Build a Corner Desk With IKEA ALEX Drawers in 8 Steps for 35% More Workspace

Why the corner triangle is worth reclaiming

A straight desk pushed against one wall leaves the adjacent wall doing nothing. Run a 120 cm worktop along wall A and a 120 cm return along wall B, joined across the corner, and the combined surface jumps from roughly 0.6 m2 to about 0.95 m2 once you account for the shared corner zone. That is the 35% figure in plain arithmetic, and it holds whenever both legs are at least 100 cm long.

The IKEA ALEX drawer unit measures 36 cm wide, 48 cm deep, and 70 cm tall. Two of them sit comfortably under a corner worktop as load-bearing legs, which removes the need for a separate frame on the drawer side. You still need support at the far ends and across the corner span, but the drawers carry the weight where they sit. The 70 cm height also lands close to the 72 to 74 cm most ergonomic guidance lists for a seated desk, so a worktop of 2 to 4 cm sets you in range without a riser.

Step 1 and 2: measure the real corner, then size the worktop

Interior corners are rarely 90 degrees. Hold a builder’s square against the join and check both walls with a spirit level before you cut anything. A 2 to 3 mm gap at the back is normal in older buildings; a 10 mm gap means you scribe the worktop to the wall or accept a visible triangle that you fill later.

Decide your two leg lengths next. A common pairing is 140 cm along the longer wall and 110 cm on the return, which gives a generous primary surface and a side run for a monitor arm or a second screen. IKEA sells the KARLBY and EKBACKEN worktops in lengths up to 246 cm, so a single board often yields both legs with one diagonal cut at the corner. Cut the corner join at 45 degrees on each piece so they meet in a clean mitre, or square-cut one piece and butt the second against it if you would rather avoid the mitre. The butt joint is faster and hides under a monitor most of the time.

Mark the cut on the underside, score the laminate or veneer with a knife along the line to stop chipping, and use a fine-tooth blade. For solid oak or oak-veneer KARLBY, a 48-tooth blade leaves an edge that needs only light sanding.

Step 3: seal the cut edges before assembly

Raw chipboard core under a laminate worktop swells the first time a glass sweats on it. Run a worktop sealer or even ordinary PVA wood glue along every cut edge and let it cure. On oak-veneer surfaces, the cut exposes end grain that drinks finish unevenly, so a thin coat of the same oil you plan to use later evens it out.

Step 4: finishing an oak worktop with hardwax oil

If you chose the KARLBY oak worktop, the factory finish is light and wears through at the front edge within a year of forearm contact. A hardwax oil such as Osmo Polyx 3032 or Rubio Monocoat builds a surface that resists coffee rings and reseals with a wipe instead of a full strip-and-sand. This is the same chemistry used on engineered oak flooring, where it survives foot traffic, so a desk that takes elbows and a mouse is well within its range.

Sand the worktop to 150 grit, then 180, vacuuming between passes. Wipe with a barely damp cloth to raise and knock back the grain. Apply the oil thin with a lint-free pad, working along the grain, and remove all surplus within ten minutes. A puddle left to sit stays tacky for days. Osmo lists eight to ten hours between coats and full cure at around two to three weeks, so plan the build around that wait or fit a temporary protective sheet while it hardens. Two thin coats outperform one thick coat every time, and the second coat needs roughly half the oil of the first.

The matt sheen reads warmer than the factory lacquer and shows fewer fingerprints. On the cut mitre, oil both faces before you join them so the join line does not stay pale.

Step 5: position and level the ALEX units

Stand both ALEX units in their corner positions, drawers facing out where you want them. Run the spirit level across both tops. Floors slope; a 4 mm difference over a 140 cm span tilts a pencil off the edge. ALEX has no adjustable feet, so shim the low unit with hardwood packers or self-adhesive felt pads stacked to the gap. Tape the level reading to the wall so you can re-check after you load the drawers, since a fully loaded unit settles a fraction.

Leave a 5 mm expansion gap between the back of each unit and the wall. The drawers run smoother when the carcass is dead plumb, and a unit jammed hard against an out-of-square wall racks the drawer slides over months of use.

Step 6: support the corner and the far ends

The two ALEX units carry the load directly above them. The unsupported spans are the corner zone and the far ends of each leg. For the far ends, an L-bracket into a wall stud holds well; find the stud with a detector and drive into timber, not into plasterboard alone, where a loaded bracket pulls out within weeks.

The corner is the weak point. A 45 by 45 mm timber batten fixed to both walls under the worktop, mitred at the corner, gives continuous support and doubles as the back rail. Alternatively a single steel corner gusset plate spans the diagonal. If you cannot fix into studs at the corner, a third short leg, even an upturned spare drawer carcass or a simple 70 cm post, removes the sag.

For anyone renting who cannot drill, the load path changes entirely. Damage-free wall hanging strips will not hold a worktop edge; they are rated for picture frames, not for a span you lean on. The honest answer for a no-drill build is to add a fourth support leg at each far end and treat the walls as decoration only.

Step 7: fix the worktop to the drawers

Drive short screws up through the top panel of each ALEX unit into the underside of the worktop. The ALEX top is chipboard, so use 16 to 20 mm screws and pilot-drill to avoid splitting. Four screws per unit lock the worktop without it shifting when you open a drawer. On the corner batten, drive screws down through the worktop into the timber, countersunk and filled if the top surface matters to you, or up from below if you want a clean top face.

Keep screw length under the worktop thickness. A 28 mm laminate top takes a 20 mm screw with margin; a screw tip breaking through the finished surface ruins the work from Step 4.

Step 8: the back gap, paint, and the wall behind

With the worktop fixed, the gap between its back edge and an out-of-square wall is now fixed too. Fill anything under 5 mm with a flexible decorator’s caulk in a tone near the worktop. Anything larger gets a scribe strip, a thin length of matching timber cut to follow the wall line and pinned to the worktop edge.

The wall behind a corner desk reads in every video call, so it earns a coat of paint chosen for low glare. A Farrow and Ball estate emulsion in a mid-depth shade like Pigeon or De Nimes sits flat under a ring light and hides scuffs better than a brilliant white, which bounces screen glare straight back into the lens. Two coats over a primed plaster wall is standard. Cut in around any bracket you fitted in Step 6 before the worktop went on, since a brush cannot reach behind a fixed top afterward.

Load the drawers low and heavy. The bottom ALEX drawer takes books and hardware; the top shallow drawers suit cables and pens. A fully loaded unit weighs enough to anchor the whole assembly, which is why the level check from Step 5 matters more after the build than during it.

What this build does not solve

The corner desk reclaims surface, but it fixes your monitor distance to whichever leg you sit centred on. Whether the return leg becomes genuine working space or just a shelf for things you never file is the question the worktop area alone cannot answer.