Outbuilding with insulation but no ground vapor barrier
Hi folks,
I’m doing a reno for a client in Midcoast Maine. There’s an outbuilding on the property, built on PT sleepers. Fully insulated, tight windows, wired with electric.
As soon as I walked in, I could tell there was a moisture issue. I popped off a couple floor boards, dug around and found there was no vapor barrier. Wet dirt under the floorboards. This building is basically a terrarium, sucking up moisture from the ground.
Originally I thought we could just rip up the floor and put poly sheeting down, but as I demo’d today I found some rot around the bottom of the building. Joists and sheathing.
Any thoughts on how to save this building? Or is it a tear down?
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Replies
What are the dimensions and how deep does the ground freeze at this location?
Jack it up and have a series of screw piles driven around it. There are brackets that sit on top of the piles and will hook under the sills. Could also slide steel beams over top of piles/under the building. Probably some digging under the building for some poor soul to have a mid span support, but it could be worse.
Is there enough space to move building aside, scrape away soil, then back fill with stone and a layer of poly? Then move building back; either onto screw piles or dig deep enough to get conc tubes set.
Have similar issues with older garages here that were built direclty on dirt. Usually tearing it down to rebuild is the best option, it really depends on what the building is like.
I have seen them also jacked up and new foundation poured in. Depending on the building, you can raise it with a couple adjustable posts and cast those right into the new foundation.
Since it is hard to dig down with the building above, something like a shallow frost protected foundation is the better option.
Thanks. The building is a small "writer's hut," about 13' x 11'. It could be possibly be jacked up, if not for the giant stone chimney attached to the building. I will know more once we get the framing exposed.