Adding insul. behind drywall. Options?

[Mike R]

Any suggestions on adding insulation behind existing drywall? There is currently R13 inbetwen the studs, but because it was in an old rehabbed house, there are alot of gaps and air leaks. Is open cell foam even an option or other blown in insulation? Any DIY options? Appreciate any help that you have to offer. Thanks!

[hausdok]

Hi,

That will be very very difficult to do if there's already insulation between the studs, unless you're willing to open up the walls, remove the insulation shoot the wall with closed cell to minimize air drafts. You could always add a layer of Wallmate (Google Wallmate and Dow) on the inside and a second layer of drywall but you'd have to be careful not to create a wrong side air barrier in the wall. Alternatively, you could add a sealed layer of closed cell over the exterior, fur it out and then add a rainscreen wall outboard of that. Both methods are a lot of work but the former is probably a lot cheaper.

ONE TEAM - ONE FIGHT!!!

Mike

[Bill Kibbel]

Both methods are a lot of work but the former is probably a lot cheaper.

Either method is likely a >20 year return on investment.

[hausdok]

Originally posted by inspecthistoric

Both methods are a lot of work but the former is probably a lot cheaper.

Either method is likely a >20 year return on investment.

No doubt. Sweaters work a lot more quickly and they're cheap.

OT - OF!!!

M.

[Steven Hockstein]

In case you have not tried these, a few simple things that help reduce drafts are to make sure that all windows and doors close and seal tightly, add gaskets at electric boxes, add insulation along rim joists in the basement.

[kurt]

What Steven said is very true. Tighten the envelope first. Then think insulation. That was always our mantra in the 70's.

UFFI actually workded wonderfully for retrofit. I've never found any other material that filled the wall cavities satisfactorily.

[jimmy]

retro fit is what you need foam in insulation i do the job your talking about every day we drill a 2 inch hole outside under siding and fill it with foam we also do brick

[hausdok]

Hi James,

There's already R12 in these walls. Won't that interfere with the foam when you try to fill the wall cavity?

ONE TEAM - ONE FIGHT!!!

Mike

[msteger]

Any suggestions on adding insulation behind existing drywall? There is currently R13 inbetwen the studs, but because it was in an old rehabbed house, there are alot of gaps and air leaks. Is open cell foam even an option or other blown in insulation? Any DIY options? Appreciate any help that you have to offer. Thanks!

Pull the cover plates off the wall receptacles, cable and phone jack boxes, etc. Spray some expandable foam in the rear holes (normally 4) where wiring does or can pass through. Since these boxes make the wall insulation at this point be very low, especially at a west wall, sealing these up can make a difference, and even adding some of those foam receptacle covers behind the cover plates.

[Jeff Beck]

Mike,

Don't forget the rim joist.

I'd consider sealing the rim joist or band board and then forcing 2" foam board into the joist bays.

While you're at it, seal the intersection of the mud sill and the foundation top.

Your floors will feel warmer, there will be less drafts and the walls may even feel warmer.

Jeff Beck

Foresight Home Inspection LLC

[Vicbowling]

That would be a good option because it would be an easier solution than messing with the drywall and now you can even get a green product that shouldn't be too noxious to deal with. "Foam-it Green" spray foam insulation could work as a solution and not be as irritating as pink insulation.

retro fit is what you need foam in insulation i do the job your talking about every day we drill a 2 inch hole outside under siding and fill it with foam we also do brick

[RSpermo]

There are many companies in the weatherization business that are having success by blowing cellulose into the wall cavities from the exterior. I have seen it done in 40 - 50 year old houses. By the way while you may have R-13 insulation in the walls your wall is probably closer to R-8.