Working in an old (1920's) house with a stone basement. At some point in the past, it was parged and painted (or somehow colored white). The paint is flaking in some places, and the cement is flaking in others, leaving a sandy mess on the floor.

I'm not quite ready to re-parge the entire basement, but I would like to start with some of the worst areas.

Where it's down to the stone, I figure I'll clean out as much of the old mortar/sand as possible and use mortar mix to fill and cover it.

Where the stone is still well covered, but the top layer is flaking off, I'm not really sure what to do. I'd like to just put a 1/2" coating of mortar over it, but I'd imagine it may not adhere for very long. I may have to scrape the flaking paint off - but I'm sure its leaded paint, so I don't want to go at it too hard.

I'm not concerned about water. The basement does get damp, but I'm not looking to Drylok it (it sounds like it's not a great idea for stone foundations).

Any suggestions?

 

Eh, I'd go with a pressure washer.


First dig out the sump pump sump by a few inches, since it is usually an earth floor,

that should be easy, it's usually filled with very fine silt. Duct-tape some plastic cling wrap over any electric outlets that are along the wall or within the spray zone.



Raincoat, electric pressure washer, just work your way from the most distant wall clockwise, then again counter-clockwise. Most of the loose wall coatings will be lime-sand or perhaps lime-cement-sand, which should come right off and breakup easily.

 

Thanks Hal. No sump pit there, but may be worth making one to help keep things a bit dryer anyway.

What would you recommend as a coating after the loose stuff comes off? Just a mortar mix?