Wall assembly remodel advice
I’m looking for advice on how to approach remodeling the exterior walls of my home, both the inside and the outside. I’ll describe what I’m looking for and what I’m thinking, any critiques and alternative ideas are very welcome. I’m not experienced at all in this area but I’m looking to learn.
This is in climate zone 6A.
Apologies in advance for misusing any terminology.
It’s a small single story older home with a vented attic. 2×4 walls with little or no insulation. The sheathing is just horizontal boards with no house wrap with cedar shingles nailed to the boards. There is no flashing or anything near the base of the wall which at times comes quite close to the (very wet) ground. The windows are double pane but without storms or foam insulation. It is on a pier and beam foundation. The interior is mostly old cracked drywall or wood, though the ceilings are ok.
I’m looking for a few main things:
– better sound resistance
– better moisture handling
– increased r value
The sound resistance is very important for me as the house is located quite close to the road which can be very noisy. I’ve read some advice already online and have a few rough ideas about what I’d like to do. The bar is pretty low, but I want to avoid creating new problems (moisture) with the changes.
Exterior
– zip system osb panels to replace the old boards
– cedarbreathe underlayment
– cedar shingles
– flashing at bottom of wall
Interior (option 1)
– screw 2in furring strips onto existing 2×4 studs
– 2×6 rockwool insulation (r21)
– membrain vapor wrap
– 2 layers 5/8th drywall with green glue
– acoustical putty pads behind receptacles
– acoustic caulking around windows and seams
Interior (option 2)
– 2×4 rockpool insulation (r15)
– 1in foil faced polyiso insulation with seams taped (r6)
– 1/2in horizontal furring strips
– 2 layers 5/8in drywall with green glue
– acoustical putty pads behind receptacles
– acoustic caulking around windows and seams
Is there any merit to either option? My worry with option 2 would be that the drywall would be too heavy over the 1/2in furring and 1in foam. I would need to use long drywall screws. This would be for a laundry room, kitchen, dining and bed room. The exterior is the same for a bathroom but I haven’t given thought to the interior.
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Replies
Have you looked into the cost of cedar shingles lately? I was absolutely shocked the last time I had to do a siding repair job and the prices have gone up considerably since then!
If the siding is in good shape, I'd be hesitant to spend the money on the outside and look a little more closely at doing things from the inside as drywall costs haven't skyrocketed like cedar shingles have.
For the interior work, are you familiar with the Bonfig wall?
https://www.finehomebuilding.com/project-guides/insulation/breaking-the-thermal-bridge
There's been a bit of discussion of the technique here too, so worth searching these Q&As too.
Basically it's ripping down strips of 1" EPS foam and 1x3 strapping (or ripped 3/4 plywood) and applying those to each stud to pack out your wall cavity to 2x6 equivalent with the added bonus of a thermal break.
You'd still have to figure out an air sealing method, but the Bonfig keeps your stud bays open so that you can still run electrical conventionally.
You don't need to worry about the drywall falling off the walls as long as the Bonfig portion is nailed well with 3 1/2" ring shank nails. If you overdrive the Bonfig parts, you might have to shim a bit here and there to keep your drywall flat but you'd probably have to do that anyway in an older house.
Forgot to mention on the sound issues... Windows are likely to make a difference here if all you've got is old single pane ones.
Rockwool is a better sound dampener than fiberglass, but addressing any air channels will make a bigger difference to start with.
Thanks! Yes shingles are much pricier than I'd like, but it Is a pretty small building. Having said that I'm very open to alternatives. The siding isn't in great shape, the existing shingles are rough so those will need to go soon, and I figured may as well replace the boards with something more modern while I'm at it.
My plan is to start with the interior then move to the exterior later, but hopefully soon as weather permits. Generally I just want to make sure I have a whole wall plan before starting the interior.