Exterior Waterproofing and House with No Footing: okay to do?
I have read many of the awesome posts and posted an earlier question about interior vs exterior waterproofing, etc. Thanks everyone for your guidance!
We have finally started our exterior waterproofing project on our 1920's home in Seattle. Today was day 1 and excavation was done to the level of the basement floor, which is 7 feet below grade.
We discovered that there is no footing at the base of the house. Walls are concrete at 6 inches thick. There are no cracks or breaks in the foundation wall. The original plan was to follow the standard practice of placing the drain pipe adjacent to the footing.
Question #1: Since there is no footing, I'm assuming it is NOT a good idea to install the drain pipe (which will be placed below the level of the basement floor) adjacent to the exterior foundation wall due to risk of destabilizing the foundation wall. Any Opinions on this?
Question #2: I will talk it over with the general manager, but the revised plan calls for placing the drain pipe about 13-14 inches AWAY from the foundation wall and run a delta membrane from the wall to the drain pipe trench. Is this plan going to be as effective as the standard location of the drain pipe?
Question #3: If we proceed with plan B, then will digging a trench below the level of the foundation wall but at 13-14 inches away from the foundation wall cause any destabilization of the foundation wall?
Question #4: Would anyone recommend retrofitting footers to the foundation wall? It is a 2 story, 3000 SF house in Seattle with no visible cracks or bowing of the foundation wall.