We are buying a late 80s vintage house in PA that has strong mold smell in basement and parts of main level of house. The inspector flagged some issues with moisture/humidity in the unfinished basement and suggested we install gutters, improve grading, and contact a waterproofing company about drains/sump/dehumidifier. He believed some combination of those would address the humidity in basement and smell throughout the house. The waterproofing co unsurprisingly suggested a pricey interior drain + sump system. We will start with gutters + grading. The block is sloped quite steeply from front to back so only the front basement+garage wall of the house is underground. With weekend rain, I noticed some dampness in the cinder blocks and in the trench of the floating slabs in the garage+basement along that front wall. Structurally the walls look fine (according to inspector). The house has been grade at the front but it looks like it could use some more. I don’t know why the current didn’t install gutters other than their builder encouraged them not to.
One thing that the current owner pointed out was that he had installed river stone along the front wall of the house as some sort of makeshift drainage system. The ground level slopes down from the front middle of the house to the sides, so it could work in theory. The river stone layer looks about two feet wide and at least a foot deep. I don’t know if they put any sort of waterproof membrane under the stone. The owner places mulch on top of the stone but it looks like it frequent washes away (or seeps into the gaps in the stone) with all the rain that falls from the roof. The drainage system doesn’t seem to be doing its job and if anything seems to encourage the water to stay close to the foundation where it seeps into the cinder blocks.
Any thoughts on this drainage system or on the best way for us to get the basement dry and odor free would be appreciated.