How to deepen a 2.5″ thick exterior wall stud with no rim joist?
mateohao
| Posted in General Questions on
Hello all, I was removing my chimney when I discovered my house is framed with 2×3 studs and without rim joists.
I have plans for stripping the siding (I have no exterior sheathing) and insulating the wall cavity with cellulose (zone 3C), but I’m not sure how to also address the skimpy construction.
I thought to attach a full rim joist around the house, then use it as a ledger for a second 2×3 stud wall to make a 2×6 deep wall. I’m not sure what method would be best to sister these two walls. What do you guys think?
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Replies
Hi Mateo,
Are you sure the studs are not standard, nominal 2x4s? The actual size of modern lumber is smaller than the nominal size. For example, 2x4s are actually 1.5x3.5 inches. Given the lack of rim joists and sheathing, that is probably not the case here. But I wanted to make sure.
Also...
Is this area one or two stories?
Hi Steve,
The studs are 1.5" x 2.5". The house is one story tall.
It's over 100 years old, so at least the studs are made from nice Douglas Fir. I should just turn it into furniture.
I have to ask what you are really saving from the original after you change the siding?
If they cut enough corners to use 2x3 lumber my guess is every other corner was cut. You seem likely to have the cheapest leakiest windows imaginable will you install new siding around crappy windows? By the time you pull the old siding off the flimsy 2x3s and hammer on sheathing and siding it seems very likely every nail in the drywall will have popped out and need to be reset and mudded. Without a rim joist the floor sound like a mess. I am guessing the roof is not any better.
I am guessing that the roof has no overhang so making the wall thicker to the outside will be very hard work.
Will you build a new bigger roof to cover your new walls around your new windows and siding and fresh drywall?
From a dollars and cents point of view the smart move is to paint the house and sell it. If you are attached to this bit of land the smart move is to push the shack over and dig a new foundation. It seems like the amount of expense and effort needed to make it right will cost more than a new build.
Walta
Hello Walta,
The roof has an overhang, and is of modern plywood and asphalt shingle over the original skip sheathing. There is some room for a thicker wall.
I would love to turn the house around for sale but most of the housing left where I live is like this. I'm trying to do what I can to keep it from falling apart, because I will never be able to afford to move back here.
Hi, Walter. May I ask you about your appinion in my new question? Thank you
https://www.greenbuildingadvisor.com/question/new-construction-with-the-premium-builder?discussion=edit
Walta does have some good points, with the amount of work you are looking at, rebuilding is comperable.
A couple of pictures can help to figure out what is possible.
In warm climates, most of your HVAC load is cooling. Wall insulation doesn't matter as much for that, more important detail to get right is air sealing. Even something as low as an R5 wall would get you most of your cooling energy savings. It might not be worthwhile fixing the structure.
Hello Akos,
I am just trying to improve the living comfort because I can't afford to move or build new, what with the economy being destroyed again. What photos would you like to see?
If I want to improve air sealing, it will have to be at the drywall and finished floor. I would have to pull out the window casing to access the window flanges, yes? They are some kind of aluminum retrofit from 30 years ago.
If you are residing, the best way to air seal is to tape the seams on the new sheathing. You should not have to pull out windows, you can do a decent job there with canned foam from the outside.
It definitely is tempting to increase the stud depth while the wall is open, just not sure if you'll get much return on energy savings.
If you want higher R value, I would look at going with Zip R for sheathing or a layer of rigid insulation over the new sheathing. Even 1" of poyiso would double the R value of your assembly and is less work than reframing. With the current cost of lumber, the layer of rigid is cheaper.
I would also check local code, ours does not allow 2x3 exterior walls, so you might need to build a 2x4 stud wall beside the current one.
If the old siding is still keeping the water out from an economic point of view it makes no sense to replace it. Replacing the siding is so expensive that it is almost impossible to see a pay back in fuel savings.
Do you have any insulation currently in the walls?
Walta