What type of board is this?

[pjkw]

In my house built in 1959, I have boards that I can't identify.
The boards are very similar to plasterboard but are slightly pink; the thickness is about the same as regular plasterboard but they are heavier.
I feel that they hold screws better than plasterboard. The surface has paper like plasterboard, I believe.

Attaching pictures, they look more pink in the pictures than in reality though.

Any idea what these boards are?

 

[Fotografen]

Probably plaster, which is a bit pink?

 

[pjkw]

Probably plaster, which is a bit pinkish?

Yes, maybe it's that simple, was pink popular in the late 50s?
But as I said, it differs in 2 ways, significantly heavier, and better grip when screwing into it compared to plaster.

 

[Fotografen]

I have a faint memory of hearing about some fireproof plaster that can lean towards red-pink?

 

[Stefan1972]

it is probably just some form of outdoor plaster that someone used indoors......

 

[BirgitS]

Yeah maybe it's that simple, was pink popular in the late 50s?

They didn't usually have drywall at all back then.

 

[useless]

Also guessing on outdoor gypsum or fire-resistant gypsum that someone happened to have extra and used there. The panels are not from the 50s.

 

[TypRätt]

There are a couple of threads about pink plaster here, but no one seems to have received a direct answer to the question. However, they seem to be about the same age.
https://www.byggahus.se/forum/threads/aer-det-haer-gipsskivor.464118/
https://www.byggahus.se/forum/threads/vad-aer-detta-foer-skivor-innertak-kaellare.400297/

 

[jonaserik]

It's been a long time now, but I've seen new constructions with a pink board and battens for paneling on several occasions. So it's certainly a type of outdoor gypsum. According to the manufacturer, it shouldn't be covered or installed indoors. Sure, it can be done and it's probably not dangerous. I searched for outdoor gypsum and it emerged that it withstands moisture for several months.

 

[pjkw]

Also guessing it's outdoor gypsum or fire-resistant gypsum that someone happened to have extra and used there. The boards are not from the 50s.

It's been a while now, but I've seen new constructions with a pink board and battens for panels on several occasions. So it's likely a form of outdoor gypsum. According to the manufacturer, it should not be clad or installed indoors. Sure, it works and is probably not dangerous. I looked up outdoor gypsum and found that it withstands moisture for several months

I don't really believe in misused outdoor gypsum, it's more like 30+ townhouses built at the same time, don't know if others have the same boards, but probably, and it seems unlikely that such a large project would use the wrong boards or take something "they had lying around".

 

[jonaserik]

Has anyone in the area opened up an exterior wall, removed the surface layer on it? Normally, these were placed inside the panel as a wind barrier.

 

[Stefan1972]

Don't quite believe in wrongly installed outdoor gypsum, there are probably 30+ townhouses built at the same time, don't know if others have the same boards but probably, and that such a big project would use the wrong boards or take something "they had lying around" feels unlikely

gypsum, as gypsum.....outside it's important which type you take but inside it doesn't matter. It doesn't have to be the whole wall either. Maybe they just needed a piece of gypsum and there was a suitable piece of outdoor gypsum. I can easily imagine that outside, whole boards were used and as little waste as possible. Then possibly cut-offs were used inside to avoid just throwing it away........

 

[tergo]

Then occasionally the cut-off pieces were used indoors to avoid just throwing them away.

when I worked, we were not allowed to use outdoor gypsum indoors, and the outdoor gypsum was normally 9 mm while the indoor gypsum was 13mm
if I remember correctly, the outdoor gypsum came in the late 70s or early 80s