Dear Gwers

Long story, but the contractor has found more lucrative things to do and hasn't completed a bunch of things for us. Case in point A covered and insulated screened porch which we will eventually put in either tile or stone floor. This is above a heated basement space.

The intention was to put in hardibacker before winter and leave the tiling til Spring. Contractor now says that wasn't in contract and he doesn't have to do it. Since I am not happy with his quality, I am ready to find someone else Unfortunately, the existent base is what i would term "particleboard", but he says is "plywood' which is all he is obligated to do.

Is the hardibacker the best solution for protecting this for winter? If we don't do something, it will get wet and swell, destroying the integrity of the base.

What would you do?

Many thanks in advance