Two Lagkapten Tops Joined over Alex Drawers for a 3-Metre Home Office Desk

The 280 cm run people call 3 m

A Lagkapten top is 140 cm long and 60 cm deep, so a pair placed end to end gives 280 cm of actual desktop. Reaching a full 3 metres means one of two arrangements: the join overlaps a central Alex unit, or the builder accepts the 280 cm surface and counts the wider footprint created by the drawer units. Many desks described as 3 metres use a small gap bridged by the cabinet carcass below, which can push the effective footprint past 290 cm once the central drawer stack sits proud.

Put the seam where the cabinet can carry it

The Alex drawer unit is 36 cm wide and 70 cm tall in the standard nine-drawer version. The six-drawer version measures 36 x 48 cm. With one Alex at each end and a third under the join, the two Lagkapten tops have three support points across the run instead of a long unsupported middle.

That spacing does more work than the thickness of the desktop. Lagkapten uses a hollow particleboard core faced with melamine, so it behaves differently from a slab of solid wood. Once the unsupported span moves past 90 cm, a 4 kg monitor arm clamped near the middle is enough to make the surface deflect.

The two tops meet edge to edge, and the melamine faces do not bond to each other in any useful way. Glue on that surface has almost nothing to grip. A seam that stays flat needs a mechanical connection below the panels.

A common way to do it is an 18 mm plywood rail under the join, cut 200 mm wide and long enough to run 400 mm on each side of the seam. Screwed upward from below, that rail keeps the two tops in one plane. The limitation is inside the Lagkapten itself: screws hold only where the top has solid material.

The perimeter of a Lagkapten top has a solid rail roughly 30 to 40 mm deep. The centre is honeycomb board or void. A screw driven into that empty centre will spin and hold nothing, no matter how carefully the rail is cut.

That makes screw placement the real join detail. The plywood spline has to catch the solid perimeter of each top, or the fixing has to go down into the Alex carcass so the drawer unit provides the alignment. Placing the third Alex precisely under the seam solves both jobs at once.

The top of the Alex is 36 cm wide, enough to carry 18 cm of each Lagkapten top. With pilot holes drilled first, screws can pass through the Lagkapten and into the chipboard top panel of the drawer unit. The cabinet then becomes the seam support as well as the centre leg.

A monitor arm changes the load because it concentrates weight at a clamp instead of spreading it over feet. Near the middle of a hollow-core panel, that clamp is asking the weakest part of the top to resist a twisting load. Moving the seam over the Alex unit does not make the desktop solid, but it takes the most vulnerable joint out of free span.

Drawer runners under real loads

Alex drawers ship with basic epoxy-coated side runners meant for light stationery loads. Filled with lever-arch files and camera gear, the bottom drawers in a nine-drawer Alex can start to sag on those runners within weeks. The problem shows up first low in the stack because those drawers tend to carry the heaviest items and get pulled hard.

IKEA’s Sektion kitchen line uses full-extension undermount runners with soft-close. Several of the Maximera-style runners can be retrofitted into an Alex carcass if new mounting holes are drilled. The swap is possible, but the geometry does not map one to one from a kitchen cabinet to the narrower drawer unit.

Alex is 36 cm wide internally at a tighter tolerance than a Sektion base cabinet, and the Maximera runner expects a particular carcass depth. On the 58 cm deep Alex, the clean retrofit uses a 12 mm plywood spacer batten on each interior wall. Those battens bring the runner mounting faces to the offset the undermount hardware expects.

That change turns the drawer from a side-mount partial-extension box into something close to a full-extension soft-close drawer. Under a 15 kg load in the bottom drawer, the difference is visible: the drawer comes out far enough to show its full contents, while the stock runner stops at about two-thirds of the depth.

A pair of Maximera runners costs several times the implied per-drawer price of the stock Alex hardware. Replacing the hardware on all nine drawers of a tall Alex rarely earns back the cost. The practical version is to upgrade the two bottom drawers, since those are the ones carrying the weight and taking the hardest pull.

Drilling for the retrofit also changes the relationship between the drawer box and the front. A runner mounted a few millimetres out of line can make the drawer close softly while leaving the reveal uneven. The hardware upgrade should therefore be laid out with the fronts temporarily fitted, because the runner position and the visible face alignment are tied together.

Custom fronts and the Alex tolerance problem

Superfront makes replacement fronts, legs, and handles sized to fit Alex, Kallax, and Besta carcasses. On the desk build, the relevant part is the Alex drawer front. Swapping the flat white front for oak veneer or a painted linoleum surface changes the read of the desk from recognisably IKEA to more like fitted joinery, while the support structure underneath remains the same.

Alex has been revised across its production runs, and an older carcass can sit a millimetre or two away from the current specification. Superfront fronts are cut to IKEA carcass dimensions, so that small difference matters at the reveal. A front made for the current Alex will bolt straight onto the existing drawer-front fixing points when the carcass matches the present spec.

A front cut for a discontinued width can leave a reveal that is uneven from top to bottom. That is mostly a visual problem on a stock drawer, but it becomes harder to diagnose after a runner retrofit because the box position has also been altered. The drawer can slide properly and still look wrong from the chair side of the desk.

A front cut for a current carcass can still meet a drawer box whose runner holes have moved, leaving the reveal to answer a measurement the catalogue never gives.