Frequently Asked Questions

  1. QUESTION:
    hardwood floor over concrete is warped?
    I recently had a hardwood oak floor placed over concrete slab-we had 3/4 inch plywood nailed to the concrete and the hardwood installed over the plywood-it is now warped in several areas-any suggestions for why and how to repair?

    • ANSWER:
      Yes it sounds like a moisture problem.

      Did anyone check the concrete floor for moisture infiltration? You do this by taping a large square (about 18 to 24 inches ) of plastic to the concrete and sealing it all the way around with tape and waiting a few days to see if any moisture accumulates under the plastic.

  2. QUESTION:
    How do I install a closet door track over existing hardwood floor?
    I have down an engineered wood floor. The track for the closet door up top is installed, but not the bottom (against the floor). I am on concrete slab- single storey. Any advice? Should I use a plumb bob from the top track to determine where to install the bottom track?

    • ANSWER:
      Ideally the door should be perpendicular to the floor which a plumb bob or level will give you.
      However, it is more important that the door be parallel to the door opening. If you have adjustment at the top of the door to offset it, you can achieve both, if not go for the parallelism.

      GL>

  3. QUESTION:
    Installing Floating Hardwood Floor Over Concrete?
    We are installing a floating hardwood floor (5″ slabs, 3/4″ thickness) over cement that previously had tile. We’re using a floor scraper to pick up as much of the old mortar and make it as level as possible; however, you can still see the old mortar ridges. Will this impact the install? If so, how do we remove the old mortar entirely?

    Other factors to consider – we’re using 3MM poly sheeting first, then using Elastilon self-adhesive underlayer with the interlocking hardwood.

    Many thanks for your insight.
    Nicole

    • ANSWER:
      It depends on just how many ridges is or isn t there. Some times you can clean and fill in missing spots and smooth coat the whole floor or finish scrapping it down to the cement.
      There are ways to pour a self leveling compound over the whole floor to make it smooth.
      Some times a wide masonry chisel , hand scraper, elbow grease and ben gay will do the trick. Its hard work scrapping it down to be smooth..
      Any questions you can e mail me through my avatar again . GL

  4. QUESTION:
    Recommendations for radiant floor heating over existing concrete slab?
    I live in AZ in an adobe house built in the late ’30s. There is no foundation, just a concrete slab directly on the Arizona dirt. I know heat rises, but it radiates through solid contact quite effectively, and my concern is the earth beneath my slab will absorb some of that heat. What would you recommend as the most cost-effective, sensible solution to heating my 1200sqft house? The roof is not up to modern codes and I hate the idea of sticking a heavy heat pump up there. It can get quite cold at night in Tucson (sometimes mid 20s) but it is RARE that the daytime high is less than 50-something and usually even warmer. Is radiant floor heat even an option on an existing slab? I plan to tile or laminate/hardwood the entire place. How much height will the tubing/elements and thin set add to the floor? Do I need to add a thermal barrier over the slab before installing? I don’t want to add so much height to that floor that I have to redo all my doorways. Thanks for knowing what you’re talking about before answering this question.

    • ANSWER:
      Radiant heat is not a smart way to go…you still need AC and all ducts…so why are you planning on another separate system? Makes little sense. IF you are using wall AC units, then change out for Heat pump AC units in the rooms. IF you are using central air, then add furnace to the duct system…to build a radiant heat system, install a boiler or separate heat pump would be the most expensive way to go…AND you would end up raising the height of the floor at least 3 inches, which means all wood work would have to be redone, all doors changed, and it goes on and on…stick with a furnace and central air…in your climate, the furnace could be installed in a “shed” outside the house. Good luck

  5. QUESTION:
    Engineered Hardwood or Laminate over Concrete?
    I am trying to decide between installing an engineered wood product or laminate over a concrete slab. This would be my living/dining area and would be high traffic. I am also a dancer and would use this floor to practice new moves with my dance partners. I am getting contradictory info from the stores I have visited thus far, and I think they are just telling me things so I will purchase their product. I need help!! I have a few questions: Which is better for my needs? How should they be installed? Can you glue engineered wood directly to concrete without a moisture barrier? What are the general durability-life-spans of a laminate and or engineered hardwood? Will either increase the value of my home? Anything else I should know?
    Thanks in advance!!

    • ANSWER:
      Whatever you decide you need to do a moisture test on the concrete. The wedsite lists several ways to check for moisture. I would try at least one before gluing down any flooring. They do make a wood flooring that can be glued (not sure of the name), we looked into that for our basement, but decided against it because of the moisture issue. Pergo makes a wood laminate that looks real (my mom has this). It is very durable – more so than wood. I think either one for what you are going to be using it for would be great – just get past the moisture test.

  6. QUESTION:
    How to grind a concrete floor for preparation of installing wood and tile flooring?
    Renovating a house. I just realized the concrete slab either has raised concrete or glue/epoxy all over it. I will need to grind this down to make the floor somewhat straight for my hardwood and tile floors. And stupid me just had the whole house painted first.

    Anyone have any suggestions or experiences? Is an angle grinder too small/weak? Is a walk-behind concrete grinder too big or make too much dust? I am definitely not willing to pay someone else an exorbitant amount of money to do something I can do myself for less than 1/10 of the cost.

    My house is about 1500 sq ft. About 800 will need the surface smoothed. I have roughly 10 hours to put into this if need be. I realize I am missing some details (concrete or glue, amount needing grinding, etc), but anything helps. Thanks.
    The self-leveling stuff is a good idea. However, once I level certain areas, wont I need to level the entire house in order to have a transitionless floor? That could be laborious/expensive.

    • ANSWER:
      Rent an electric floor scraper , faster and much less dust. Hope that helps


how to install hardwood floors over concrete slab