Checking for Face Twist when Installing Cabinets

Advice for installers on how to make sure the face of a built-in cabinet isn't being pushed out of flatness by irregular, out-of-plumb house walls. November 5, 2013

I need to install a built-in cabinet, about 60"w x 42" tall x 12" deep into a drywall niche. The cabinet has a flanged face frame. I'm afraid that if I simply install the cabinet with the flange snug against the drywall all around, the studs may be racked, which would then rack the cabinet.

There will be columns installed to both sides and crown molding, so the cabinet does not need to be flush against the wall all around.

My question is, what's the best method to check that the cabinet face is not racking during installation? I want to get it as true as possible, because doors may be added later, but the doors are not there now.

Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor D:
Measure the diagonals. If they are equal it is square.

From the original questioner:
Maybe racking isn't the right term - maybe I should have said twisted. I'm concerned that even if the cabinet face is square by measuring diagonally, one corner would be out of plane with the front. I think it would still measure square, but the doors wouldn't close properly.

From contributor P:

If the columns are going to conceal the joint between the face frame and the wall anyway, why not just install the cabinet plumb? I would have the doors installed, as this is also a good way to check for twist.

From contributor F:
I have on rare occasions seen guys use string lines strung from corner to corner on the diagonals. If they don't just touch, then it's twisted. But seems to me that if both sides are installed plumb, then it can't be twisted. So don't use strings, just make sure each side of the cabinet is plumb with a nice accurate spirit level.

From contributor J:
It's just installation.

1. Once in place, check the bottom for level front to back, and side to side. It's easiest with a laser if you have one. Pull the case out and super glue shims to the base if the rear corners are low. Check again, and slip front shims under as needed. You need to be perfectly level.

2. Use a good level to assure all sides are plumb, both ways. Adjust as needed.

3. Final check the diagonals.

Doing these will guarantee no racking. If the flanges do not fit tight to the wall face, they will need something behind them at the voids. Rip shims and slip in with glue, or caulk if that works.

From contributor B:
If the cabinet has doors on it, go ahead and hang them before locking in the cabinet with the final screws. If the cabinet is racked or warped against the wall, the doors will not hang correct. It will be a quick indicator of what's up.

From contributor G:
I check for level as stated above, but then use Veritas bar gauge heads from Lee Valley to final check for square door openings.

From contributor M:
Easy way (no levels or string needed):

Install the cabinet. Stand back and eyeball it from the side. If the two end stiles don't sight in alignment, loosen the installation screw of the low corner, pull out the cabinet there, install a shim under the face frame lip there, and tighten the screw.

From contributor W:
Just as contributor M said. The same as the eye picking up on the doors being twisted, you should be able to eye the f/f flat. Out of level or not, you should only worry about a flat f/f and the cab fitting nice to the wall without having caulking.

From contributor F:
These are all good methods for checking, twisting, etc., but in this situation I would hang the doors before permanently attaching anything. I have had to have drywall floated out more than once to accommodate crooked walls.

From contributor W:
But he said there are no doors as of yet!

From contributor B:
Take 2 pieces of string and attach them from corner to corner with tape and create an x and note if the x touches in the center. If it doesn't touch, move the strings in and out to see which corner is out. Also check for plumb, level and square.

From contributor L:

From contributor V:
Level the floor of the niche, or put some sleepers in and level them. Then gently push said box in until it contacts the wall. Check plumb.

From contributor L:
Get yourself a good 32" level, so you can check the door opening plumb. Check both corners on each end - really eyeball the bubble (is it really in the middle). Both corners being plumb are a sure bet that you won't have any rack. If I didn't have doors, I would make some out of MDF, especially because it seems you will not be able to adjust the cab later.

From contributor Y:
All you need is a good 4' level. If both faces are plumb, there is no twist. Since you said there are going to be columns attached to either side so the edges of the face frame won't be exposed, this is irrelevant anyway. All you need to do is install the cabinet plumb and square. Shim where needed and do the same with the columns. Just leave yourself some scribe where they meet the walls.