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Breaking the Keys & Leaving the Mess

Removing the plaster and lath in our dining room continues. I’m doing most of the plaster removal and cleanup while Hubby removes the lath and some of the harder-to-remove plaster.

Back in the early 2000s, when we were remodeling other rooms in the house and removing the plaster and lath, I learned one trick that could help remove the plaster more easily: Breaking the keys.

That sounds mysterious, like snapping a bunch of skeleton keys in half. It’s actually more mundane, though still interesting.

When wet plaster is applied to lath, some of it squishes through the cracks between each piece of lath and laps over, causing the plaster to hang onto the lath. This plaster that laps over and dries in place is the key.

Plaster peeled back from lath. When applied, plaster seeps into cracks between the lath. When dry, this creates a "key" that locks the plaster onto the wall. April 2022.
Plaster peeled back from lath. When applied, plaster seeps into cracks between the lath. When dry, this creates a “key” that locks the plaster onto the wall. April 2022.

This is a remarkably sturdy method of creating a finished wall. It can be difficult to remove plaster because of the strength of those keys. To more easily remove the plaster, you have to break the keys.

I attempt to do so by randomly pounding a hammer on the wall where I want to remove the plaster.

Pock marks in plaster caused by a hammer. Pounding on the wall helps to break some of the keys holding the plaster on. April 2022.
Pock marks in plaster caused by a hammer. Pounding on the wall helps to break some of the keys holding the plaster on. April 2022.

Aside from helping the process, it’s a remarkably satisfying way to work out your aggressions.

When I first got started with plaster removal in the dining room, I was trying to prevent a giant mess by grabbing pieces of plaster as I removed them and throwing them into a box. After realizing how time consuming this process was and that I could not catch every piece as it came off the wall, I abandoned my desire for tidiness and let much of the plaster fall to the floor on its own, leaving the mess behind.

A pile of broken plaster on the floor beneath the wall. April 2022.
A pile of broken plaster on the floor beneath the wall. April 2022.

That sped things up considerably. I’d clean up the mess once I had finished a section of wall. That not only kept the mess to a minimum and prevented us from stepping on a lot of plaster chunks, it also allowed me to change positions in the process. I could go from pounding and chipping plaster with a hammer and crowbar to filling a box and bucket with plaster and taking them out to the construction dumpster. Because the plaster is so heavy, I can only partially fill the box and bucket I’m using.

This is hard work that my body is not accustomed to, plus I don’t have the strength or dexterity I used to have. After spending 2-3 hours on plaster removal and cleanup, I wake with very sore shoulder and neck muscles and stiff fingers. I don’t know how construction workers manage this sort of work every day.

A wide-angle shot of the east dining room wall with the plaster and some of the lath removed. You can see a bit of my husband removing lath off to the right of the photo. April 2022.
A wide-angle shot of the east dining room wall with the plaster and some of the lath removed. You can see a bit of my husband removing lath off to the right of the photo. April 2022.
The north dining room wall with most of the plaster and some of the lath removed. Note that the chimney on the right of the photo is still covered in plaster. April 2022.
The north dining room wall with most of the plaster and some of the lath removed. Note that the chimney on the right of the photo is still covered in plaster. April 2022.

Hubby and I are pacing ourselves with this project, limiting ourselves to one wall a day. We’ve got one wall where we’ve completely removed the plaster and lath and another, the north wall with the chimney pictured above where we have some lath left, plus the plaster on the chimney to chip off. There are no keys to break on the chimney, so plaster removal is going to be tedious on this.

We are not looking forward to removing the plaster and lath from the ceiling.

Thoughtful comments welcome.