Free floating hardwood floor
When I bought my o3 Alpine last November, I noticed slight separation of the engineered hardwood floor panels. I had plenty of other stuff to repair so I left it for a later date. After a few months of use, I noticed that the end panels (the ends that butt together) had separation as well. I started to research the situation, and the consensus was that the wood contracts and expands. I did not believe this to be the case, since I have used engineered wood flooring in homes in the past and have not had this issue, (or at least not to this extent). Some of the gaps at the end boards equaled a good 1/8 of an inch. The flooring in my dp is tongue and groove, laid free floating without any adhesive or attachment to the sub-floor. . I checked at the carpet edge of the floor, and sure enough, the boards were sliding laterally until they hit the carpet tack strip, creating the gaps in the butt ends. My dilemma was that this floor still needs to be able to accommodate slight expansion and contraction and still be somewhat free floating, without creating these gaps.
clean floor with non wax cleaner and let dry over night.
1. Run a bead of good quality wood glue into butt end gaps. Do this one board run at a time.
2. Place a broad chisel at the carpet end of the board run. Hold the chisel pointing straight up, and whack the metal side of the chisel with a hammer. You are trying to scoot the wood boards along to take up the gaps in the butt ends. Wipe up the excess glue that squeezes to the top. Do the entire floor and let the glue dry over nite.
3. Go to your favorite hardware store, and get 1 tube of "big stretch" calking in the appropriate color to match your floor (Ace carries it). Too light is better than too dark on a light floor.
4. Squeeze some calking on the back front edge of a 1-1 1/2" inch putty knife. Fill the slight remaining gaps in your floor at a 45 degree angle with a downward pressure on your putty knife. You want to really get it in there. Scrape off excess calk and clean off with a well wrung out wet sponge. Make sure the sponge is not to wet, or it will wash out your calk. I used a sponge with the green scrub pad on the back. Worked well. Do this process one board run at a time, so the calk doesn't set up on you before you can clean it.
5. When you are all done, clean the floor with a moist green pad in the direction of the grain on your floor, follow with a damp sponge.
DO NOT USE WOOD FILLER IN PLACE OF "BIG STRETCH". IT DRIES RIGID AND WILL BREAK OUT IN SHORT ORDER.
I did this process a month ago, and it looks great. It will still allow very slight movement without creating cracks. In a stored motorhome, we have much wider temperature swings and obviously more movement than in a house, so household methods do not work.
Wear Knee Pads!