How do I install cabinets on a floating hardwood floor?

Question

We just purchased a bunch of cabinets for installation of a bar / kitchenette in the basement. There are 4 wall cabinets and four base cabinets. These are going to be installed on the existing hardwood floating floor, which are sitting on top of a pad and then concrete.

The wall cabinets I can do, I have installed many in the past. But what is the best way to install the base cabinets? Since the floor is floating, I don't know if i should attach them through the floor to the concrete (thus locking the floating floor down i think). Or should I just attach them to the wall and each other and let them float on on the floor? Or perhaps attach to the wall and then glue to the floor with a construction adhesive?

Part of the layout is a peninsula, so two of the base cabinets will only be touching another cabinet and not the walls. If these are not attached to the floor, it seems like these would have the potential to move if pushed or bumped.

I should also note that we will be installing a heavier counter-top, not sure yet if we will do granite, some other natural stone, or stamped concrete. But that might come into play as the weight may hold it down.

Answer 1

Is cutting out the flooring where the cabinets will be not an option? You don't mention it, so maybe there's a reason, but that's the method that would get you the best attachment for your cabinets, while still allowing the flooring to float and move as it's designed. You could make these cuts with a circular saw set to just the right depth.

For the peninsula, I believe cutting out the flooring is your only option. If you try to attach it through the flooring, you're either going to 1) pull it too tight to the flooring so the flooring can't float, or 2) not fasten it tightly enough and it's going to creak and move every time someone leans on the counter.

Answer 2

For the floor cabinets that are not a part of the peninsula- Fixing them to the wall and each other is sufficient. Make sure to either fix them to a stud, or if they have fixed mounting points that don't align with studs, use a 3/16" toggle bolt.

For the peninsula- I'd recommend anchoring them to the floor, or, as you say, they'll be prone to move (And depending on your counter material and peninsula length, possibly cause damage to the counter top). When attaching the peninsula to the floor, do NOT glue them to the floating floor- make sure you anchor to the sub floor. Depending on the layout, It might be a good idea to cut/drill some larger holes in the floating floor, where your anchors will go through. This will allow the floor to expand/contract/slide under the peninsula. (e.g.- drill 1/2" holes, just through the floating floor, where your anchors will go, then put your anchor screw in the middle of this hole, so the floor is free to move).

Answer 3

I contacted the manufacturer of the flooring and this is what they had to say:

Thank you for contacting XXX, I would be glad to help you with your questions. Cabinets are not recommended to be installed over a floating floor, especially cabinets that have a heavy granite counter top. The proper installation would be to install the cabinets and then install the flooring around the cabinets. Installing the cabinets on the flooring could bind the floor due to the weight of the cabinets. If the flooring were to expand due to high humidity levels or other moisture sources the floor could potentially buckle.

So their response was very much in line with the other answers here. The right thing to do in my case is to cut the floor out, and place the cabinets in the cutout.

UPDATE: So I ended up attaching them all to the wall (including just the one side on the peninsula.) Then for the floor, glued felt strips to the bottom of the cabinets, to reduce the friction to allow the floating floor to move more easily underneath them. Now the cabinents do weigh a lot, and we have heavy countertops, so maybe the floor can't move, but it doesn't hurt. Its been about 5 years since I did this, and we've been though many season with humidity, and the floor has not buckled.

Answer 4

There are two concerns here. 1) installing base cabs on a floating floor is never a good idea. 2) since it is a peninsula, I assume there will be a 90 degree angle at the counter tops with a miter joint. Since a floating floor is usually installed over a thin foam pad, there is a bit of give to the floor. This "give" will stress the miter joint of the counter top and potentially cause a gap to open. I would recommend setting all the base cabs unattached, just clamped together, then draw a line on the floor around them and remove the flooring, giving yourself a good 1/4 inch clearance margin. Secure the cabs to a spacer or shims on the floor that are leveled and securely fastened to the subfloor. Trim out and over to the flooring gaps with the kick boards.