Outbuilding with insulation but no ground vapor barrier – GreenBuildingAdvisor

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?