What are the best repair options for addressing the large gap between the outside wall and adjoining stud wall in this old house with historical movement?
Asked by Maxine Ortiz 
2 months ago
Last Updated: July 26, 2024
So, I’ve taken off the wallpaper and now I’m noticing a pretty big gap where the outside wall meets the stud wall next to it. Looks like someone tried to fix it before, but I’m not sure what to do next. I know this house has had some movement over the years, but it just needs some repairs. What would you suggest I do?
If you’re moving often, consider taking the entire seam with you. You might want to look into a highly elastic product such as CT1, which is paintable and can cover larger gaps.
To repair the entire seam, cut it, apply joint compound, and sand it down.
Hey Crystal Dawn Stewart, consider using mesh sheetrock tape for extra reinforcement
Crystal Dawn Stewart, I need to go 2 inches deep before I find something to bond onto
Hey Crystal Dawn Stewart, remember the tape is meant to help, make sure to lather up the edges well
This type of tool can help you achieve a perfect 45-degree inner corner angle with the sheetrock mud. Just apply the mud to the pointed part and as you push it into the corner, the mud will spread out to the edges. If the mud extends beyond the corner blade, use a 4″ flat blade to smooth it down to avoid excessive sanding. You can find helpful how-to videos on YouTube to further explain how to use a corner tool. Hopefully, you can find a more affordable option than the specific one mentioned.
Old house, how ancient is it? I’m guessing these walls are made of plaster and back lath. You should stick to using plaster to fix this, joint compound for drywall won’t work. You need genuine Plaster of Paris. Make sure to carefully read all the instructions before mixing the plaster. Get rid of anything that’s loose and ensure the surface is clean. Add a binder when mixing the plaster. You’ll have to work quickly, this type of plaster dries very rapidly and is tough to sand, so being precise is important. Be sure to tightly pack the plaster into the hole to create a key. The key is a blob of plaster on the back that will fold over and when dry, it locks the new plaster with the old. Once it’s fully set and cured, you can use hot mud 45 to correct any flaws in your plastering. Add a bit of binder to the hot mud as well. Hot mud 45 gives you around 45 minutes to work with it, but in reality, it’s more like 20 to 30 minutes of working time to smooth out high, low spots, and eliminate any tool marks. Return the next day, once it’s completely cured. Sand it down smoothly and apply a primer. You should be all set to wallpaper then. Best of luck.
Thanks ! It’s lucky that I have some very old plasterboard from the 1930s because I’m not very good at plastering.
Start with expanding foam and then use regular filler
Get rid of the caulk from the entire corner. Fill in a metal-backed paper-faced inside corner bead with mud. Finish it off with another layer of mud (drywall compound.) Lightly sand it and apply primer. Now you’re prepared for your wallpaper.
I want to thank everyone for their advice, I really appreciate it. I feel more confident now about tackling this myself. Earlier, I was panicking, worrying that whatever I used to fill the gap would just sink in.
Suggests using foam backer rod or filling it with green lid (general purpose joint compound), then applying paper tape, feathering the edges, sanding, and priming. The drywall will absorb the adhesive and prevent the paper from falling.
I would recommend avoiding the use of any premix joint compound in this particular situation. They tend to be a bit soft and can shrink. They are not designed to fill a gap of this size. Instead, use Durabond from the brown bag, not the easy-sand version. Make sure to mix it thick, apply tape or pre-made corner attachments after filling the gap, smooth out any excess. Allow it to harden before applying a thin layer, feathering out 6 inches. Finish up by touching up with regular joint compound.
Step one involves expanding foam. Step two requires plaster of Paris and fiberglass. Step three entails finding a coat of plaster.