Basement Brick: Remove White Stains
LESLIE: Alright, we’re going to talk to Ann who’s got a powdery substance on some bricks in the basement. What can we do for you?
ANN: I have this powdery, which is a mortar, between the bricks. And I was wondering what the solution was for this?
LESLIE: Are you seeing like a white dusting on the bricks or are you talking about …
LESLIE: OK, so the mortar’s not like crumbling out; the grout’s not coming out?
ANN: In some places, yes.
TOM: OK. Well, it sounds like you have two issues. The white, crusty stuff is mineral salt deposits and what happens is when you have water that gets into the foundation wall it leaks through because the block or the brick is very hydroscopic; it’s very absorbative and the water gets pulled through. And then it gets to the other side and evaporates to the air but it leaves its mineral salts behind. So you’re looking at different mineral salt deposits on the wall. They’re not structural. They’re not going to hurt the wall. You know, you can remove them with a vinegar and water solution.
The second thing is when you have deteriorated mortar that’s very typical in a very old brick wall and sometimes that has to be repointed. That’s a basic masonry repair that could be done by a mason. Typically they mix up some mortar; generally make it a little stickier than it would have been the first time it went in. Scrape out the old stuff and then repoint those joints with new mortar and that’s the way you maintain a masonry wall.
ANN: Isn’t that a long and tedious way (INAUDIBLE)?
TOM: Yeah. Yeah, welcome to home ownership. (all chuckle) Sometimes it is. You know, if there’s not a lot of deterioration you may not be able to do the mortar work. But if you’re mostly concerned about that powdery substance …
TOM: … very likely to be mineral salt deposits and nothing to worry about.
ANN: But you don’t think it’ll affect the wall?
ANN: It won’t.
TOM: Nope, nope, nope, nope. Not at all.
ANN: Because it’s in only that one small room in my basement and all the rest are cinder blocks. I …
TOM: (overlapping voices) Yeah, and I bet you – and I bet you, Ann, if you look outside the wall of that area you’re going to find some water sources like an overflowing gutter or grading that’s sloping in or something like that. If you’re always finding it in that one area I bet you there’s a …
ANN: But it’s very dry in my basement. Very, very dry.
TOM: I know that, but I’m telling you it may be dry that your feet are not getting wet but the water is getting against that wall from the outside. So if you look at that area on the outside of your house you’re going to find some adverse drainage condition. I can almost guarantee it because that’s what’s causing those white mineral salt deposits. And that could be easy to fix. That could be as easy as unplugging a gutter.
ANN: It is?
ANN: Oh, well that’s good to know.
TOM: Alright, Ann. Thanks so much for calling us at 888-MONEY-PIT.