How to Scribe Kitchen Cabinets to a Wall That Isn't Straight

Every fitter learns this the hard way at least once. You build a run of cabinets dead square, carry it in, push it against the wall, and there's a gap at the top you could post a letter through.

That's not bad cabinetmaking. That's just what walls are like. Drywall sags, plaster bulges, old plastered walls can be out by half an inch over a run or more. Scribing is how you make a square cabinet fit a wall that isn't.

1Check the wall before you touch a cabinet

Don't skip this bit. Run a straightedge or a level up the wall where the end panel or filler will land, top to bottom.

Look for the worst spot. Usually it's a lump of old plaster, a stud that's bowed, or a corner that's never been square since the house was built. Note where the gap is biggest, because that's the number you'll work from later.

2Leave extra material when you cut the end panel

This is the step people forget, and it's the one that saves the job. If you cut your end panel or filler to the exact finished width, you've got nothing to scribe off.

A good rule is to add at least a quarter inch over what you measured if the wall looks fairly straight, and up to half an inch if it's visibly out. When you're building your cutting list, build that allowance in from the start rather than trying to add it on site with a plane and a prayer.

3Set the cabinet and scribe the line

Get the cabinet or the run level and plumb first, using shims under the base if you need to. Don't skip leveling just because you're planning to scribe. Scribing fixes the wall contact line, not the whole cabinet's position.

Once it's sitting where it needs to be, run a compass along the wall with the point riding the wall and the pencil marking the panel. Keep the compass gap steady the whole way. That line is now the exact shape of your wall, transferred onto wood.

4Rough it out, then sneak up on the line

Don't try to hit that pencil line in one pass. Rough the waste off first with a jigsaw, staying a hair outside the line, then work in with a block plane or a power plane.

Go slow for the last few passes. It's much easier to take off one more sliver than to put wood back on. If it's a painted or laminated panel, a sharp block plane set fine will leave a cleaner edge than sanding.

5Back-bevel the edge so only the front touches

Here's a trick that makes scribing forgiving instead of fiddly. Cut your scribe edge with a slight back angle, maybe five to ten degrees, so the very front edge of the panel is what actually touches the wall.

That way, if the wall's contour is slightly different a few millimetres back from the face, you won't see it. Only that thin front line has to be perfect, not the whole depth of the cut.

6Watch out for corners, two walls at once

A single scribe against one wall is straightforward. An end panel that has to sit into an inside corner, touching two walls at once, is where things go wrong fast.

Scribing one face can throw off the fit on the other. The fix is to make a quick template out of scrap ply or hardboard first. Scribe the template to both walls separately, check it sits tight in the corner, then trace it onto your actual panel. It takes ten extra minutes and saves you from ruining a finished end panel.

7Fit it, fasten it, then deal with what's left

Slide the scribed panel back in and check it along the full length before you reach for a screw. A small, even gap you can fill with caulk is fine. A gap that gets wider in one spot means you missed the line somewhere back in step four.

Fasten the cabinet through the back or sides as you normally would, keeping it level and plumb, not just tight to the wall. A perfectly scribed panel against a cabinet that's racked out of square will still give you doors that won't close right.

• Check the wall with a straightedge before you cut anything
• Build scribe allowance into the cutting list, not as an afterthought on site
• Level and plumb the cabinet first, scribe second
• Rough cut outside the line, then plane down to it in small passes
• Back-bevel the edge so only the front line has to be exact
• Template inside corners before you touch the real panel
• Check the full length of the gap before you fasten anything down