Installing Built-Ins Over Carpet

Should built-in cabinets be installed over existing carpet, or should the carpet be cut away and re-attached at the joint? Craftsmen debate the point. July 24, 2005

I often install office desks in rooms with carpet. Of course, the cabinetry is mounted directly to the floorboards. I have to call up a carpet company to re-tack the carpet, or leave the customer with the telephone number. Does anyone do it themselves? Any help is appreciated.

Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor M:
Have you thought about just installing over the existing carpet? It seems like much less of a headache. If the carpet is changed later, the carpet can be cut around the cabinetry and a new tack strip applied at that time.

From contributor R:
I am wondering why you are mounting the cabinetry directly to the floorboards. You may be needlessly punishing yourself to no advantage. In years of work, I've found that carpet often outlasts fixtures for many reasons, so it makes sense to install right on top of it. I too once believed that mushy carpet made a poor support, but after removing many pieces that had served long and well on it I stopped butchering floor coverings.

Shims do work, though some patience is required. If movement is a problem, use angle braces and/or wood block cleats attached to the floor through the carpet. You may already know and fear as I do the horror of unraveled yarn when trying to drill or screw through carpet. One can use a simple grommet hole punch to prepare the carpet for drilling, I keep one with my tools.

Yes, it leaves a damaged carpet, but it's better than the hassle and full footprint of carpet removal, and whatever replaces my piece might cover most of it anyway. Life is a compromise, but you are noy compromising quality by skipping this carpet surgery. It's actually a better job for the client in the long run.

From contributor G:

Im not sure if I agree putting the cabinets directly on the carpet. I would recommend cutting the carpet. From experiences, I have learned that the cabinet will settle into the carpet over time. The key to that last phrase is over time. So that nice crown moulding that you worked so hard to scribe to the ceiling , will in six months time have a nice 1/4 gap. Your customers will be mad, and you will be headed over to their house for your first call back. I would recommend cutting the carpet.

From contributor R:
To contributor G: Was the cabinet you speak of carpet to ceiling, with no connection to a wall? This would be the first I've ever encountered. If it was attached to a wall, what fasteners were used to allow this vertical plunge?

From contributor G:
To contributor R: I have had two instances that had problems, and that was enough. One was floor to ceiling, and one was a base cab set up. The problem is that carpet is not stable and it will give over time. It may in fact give differently front to back (tack strip) or even side to side. If the carpet gives, it doesn't matter what fasteners you use. Either the cabinet or the fasteners will give eventually, that's gravity at its best. I realize it is more work, but in a field where call backs can bury you, I feel it is a necessary step.

From contributor N:
I agree with Contributor G. If I had installed this unit on the carpet I would have been called back by now. The crown meets the ceiling and this customer loaded every shelf with books. As you can see the carpet was peeled back to the bare concrete, and luckily this was in a newly constructed home and there were carpet installers in the neighborhood working. They charged the customer $35 to re-tack and stretch the carpet below.

Click here for full size image

From contributor M:
I've never liked installing over carpeting either. Even if its ok, it just never feels right. I've found a carpet cleaning/repair outfit locally that will cut and reinstall the carpet for about $50-100. They show up next day or same day, and it's well worth the money to have the job done right. There are no call backs, and more importantly no wrecked carpets from me trying to do it.

From the original questioner:
Well, I cut the carpet like usual, and I am calling the carpet company to re-tack to for $75 like usual. Even if the desk doesn't extend to the ceiling with crown, I don't want the desk to have a soggy feeling when you lean on it.

On this particular desk there are three lower units each 14" wide. They each only hit one stud in the wall. Screws or bolts into the wall wouldn't make it really tight especially since the walls of the house are nowhere near level. So I actually used construction adhesive to secure the base units to the concrete and screw it to the wall.

From contributor J:
If you cut the carpet, only cut it back far enough to sit the toe kick on the floor, just enough to where the carpet goes under it. Then sit the toe kick on the proper size blocking so it sits level. Shoot a row of nails into the floor just behind where the toe kick will sit, through the carpet to hold it from moving before you cut the carpet.

From contributor T:
Go over the carpet. The trick is to use those levelers that mount in the bottom on four corners of base cabinet. The feet are small enough to compress the carpet and concentrate the weight on the corners. Access is through the base cabinet floor.

It makes leveling a snap, and if it does give a little later, a screw driver will fix it quickly. If the holes are in a drawer stack, leave them as they are, otherwise use the plastic hole plugs that come with the unit for a more finished appearance.

From contributor B:
Since you built high-end cabinets, I would suggest cutting the carpet in the dimensions of the cabinet depth, then screw to the floorboards. The majority here seem to suggest keeping the carpet intact and make believe that it doesn't exist. I would agree to that, but in professional instance, I would cut the carpet with a sharp blade. It's not a big deal and a big job to just cut twenty inches of carpet to fit the cabinets. Let the cabinet have that footprint. It will not hurt the rest of the carpet in the room. As a skilled carpenter, I would cut the carpt. It only takes a 15-20 minutes to cut it, even though if its 10-20 feet in length.

From contributor R:
I have a thought about the type of carpet. Standard residential carpet is stretched out over padding, and commercial and some residential carpets are rubber backed and glued down, and are almost hard to compress. So whichever school of thought you attend, consider exactly what youre going up against (or down upon).

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor S:
Just imagine what happens when the Lord of the Manor or the CEO decides to replace that carpet, and gets to hear the carpetlayer's version of what you did, and how a real pro would have done it. That might be the impression that stays with your customer forever. He will not call you to see if you concur, because everything he will be told will seem reasonable. What happens then when he sits around the country club with the other local highrollers, and your workmanship comes up? You saved $75, right? Was it worth it? Explain up front to your customer what the options are. If you explain the extra $75 that your competitor omits in his sales pitch, you now sound like the guy who really knows his trade.

Comment from contributor A:
As a flooring contractor of 20+ years, I come across many cabinetmakers and remodellers as well as homeowners who ask me this question and I always offer the same advice.

A) Basic explanation: Cabinet height is best established from the subfloor up as the subfloor is a constant and flooring height is a variable.

B) Practical explanation: Flooring gets a lot more abuse than cabinetry. It is also subject to water damage to a greater extent, should there be a leak (gravity). so, the likelihood of the need to change floors is far greater than any vertical surface, hence it should not be 'trapped' by any cabinetry. Removing trapped flooring can also damage the cabinetry, creating unneccesary repair/unhappy clients.

In any case, always remember that our trade is called 'finish flooring' so that all other trades can work freely and not have to mask/cover/protect our work, which many don't, anyway.