Concrete Basement Flooring
Q: We currently have carpet in our basement, however during wet weather we detect a musty damp smell. We want to remove the carpet and install a non carpet solution – cork, wood or bamboo – but as flexible as possible. The concrete under the carpet has not been sealed and it not completely level. How and with what products would you suggest that we seal the concrete floor, level it and what would you suggest that we install over it.
Thanks
Jessica
A: It will take a bit of work, but the problem you are encountering can be solved. The musty smell you are encountering is because excessive moisture is coming through the concrete and being absorbed by your carpet. After you remove the old carpet, find the areas of the floor that need to be leveled and all cracks, if any, which need to be repaired. Once you have finished leveling the subfloor and ensured you gave the leveling compound plenty of time to cure, you can then seal the concrete. Do NOT seal the concrete before leveling as this will prevent the primer in the self leveling compound from adhering to the old concrete properly. As far as a sealer goes, RadonSeal is a great product, but any high quality roll-on membrane will suffice.
Once you have finished leveling and sealing the concrete you can now move onto your floor. Your best bet would be to use any floor which can be floated. Floating cork and bamboo will both work well here as would any engineered hardwood which can be floated. When installing the floor you will need to use a moisture barrier even though you have sealed the concrete. Concrete is a moisture based product by nature and even after being sealed, very small amounts of water vapor will come through the concrete (this is normal) and if a barrier is not in place, your floor will absorb this and eventually it will begin to warp. When you install the moisture barrier, make sure you bring the barrier up about 2″ along all of the walls and tape all of the seams. This ensure you have total coverage and there is no risk of moisture vapor coming up through the barrier.
From here underlayment and a floating floor are your choice. Personally I would suggest using a 3mm cork underlayment as it will keep the floor a bit warmer than most foam underlayments and cork makes floating floors walk a bit better due to its density which removes some of the spring you feel with foam underlayment. As far as flooring suggestions are concerned I would suggest looking into Saso or Kahrs for wood floors, Springwood for bamboo and APC or Westhollow for Cork. All of these feature great floating floor lines which are fairly easy to install and have good track records for quality.