First time post after doing a lot of research and speaking to a lot of folks.

NJ Home on slab on a sloping grade. Back of the house is 6" below grade and front of the house is 4" above grade. No water penetration but there is water vapor naturally due to hydrostatic pressure and porous concrete.

House built in 1960 and probably does NOT have a vapor barrier or insulation under the slab - so it transmits COLD to tile floors and transmits vapor. Pretty high water table in the area.

Trying to address 3 issues

Cold slab - Would like wood for resale value and durability and relative warmth. Would consider engineered floor but my understanding is that they are touch when there is moisture from the ground.

I have a very severe allergy to mold so eliminating moisture, even at a cost increase is worth the peace of mind.

Current Setup - Slab>vapor barrier>2 layers of plywood>hardwood floor (it latest 10 years. Currently it looks like 3 things are going on, 1 plywood has rotted and board are warping (creating soft spots) and cupping.

I was going to do the following to mitigate moisture/cold issue (and yes, it may be overkill but it is peace of mind as well)

Proposed setup - Slab>Seal slab (lithitek 4500/8510)>Dricore R+>Plywood>vapor barrier where directed>hardwood or engineered hardwood.

Not trying to armchair a solution, just trying to take a comprehensive approach to this.

Given my current build there is already close to 2-3" of flooring - the proposed build should be inline with the current.

I am an amateur and would like to opinion of some veteran installers. Rip the above proposal apart - there are not ego or feelings involved. Above is pieced together from a variety of sources (remodelers, techs at Lithitech, Dricore, etc) - All of which have vested interests but also all of whom make decent products.

Once I get the structural stuff in a good place and presuming I can do solid wood, I assume bamboo is my best option (again - mold resistance, hard, etc).

Thanks so much in advance!

-Justin (cold and wet in NJ).

A house on a hill/grade difference will be susceptible to drainage issues. Be sure that you keep water diverted from the uphill side of the house and divert roof run-off. There was probably a layer of pea gravel under the slab when the house was built so the slab will remain relatively dry, but sealing the slab would be the first thing. Vertical grain bamboo may be the best floor, if you want to use bamboo.

Canadian here - for our cold damp basements I would recommend vinyl tiles that look like hardwood. It looks great when installed, is more cost effective and performs better in wet spaces than engineered. Vinyl is also a lot more durable. To get the height you need, dry pack the area.

Regardless what material you choose, make darn sure you have a good dehumidifier attached to your furnace to cycle out the excess moisture that will collect in the basement.

Pete A, we build a patio and retaining wall behind house and we’re diverting much of the surface and subsurface water. I think we have a high water table so I fear a a little dampness.

In terms of sealing it the slab, I am going to use lithitek product (densifies and water proofs).


Weston - this is a first floor, not a basement. There is no basement or crawl space in the house. Just the slab. Vinyl was high on my list but given it is the main floor, I wanted to go to the extra expense to try to make it wood/engineered wood (for resale).

Make sure to divert the water from the downspouts.

Already sealed and routed to a underground drainage system.

I wonder if they nailed the first layer of ply into the slab? All those holes can be bad juju.