holeinsulationplasterwalls
I have a number of ~3" holes in my plaster from where my walls were filled with insulation. (Why did they drill a 3" hole? I have no idea).
Obviously I would like to fill these holes in, but they have no lathing behind them, and I'm not sure what is the best way to fill them in is.
Here is what the holes look like:
Using a 2 1/4 hole saw, cut a plug from some 2x4 lumber. Then use some anchoring epoxy and glue the plug into the hole. Allow 24hr curing. Warm temperatures will speed epoxy curing.
Attach any wood screw to mount monitor bracket.
Heres a no muss/no fuss way to inject the epoxy. You may need to tape across the hole until the epoxy jells. They all mix in the nozzle and harden quite quickly. You use a caulking gun to dispense.
A better question would be, why is my sheathing getting wet?
The grain of the sheathing suggests to me it is Homosote Homasote. It should not be squishy, rather firm and resilent.
Something is allowing water past your brick barrier, and then, past what was vapor barrier (for the time, 15-30# tar embedded felt paper. I would look up, overflowing gutters can get behind fascia boards and run down the inside of the bricks, soaking the sheathing if the vapor barrier was broken during the bricking (as sometimes happened, also mortar bridging can cause this). In no case is it normal for the sheathing to be wet. Poor tuck pointing (especially around windows) can also allow water intrusion.
Once the water intrusion is corrected, all stud bays in the affected areas should be opened and the sheathing evaluated for viability. Also, opening the cavity will allow faster drying out and possibly see where the intrusion is starting.
As an aside, my 1941 house used a gypsum lath board for plaster.
Best Answer
This question is very similar to this question:
How Do I Fix a Hole In Drywall
There are some good answers posted, so it is worth a read.
To build on those answers for this particular case, I would recommend the medium size hole fix. The only difference is since the hole is on the small side, trying to screw the new 3" circular piece may crack or break it in half or in pieces, so my recommendation is to glue it to the strapping or backing material using gorilla glue or similar. Just make sure the new piece doesn't stick out of the existing wall. If you can make it slightly less than the existing wall, that would be optimal, and then you can just fill in the depression with mud/spackle.
If the plaster is painted, you can use mud to fill in, it doesn't have to be plaster as the paint will cover it over. If it is unfinished plaster, then fill in with plaster as the finish will be the same. It looks to be painted, so standard mud/spackle should work out fine.