Lathe and Plaster Walls

I’ve never seen this before. Old 1890s Folk Victorian. Most of it has some spotty insulation here and there but here under the lathe and plaster is what looks like more plaster in the stud bays. Anyone see this before or know anything about it or have information about it? Just curious.


Where did you take these pics? what wall are we looking at? did you poke it, are you sure it wasn’t some sort of insulation? very difficult to tell what’s going on from the two pics you posted.

Its inside of an exterior facing wall from a 1890s home. You’re looking at some lathe after the plaster has been removed. Inside is not any sort of spray foam, cellulose, etc. Its concrete or plaster or something.

What was on the other side? looks like someone has done updates to the wall/siding/cladding. I’m not sure why you’re inspecting an opened wall, is this part of a home inspection? Basically, if it’s not part of the exterior sheathing/cladding, it is likely insulation of sort.

Again, have you seen this before? I’m not inspecting it for an inspection. Its a rehab I’m working on and in the literally dozens of homes I’ve rehabbed of this vintage I haven’t come across this before. Its again an 1890s folk victorian. Wood horizontal cladding, balloon framed, with wood plank sheathing over the studs. Interior is lathe and plaster. The plater you see in the photo is against the plank sheathing. Simply have not seen this before is all. I understand its likely providing some insulation value and assisting with sealing but I was curious if anyone had any more information on this, simple curiosity.

Sorry, never seen in person, maybe someone else has.

It was common here in California in the early 20th century to not have a vapor barrier on stucco buildings. The theory, as I was taught by Jim Rose of the Plaster Information Bureau was that the permeability of the lime washed (traditional white stucco) finish allowed the wall to breathe, and any water entering the wall cavity met redwood framing and ended up in well ventilated crawlspaces. I can’t remember the last time I encountered an unpainted home of this vintage. I would note the condition on the report and state that current code requires a vapor barrier requirement. Unless door or window are made, this is an as built condition.

Yeah this is wood framed, cladded exterior.