Build a Banquette Bench With IKEA SEKTION Cabinets in 9 Steps
A 20 cm SEKTION base cabinet box, laid on its back, becomes a bench seat with internal storage for the cost of a single cabinet plus a plinth kit. The build uses no custom joinery, holds the weight of two adults across a 90 cm span, and leaves the toe-kick recess for foot clearance. Here is the sequence, the fasteners, and where the math gets tight.
SEKTION base cabinets ship in three depths (37, 60, and a frame depth of 73 cm) and several widths. For a banquette, the 60 cm depth cabinet turned on its back gives a seat 60 cm deep, which is roughly 20 cm too deep for comfortable sitting. The fix is the 37 cm depth box, which produces a seat depth of 37 cm once the doors face up and become the lid. That dimension sits at the lower end of the 40 to 48 cm range most dining benches use, so a 6 cm seat cushion brings the usable depth back into a comfortable zone.
The load case matters before anything else. A SEKTION box is 18 mm particleboard with a melamine face, rated by IKEA for shelf loads, not for two people sitting on the long edge. Laid on its back the box transfers weight straight down through the side panels into the floor, which is the strong orientation. The weak point is the back panel, a 5 mm hardboard sheet that carries no structural load. That detail drives several decisions below.
Pick the box and check the corner geometry first
Start with a 37 x 76 cm SEKTION base cabinet for a single seat, or two 37 x 60 cm boxes butted end to end for a 120 cm run. Lay the assembled box on its back so the open face points up. The interior becomes a storage well; the toe-kick cut on the original bottom panel now faces forward and gives 8 to 10 cm of foot recess at floor level, which is why the bench does not force you to tuck your feet under.
Measure the corner where the banquette meets the wall before buying. An L-shaped banquette needs the two runs to meet at a true 90 degrees, and most domestic walls are out by 3 to 8 mm over a metre. A framing square laid into the corner shows the gap. If the corner is open more than 5 mm, plan a scribe strip: a 20 mm wide poplar batten you plane down to follow the wall line, fixed to the back of the cabinet run with the wall-side cabinet sitting tight. Skipping this leaves a wedge-shaped gap that no cushion hides.
Level the boxes on the SEKTION legs, then lock them
SEKTION uses adjustable plastic legs (the IKEA part is the Capita-style integrated foot on newer boxes, or the separate leg kit) with about 25 mm of vertical travel. Clip four legs per box and set the nominal seat height. Finished seat height for a dining banquette runs 43 to 48 cm including the cushion; working back from a 6 cm cushion that compresses to roughly 4 cm under load, set the hard box top to around 40 cm.
Put a 60 cm spirit level across the top in both directions. Adjust the legs until the bubble centres, then check that adjacent boxes read level to each other and not just individually, because a 2 mm step between two boxes telegraphs through the seat lid. Once level, connect adjacent cabinets through the side panels with the IKEA connecting screws, two per joint, drilled through pre-marked points. This stops the run from racking when someone slides along the seat.
Anchor the back to the wall so the bench cannot tip
The back hardboard panel will not hold a fastener, so the anchor has to pass through the top rail or a back-mounted cleat into the structure behind. Run a 45 x 45 mm timber cleat horizontally across the back of the cabinets at the height of the top rail. Fix the cabinets to the cleat with 4 x 40 mm screws into the side panels, then fix the cleat to the wall.
The wall material decides the fixing. Into a masonry wall, mark and drill 8 mm holes for nylon wall plugs and 5 x 60 mm screws, one plug every 400 mm. Into plasterboard with no stud behind, the load is pull-out resistant at the cleat but tip resistant only with proper hollow-wall anchors. Spring toggle bolts, the same M5 toggle bolt pattern used for hanging a heavy mirror, hold 20 to 30 kg each in 12.5 mm plasterboard, so four toggles across a 76 cm cleat give a wide margin against a person leaning back. Where a stud is available, a 5 x 70 mm screw straight into the timber beats any cavity fixing.
Build the seat lid as a hinged top
The lid is the part that takes daily abuse. Cut 18 mm birch plywood to the box footprint plus a 15 mm overhang on the front and exposed sides; the overhang keeps knuckles off the cabinet edge when lifting. Round the front edge with a 6 mm roundover bit or sand it to a soft radius, because a square plywood edge under a cushion wears through fabric in months.
Hinge the lid at the back to the timber cleat using two 75 mm butt hinges or a continuous piano hinge for a 120 cm run. A piano hinge spreads the load and stops the lid sagging at the unhinged corner over time. Add two soft-close lid stays rated for the lid weight so the top does not slam on fingers reaching into the storage well. Test the swing before fixing cushions: the lid must clear any wall trim or window sill behind it through the full arc.
For the storage well itself, leave the SEKTION interior as melamine or line the base with a 4 mm felt mat to stop stored items sliding and scuffing. The well depth on a 37 cm box laid down is about 33 cm usable, deep enough for board games, table linen, or seasonal items, shallow enough that nothing disappears to the bottom unreached.
A note on cushion depth
A 6 cm high-resilience foam cushion at 35 kg/m3 density holds its shape across years of daily use; a 4 cm cushion bottoms out and the plywood edge makes itself felt within weeks. Order the foam 1 cm larger than the lid on each side so the cover stretches taut.
Finish the visible faces to match the room
SEKTION doors and cover panels come in finishes that rarely match an existing dining wall, so painting the exposed cabinet sides and any cover panel pulls the bench into the room. Melamine needs a bonding primer first; a standard wall emulsion peels off the slick face within a season. After priming, two coats of eggshell in a colour like Farrow and Ball Hague Blue or Railings give a hard-wearing low-sheen surface that takes wiping. Eggshell resists the scuffing a matt finish cannot survive at shin height.
If the banquette sits against a wall you are also tiling, the order of work matters. A zellige tile backsplash above the bench, set with the cabinet run already in place, lets you scribe the bottom tile course to the cleat line and avoid a cut sliver at the join. Zellige is hand-made and varies 1 to 3 mm per tile, so the bottom course against a level bench top reads better than against an uneven skirting. Tile after the cabinets are anchored and before the cushions go in, so grout splashes land on bare plywood and wipe clean.
Where the build gets tight
The single hardest measurement is the relationship between finished seat height and the table apron. A standard dining table sits with its top at 74 to 76 cm and an apron that drops 5 to 8 cm below that. With a 44 cm seat, the gap from cushion to underside of apron is around 24 cm, which is comfortable thigh clearance. Push the seat to 48 cm to clear a deep storage well and that clearance shrinks to 20 cm, at which point taller sitters knock knees on the apron. The storage depth and the seat comfort pull against each other, and the box depth you chose at the start sets the limit on how far you can move either.
Does the 37 cm box truly need a 6 cm cushion to read as a finished bench, or would a thinner seat work over a softer foam grade you have not specified yet? That trade between foam thickness and foam density is the one variable this sequence leaves open.
