Types of old drywall in homes.

[Slowgsr]

So what I have is basically strips of 1/2 drywall product. Then rather then a plaster over top they apply basically like a concrete parging over the entire wall, they use a metal mesh style inside and outside corner bead. Then they skim with plaster.

Its very strong and very heavy. Overall thickness varies from 5/8 to 7/8.

Does anyone have any more information on this type of stuff?

 

[The Cobbler]

Not sure I totally understand your post, but sounds like you have 3/8 gypsum plaster board with grey rough coat & finish coat on that?

 

[Super Mech]

Do the boards have holes in them? If they do it’s called rock lath.

 

[billie]

One thing to be concerned about, often the compounds from the lath & plaster days and early drywall days used asbestos. I'm pretty sure every state/province has a testing facility.

What you describe, that plaster, was a fabulous, vapour barrier too.

 

[Rock knocker]

It’s called rock lath and was used into the ‘60’s. The GWB was in two foot rippers with a keyway between rips for the plaster.

 

[Slowgsr]

Not sure I totally understand your post, but sounds like you have 3/8 gypsum plaster board with grey rough coat & finish coat on that?

yes that sounds like it.

However there are no holes in the first layer. I wish I would have taken a photo.

My house garage was all that when I gutted it, except no finish coat on top of the grey rough coat.

I did have a small portion of it in my basement when i took out a wall beside the staircase that must have been original to the home.

Here's a photo where you can see the gypsum layer, has evenly spaced dots.

 

[The Cobbler]

its likely 16"x48" plaster board, 3/8 thick with a grey rough coat finished with a white plaster coat . very common in the 50's/60's . very likely to contain asbestos .
yes, very heavy, very strong, very good sound deadening, the grey coat does not like water at all .

 

[Slowgsr]

For some reason I believe I found information on the back of a piece when I took down a small wall and was about to determine the manufacturer and that it didn't contain asbestos. I guess that doesn't set time what was in the brown coat, or the finish coat. I know I had ceiling tiles tested before I pulled them down. Well its down now, and been awhile.

Makes ya wonder all the reno guys who don't bother getting things tested, roofers, that pipe insulation stuff, even just residential guys doing electrical rewires, retrofits, etc. All the unknown exposure to that stuff. Even guys that do removal, at times must be small amounts of exposure.

 

[Slowgsr]

For some reason I believe I found information on the back of a piece when I took down a small wall and was able to determine the manufacturer and that it didn't contain asbestos. I guess that doesn't determine what was in the brown coat, or the finish coat. I know I had ceiling tiles tested before I pulled them down. Well its down now, and been awhile.

Makes ya wonder all the reno guys who don't bother getting things tested, roofers, that pipe insulation stuff, even just residential guys doing electrical rewires, retrofits, etc. All the unknown exposure to that stuff. Even guys that do removal, at times must be small amounts of exposure.

 

[Rock knocker]

For some reason I believe I found information on the back of a piece when I took down a small wall and was able to determine the manufacturer and that it didn't contain asbestos.

That’s really not a fool proof way of doing it. Why don’t you do it the right way.