Loose Laminate Plank Problem

Q: I have another situation with a new laminate floating floor that was also just put in my home. The last plank which is up to a door way with tile in the next room, pushes down when stepping on it. Someone suggested gluing that plank to the concrete subfloor. Do you know if that could cause problems with the other planks attached to it, and if so what could it cause. Would that present a problem with expansion?
Any other suggested solutions?
Also, wondering if it is ok to glue a transition strip to the top of the laminate, or can that cause any problems with expansion of the floor?
Thanks. John
A: Toward the edge of any given floating floor you are a bit more likely to feel movement, but this usually only occurs when part of the subfloor is uneven or if rather heavy furniture is place on another area which is causing the floor to tilt slightly. Usually the movement your are experiencing occurs when a small valley is present in the subfloor that was not leveled out. To resolve this you will want to remove a few rows at the edge of the floor, map out where this valley is happening and apply a self leveling compound.
Now if you know for sure that the subfloor was level when the floor was installed and there is not any excessively heavy furniture on one end of the floor then you might want to look into what underlayment you have under the floor. Some underlayments which are less dense than the premium underlayments will put a bit more spring into a floor, especially at the edges. If you are using an underlayment like Cork or Sound 6 this should not be an issue, but if you are using a combination underlayment or one of the underlayments made by the floor’s manufacturer this could like be your problem. The solution here would be to either add a bit of extra underlayment under the edge of the floor or to put in a similar additional support to help reduce the movement you are getting at the edge of the floor.
I have heard of folks gluing down planks of flooring before, but with a floating floor this can be difficult as you have to account for the underlayment as well. I would suggest avoiding this though, as you can run into expansion issues with part of the floor anchored down and the rest free floating. Your best bet here would be to have the contractor come out, look at the problem itself to determine why it is occurring and what the best solution would be.
As for your trim, you can glue it down to the laminate floor, and I know a few contractors who have done this in the past, but do your best to anchor the transition to the subfloor before being forced to glue this to the flooring itself. This will allow the floor the freely expand/contract underneath the expansion gap of the trim. If absolutely necessary you could glue the trim to the laminate, but make sure your home stays at a constant temperature and moisture level before doing this. If your home’s temperature or relative humidity changes quite a bit throughout the year I would avoid adhering the trim directly to the floor.