insulate well. I’m leaning towards 2×6, 2 ft. o.c. for the walls with 3/4″ of rigid foam over the studs on the interior. I then plan to screw on 5/8″ drywall throught the foam. For base and case, I then have 1 3/8″ of drywall and foam to go through before hitting wood. If I use 1/2″ thick trim and 2 1/2″ nails and can countersink them 1/8″, then I get 3/4″ of penetration into the wood. Does this sound okay? Are there any other problems associated with such a large gap to span between the trim and studs? Thanks for any help.
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I don't see a problem. It's not like you are asking the finish nail to span a gap. The nails just really keep the trim from falling under it's own weight.
If you are still concerned......run a bead of yellow glue on the back....or liquid nail for moldings higher up.
Just cut and fit it tight....practically holds it's self up with no nails or glue! Lotta times I'll cut and fit all the base in a room and go back after and gun it all in. Even a long run of crown can be tacked with just a few nails...then nailed off all at once.
Have fun, Jeff
* Jeff J. Buck/ Buck Construction/ Pittsburgh, PA *
2nd Generation Buck Const, 3rd generation Craftsman
These are just exterior walls, right? If you want, how about 16penny finish nails?, the interior walls 2x4, 1/2 rock both sides right? Get some long screws for those kit. cabinets. Or put the foam on the other side of the wall.
Edited 4/2/2002 6:55:02 PM ET by panama red
Edited 4/2/2002 6:57:07 PM ET by panama red
Nope, the foam definitely belongs on the inside or you cause condensation problems.
Excellence is its own reward!
Do it and I bet you will be able to knock the base loose with a good door slam. 1 3/8" of soft material won't provide lateral support for the nails and while 3/4" penetration is enough to hold the trim while glue sets it's not enough to suc k the base into the wall at corners and butt joints or any other wall imperfection. Use glue and the next guy to work on the place when the trim has to come off will be cursing you (and it sounds like that would be you).
I'd suggest hand nailing the base with three inch minimum. Predrilling will make it cleaner.
Dick, you must not be aware that the fine homebuilders don't want to sink a nail into wood more than 1/2", ( I heard it is all you need and anything more wears out your nailgun). Also, you don't need to shim doors, lol.
I'd provide links to the facts but...I don't know where anything is anymore.
Anyhow, stop letting reality wear you down.
Oh jeeez, I must have slept through that class.
the no-shim doors guy was Gary Katz. How did I know that would come up???
Frame you walls right...and the trim will stay put......just don't let these guys go around slamming doors while the glue sets. Jeff * Jeff J. Buck/ Buck Construction/ Pittsburgh, PA *
2nd Generation Buck Const, 3rd generation Craftsman
Up here in Canada we put the ridged insullation on the outside. In trade school they taught us to do that because of off gasing & in case of fire. The ridgid stuffs a real killer when it burns or even melts which is very possible with the heat that goes through a burning house.
I know with 5/8 drywall theres less chance but would you bet your family's life on it?
Just a thought.
Ted
Jeff,
I do see a problem with drywalling directly over the foam. Here's what's going to happen...
When you drywall directly over the foam, some of the screw heads will hold very well, they won't fracture the gypsum core on initial screwing, and they will, as silly as this sounds, "over suck" the drywall onto the foam. What I'm saying is that they'll slightly compress the foam and snug the drywall tight to that depression in the foam.
An hour...a day...a week...maybe when getting jarred from the trim install...the gypsum core fractures from holding that over-tightened screwhead in. The drywall screw head pops through the gypsum as the the drywall releases away from the foam.
With the screwheads holding "differently", you can also get a somewhat wavey look in the face of the drywall.
So...furr it out.
After hanging the foam, run furring strips horizintally across the wall about every 16" oc. Furr around your windows and doors so you can nail your trim into the furring. Screw the furring through the foam and into the studs. Install a run of furring "blocking" where at a height you may want to later add a run of picture rail molding, etc...plan now to minimize stud-hunting later.
Furring adds little expense in terms of labor and materials to an interior-clad RFBI wall, but gives a superior end product.