Built-In Bookcases for a Sloping Floor

Woodworkers discuss ways to adapt a built-in bookcase to a severely sloped floor. September 5, 2006

I'm building a set of built-in bookcases for a client in a room that was converted from a screened in porch. The floor was framed on an old flat roof and as a result is sloped about 1 1/2" over just a 7 1/2' run. My question revolves around how to handle such a slope. The bookcases consist of a lower and upper unit and will run the entire length of the 7 1/2' space. If I use a simple base molding for the bottom unit, it is going to be 4" tall at the upper end and 5 1/2" at the lower (the client doesn't want a toe-kick). I'm afraid that this is going to be very noticeable but I'm not sure of any other way to handle it if I want everything else to be level. Any other ideas?

Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor M:
Is the client aware of the issue? If not, I would bring it to their attention. You are right, that much of a slope will be quite noticeable, with or without a toekick. It will not be easy to hide such a thing, and if I were given the opportunity, I would probably suggest leveling the floor in some manner so as to avoid having to hack up your cabinets. Simplest solution would be to remove the existing flooring and add some 2x onto the joists tapered from nothing to 1 1/2". May seem like a lot of work, but it will really make a difference in the end.

From contributor D:
Your job is building and installing cabinets. Inform the client of the situation and they can decide to fix the floor or not. If you want to do it they can hire you, or someone else. Custom cabinets, in my opinion, doesn't mean tapered cabinets. No floor or wall is ever perfect and it's not hard to make most work, but extreme situations are a different story.

From contributor L:
I deal with this all the time. I call it Old House Syndrome. Most of my clients live in 18th century homes and are very aware of the way the floors, walls and ceilings slope. Nothing is square, flat, straight or true. Tell your client of the situation, though they are probably aware of it. Just make the toe kick area big enough to scribe the 1 1/2". If everything is in line, then it should look pretty good. If this is not acceptable to them, they will need to level the floor and this shouldn't be your responsibility unless you want to undertake the project.

From contributor I:
I think in this situation I would suggest a sort of platform that would go under the bookcase. Start about 4" at the high end and make this level so as to be 5 1/2" at the other. Make this wide enough to act as a step to the higher shelves, maybe 6" to 8 ". I believe this will solve the view of the slope. And your cabinet will be made square unless the ceiling follows the floor. You could just make the step wide enough to sit on to read.

From the original questioner:
Thanks for your input. I told (and showed) the client that the floor is severely sloped. In fact, just by standing in the space, you can tell it is sloped. They are aware that the base molding may have to be tapered and, although they would prefer it not to be, understand that it is because of the floor and not the cabinets.

Unfortunately, the space was recently renovated and the floors are new, so I'm sure they will not want to consider redoing them. I agree the ideal solution would have been to fix the floors correctly in the first place, but I was called in after that work had already been done.

The platform idea sounds like something I considered, but I had not considered extending it forward as a step. That would definitely make the taper appear to be less severe, and I think would add some interesting detail. Thanks, everyone, for your help.

From contributor C:
The platform material should match the floor, with the contrasting cabinetry sitting on it. This should make the sloping platform hardly noticeable. Don't forget to charge for building the platform - it really isn't part of the cabinet as much as a correction of a faulty site condition.

From contributor L:
I'm assuming you are building a face frame cabinet, but this method works for frameless as well. Rout a scribe rabbet across the face of the bottom rail/stiles to whatever depth you like... say 3/8"d by 1"w, then inlay a piece that has been scribed to the sloping floor. If you make the scribe piece the same depth as the scribe rabbet (3/8"), you can sand it flush. You can also make the fitted scribe piece thicker so it looks like a step or base moulding. It's just like scribing a cabinet end to a wall.

From contributor J:
I like the platform idea. Remember, a normal step height runs from 7 1/4 to about 8 1/4, in this case close enough. I, if possible, would make it deep enough so you could walk in front of the cabinets, and start the height about that 7ish point. This way, it looks like it really does belong.