What type of subflooring should I use for a basement?

Question

My basement has wall-to-wall carpet in the two bedrooms and living area. The carpet was probably from the 70's when the house was built and we decided to remove it. After removing the carpet from both of the bedrooms, we noticed some water spots on the drywall and the tack strips for the carpet. It's not currently wet, but I am concerned that dampness will be an issue. We were originally going to put down an organic compound sub-laminate and then have 12" laminate put down on top of that. After noticing the water spots, I did some research and it says if there is potential for moisture, not to put down any material that might be susceptible to mold growth. This included plywood. I was thinking about putting down something like DriCore, but it contains plywood which could rot or mold (if excessive water damage occurs).

So I was hoping to find something that was waterproof. So far I've only come up with a few options, but most of them are not offered locally or for diy's:

• ThermalDry Basement Floor Matting (rigid plastic)
• ThermalDry Basement Floor Tiles (rigid plastic with tile)
• Delta Flooring (Plastic membrane)
• Superseal (Plastic dimpled Membrane)
• Tyroc (Rubber and inorganic surface board)

Does anyone have any recommendations for a breathable subflooring that is waterproof for a below grade basement? Right now I'm leaning toward using Delta Flooring because its a cheap option that I can install myself. Any other advice or experience would be helpful as well.

Answer 1

DriCore is a subflooring that is specifically designed for light or occasional moisture. The portion of the product that touches the floor is all plastic and it lifts the upper portion more than 1/2 inch away from the concrete floor. The joints are fairly tight (although not actually sealed). It is intended to allow water to accumulate in the open spaces under the plastic waffling and drain or seep away without reaching the upper layer.

The particle board that makes up the surface is impregnated with resin and is meant to be fairly impervious to moisture. If you have an actual flood that occurs which is high enough to reach and damage the surface, you have much bigger problems.

Answer 2

If your floor was put down in the 70s and all you can see is some old wet patches with no rot then I wouldn't worry about it, although I'd probably put down carpet rather than laminate as it will breathe and allow any moisture to evaporate. Laminate may expand and wrinkle. Don't break the bank, if 70's ply was good enough until now then 2012 ply will do fine too.