How to protect a wood foundation
My house is a walk-in bungalow built into the bottom part of a hill in 1985 approx. and has a wood foundation.
With the high levels of humidity this year, I was concerned about the indoor air quality. Among other measures, a local contractor has commenced excavating around the house, allowing the foundation to dry and is inserting some drainage around the building. The foundation appears to be in good condition. I am also looking into other measures inside the house.
My issue is I’m now getting very conflicting advice on how to proceed moving forward.
1. The contractor has excavated around the house and is installing proper drainage at the base of the foundation. He has also started to wrap the house in thick mill plastic followed by a rap – see photo. So far only the back of the house has been done. Photo attached.
2. A second contractor, one who is working soley on the inside of the house believes that what wrapping the foundation is counter productive and that I should use something like a Sika rolled on membrane to protect the foundation. This contractor is suggesting that moisture will be trapped behind the plastic and that it will be counter productive.
3. A third contractor is also telling me that the thick mill plastic will cause further problems down the road and suggests that I use 2” of spray foam to protect the foundation.
4. A local home inspector suggests that the mill plastic is the correct thing to do and that contractor 2 & 3 are mistaken.
So here I am, terribly confused. I want to ensure that I’m doing the right thing and protecting my house as opposed to doing further damage.
Any insight, suggestions, or comments would be very appreciated.
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