this is what im calling barnicles. but my guess is that its alive :)

Hi, Have gutted daughter's room in basement(actually one exterior wall). This wall had efflorescence on it and some of the furring strips had water damage o0n their bottoms near the floor. The moisture problem has been solved(New eavestroughs) and grading away from the house. The problem is that I want to insulate the wall again, and place drywall over top, but the wall is not totally square, i.e. it is not level. I was going to use rigid foam board, and glue it to the concrete, but the bottom part of the wall indents in some places about and inch or so... I guess I can build up a 2X4 wall one inch away from the concrete wall, and then put in batts and a vapor barrier, and then drywall. But I was also considering having polyurethane foam sprayed directly on the wall(about 2"), then building out a 2X3 wall and finishing with vapor barrier and drywall. What would be the better choice and if I were to go with the spray foam, do I build a 2X3 wall one inch away from the concrete, then spray so the spray gets under the 2X3, or do I spray the whole wall 2" thick, then build the wall over it????? I am confused, and hope I didn't confuse anyone....I live in Quebec, north of Montreal. Thank you. George, a proud dad of a U.S. Marine p.s. the reason I was thinking of the spray foam is that it can get into all irregularities, and part of this wall has a closet that has a wierd shaped wall.