Avoiding Twist when Installing Cabinets

Installers share their messages for getting cabinets plumb, square, and level during the installation process. March 22, 2013

Question
I've had issues at times with uppers twisting as they are screwed to the wall. I have used the ledger undernailer method lately (1/2" nailer on cab and 1/2" ledger on wall shimmed straight) and it works well, but is time consuming due to the double work of installing a ledger and shimming straight. It occurred to me to hang the cabs like a pre-hung door, with the door in its frame. Does anyone have any thoughts regarding this?

Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor J:
Hanging the cabinets with the doors on is a bad idea. All they will do is get in the way and possible get damaged. They will not in any way help keep the cabinet square while hanging. Use shims to stop the cabinet from being twisted out of shape. Start in a corner or at the end of a run and get that first cabinet plumb and level. Then screw the next cabinet to the first cabinet, shim as required, and then screw to the wall. Use the Camar hanging rails. You screw a steel rail to the wall level where the cabinets need to go, and then you simply hang the uppers off this rail. The Camar system has adjustments to level the cabinets.



From the original questioner:
I'll check out the Camar rail. I didn't mean hanging the cabinet with doors on to keep the cab square, but rather to use the doors as a reference to see if the cab is kept square and twist free.


From contributor J:
You shouldn't need the doors on to see if the cabinet is being pulled out of square. When driving the screws in to the wall, and once they seat, if the cabinet moves as you are tightening the screw it is being pulled out of square. At this point you need to add some shims.


From contributor C:
The hinge hardware on your boxes should have enough adjustment in them to account for slight variances in your boxes being out of square. Keep in mind I said slight! I agree that hanging the boxes with the doors on is a bad idea since they are always flopping around and just add extra weight. Just to restate the obvious and standard install procedure, when you install your first cabinet make sure it’s as square and level as possible. Then use that as a reference point for your other boxes. You can tell when a box is being pulled out of square, and you should always be checking for level and plumb as you work your way down the wall. I know this isn't much help, but this is the way I have always done it and have always been successful.


From contributor W:
I would still shim the hanging rail between the high point of the wall and any low points so that the rail is not bowed, thus keeping the front and back edges of the cabinet in straight line.


From contributor O:
If you can get away with the extra depth hanging off a cleat is a definite win/win situation. It helps to hang the cab and helps so you don’t have to screw your cab tighter and tighter to the wall (thus pulling it out of square). It could be that the walls are bowed or cupped or not plumb thus adding new and interesting dimensions to your work! Don’t let the walls dictate the squareness of your cabs, use shims or a cleat system.


From contributor M:
I fab and install for a lot of old houses and I always use the doors as reference. I install level, clip on the doors, and then plumb/rack with shims. It works great. A long upper can have twist that is a lot harder to detect with a level on the face than it is with pre-hung doors.


From contributor B:
Just a quick word of warning about a situation I ran into. I would quite often, as Contributor M suggested, get my first cabinet hung level and plumb and then clip on a door to confirm that everything was good to go. I did one install where nothing that I tried seemed to be working. The door itself was 1/4" out of square, so be careful.


From the original questioner:
A 1/4" out of square? Wow! How did the job look after you finished?


From contributor B:
Great! After I had the supplier remake all the defective doors.


From contributor R:
The trick to hanging cabinets is to know what’s coming before you get there. The first thing I do is find the high and low spots on the floor. The second thing is to throw a straight edge on the wall to look for bulges. I usually will float my installs till they’re all in. I mark out the wall for studs, pilot drill 3/16 for screws on the backs of the cabinets, screw all the lowers together and place (a few screws not torqued in), and then I’ll use supports to suspend the uppers on the wall at the right height, screwing them together as I go. I put a few screws through the pilot holes to keep them from falling, but I don’t over tighten.

What I have done is lay a six foot level on the wall and lay a framing square against that and the cabinet side - this will tell you if the walls are bulging out or falling away. I’ll even screw all three cabinets together for a corner before lifting into place. There’s not enough room here to write it all but the trick is to keep a lookout for what’s coming. Float it on the wall if the walls are bad as the cabinets will naturally stay straight and square this way. Use a few shims as you go to keep them plumb but don’t screw off until satisfied. When you screw the cabinets in pop the shims in slightly more than they need so when you tighten the screws they won’t distort.



From contributor A:
Contributor O, Contributor M, and Contributor R have it on the money. French cleats or hanging rails can save the day i you can get away with them, or design them in when you build. I always find it helpful to fasten as much together (level) before doing the plumb and square tweaks. It’s much easier when boxes are hanging on the wall on your freshly-mounted, level hanging rail! I'll even shim the cleat/rail off the wall as necessary if I have to. Then using the doors as a final reality check is the proof (assuming you have square doors).