I've taken off some loose plaster in the first 50cm or so above the floor in a downstairs room, on an external wall. The backing plaster has white deposits across it, on its surface - i.e. underneath the skim layer.
The floor here is concrete, by the way - no boards. The skirting boards are twice the height of those seen around the rest of the room and I don't know if the plaster goes down behind them all the way or not.
I don't know about the damp-proofing of the wall in question or how to determine it. I have a picture from another thread of the outside of this wall, and at the bottom you can see the top of what is about 50cm of some kind of render atop the brickwork, going down to ground level. At the base of this wall is a large area of concrete, not soil or anything like that.
http://i.imgur.com/o2F8XO9.jpg
My plan is to fill these holes I've dug out in some crude DIY manner, level with the surrounding plaster and as smooth as I can manage, and then put wallrock lining paper over the top of it all. The whole room could be taken back to brick and replastered if I really wanted to do it properly, but it's not worth the time or money in this case, I feel.
Can anyone suggest the relevance of this white stuff I've found and what it might mean? Could it just be salts from the plaster that long ago surfaced on it, or perhaps something that's "grown" later following damp?
Thanks,
The floor here is concrete, by the way - no boards. The skirting boards are twice the height of those seen around the rest of the room and I don't know if the plaster goes down behind them all the way or not.
I don't know about the damp-proofing of the wall in question or how to determine it. I have a picture from another thread of the outside of this wall, and at the bottom you can see the top of what is about 50cm of some kind of render atop the brickwork, going down to ground level. At the base of this wall is a large area of concrete, not soil or anything like that.
http://i.imgur.com/o2F8XO9.jpg
My plan is to fill these holes I've dug out in some crude DIY manner, level with the surrounding plaster and as smooth as I can manage, and then put wallrock lining paper over the top of it all. The whole room could be taken back to brick and replastered if I really wanted to do it properly, but it's not worth the time or money in this case, I feel.
Can anyone suggest the relevance of this white stuff I've found and what it might mean? Could it just be salts from the plaster that long ago surfaced on it, or perhaps something that's "grown" later following damp?
Thanks,
