Altered Surfaces

On the initial visit I noticed efflorescence (moisture pushing salts through concrete) on the foundation wall, and commented how you probably had MVT (moisture vapor transmission) on the wall and could also be in the floor. You were adamant that was impossible because the sump pump has never run and is dry as a bone. I mentioned that MVT doesn't always mean water and I can't warranty MVT and is in my contract, you again were adamant there can't be any moisture, sump pump is dry. After staining and rinsing the floor the next day I noticed spots crystallization on the floor, it grew almost an inch high (I have never seen that happen in 17 yrs of staining) I brought it to the attention of your husband. While I was grouting your control joints he researched it and agreed it was probably efflorescence but said to proceed with sealing and will keep an eye on it. you contacted me a couple months later stating the polyurethane was bubbling, I believe I mentioned then it was probably MVT but would come out and take a look. When I came out I had mentioned MVT again and you showed me a book of pictures you took when the home was under construction. In that book we both saw the concrete contractor missed a section of vapor barrier under the concrete and that is where the MVT is probably originating from and since I use I high solid Polyurethane it seals the concrete and the MVT is most likely spreading as it builds pressure. There is only one reason a coating will blister/bubble after it has cured, pressure from below. The new sealer that was used by the other company is probably a less solid sealer (water based concrete sealer?) and less likely to blister. I believe in longevity and low cost. In 17 yrs of doing this type of work you are probably the 6th person to have this problem and that is why I put it into my contracts, I do not have X-ray vision and look through your concrete I can only educate my clients, it is up to them to listen