Alcoves either side of a chimney breast are the classic spot for fitted cupboards and shelving, and almost none of them are square. Walls lean, chimney breasts taper, floors slope and ceilings dip. A good survey finds all of that before you cut anything, so the units fit first time and the scribing is a tidy finishing job rather than a rescue.
This is the method we'd use: what to measure, in what order, and what to write down.
What to take
- A good tape (5 m or 8 m) and a laser measure for heights and long runs
- A long spirit level (1.2 m or more) and a short one
- A straight edge, to find bows and humps in the walls
- A square, a pencil and something to sketch on (paper, a tablet, or straight into JoinerKit)
- Your phone, for photos with the tape in shot
Measure the width at three heights
Measure the alcove's width just above the skirting, at about the middle, and just under the ceiling or coving. Write all three down. It's normal for them to differ by 10 mm or more, because the side walls are rarely parallel.
Build to the narrowest width, less a small fitting allowance, and close the gaps with a scribe. Many joiners leave around 5 to 10 mm each side and scribe a face frame, a scribe strip or a filler to the wall; the right amount depends on how far out the walls are and how you like to finish.
Measure at the front edge of the chimney breast as well as at the back wall. On older houses the alcove is often wider at the back than at the front, or the other way round.
Check the walls for plumb and flat
Hold the level against each side wall and the back wall. Note which way each one leans and roughly how much over its height (for example "left wall leans out 8 mm at the top"). Then run the straight edge across each wall to find bows or humps, which matter where a unit's side or back will sit against it.
Chimney breasts are often out in both directions. If a unit's side sits against the breast, its scribe has to follow the breast, not the other wall.
Depth, height and the floor
Measure the depth from the back wall to the face of the chimney breast at the top and at the bottom. Then decide how deep the units should be: whether they stand flush with the breast, sit back from it, or stand proud of it, and whether doors need to open past it without catching.
Measure floor to ceiling at the front and back of each corner. Floors and ceilings are rarely level, so put a level on the floor across the alcove too, and note the high and low points. The plinth or the base has to take up the difference, and units that go up to the ceiling need a scribe or a cornice at the top.
Note everything in the way
Measure the position of everything that affects the units from one fixed corner, and write it on your sketch:
- Skirting: its height and thickness, and whether it stays (scribe round it) or comes off
- Sockets, switches, aerial and data points, and whether they need moving or cutting round
- Radiators and pipes, gas meters and anything boxed in
- Picture rails, dado rails, coving and window reveals
- Where the floor and ceiling joists run, if anything needs fixing to them
Write it down so you can build from it
Draw a quick front view of each alcove with every measurement on it, plus a plan view showing the depth. Take photos of each wall with the tape in shot, and of anything awkward. Two weeks later in the workshop, those photos answer questions you didn't think to ask on the day.
Mistakes that catch people out: measuring the width at one height only, forgetting the skirting, not checking whether doors clear the chimney breast, and assuming the ceiling is level.
From measurements to a design
In JoinerKit you put in the wall's width, height and depth, the chimney breast and any scribe allowance at the sides and top. The units are then drawn to that real space, and you'll get a warning if one strays into the scribe zone. The cutting list, sheet layouts and a price come from the same drawing.
Questions
How much gap should I leave when fitting alcove units?
Build to the narrowest width of the alcove and leave a small allowance each side, commonly around 5 to 10 mm, then scribe a face frame, scribe strip or filler to the wall. The more the walls are out, the more you'll want to allow.
What depth should alcove cupboards be?
It depends on the alcove and what's going in. Shelving above is often 250 to 350 mm deep and base cupboards deeper, often up to the face of the chimney breast. Check the doors can open without catching the breast.
Should fitted alcove units go up to the ceiling?
They can, and it looks built-in, but the ceiling is rarely level. Allow for a scribe or a cornice at the top so the unit can be fitted to the ceiling's line.