Build a Floating Vanity With IKEA GODMORGON Units in 8 Steps for 30% More Storage

Why the wall takes the load before the cabinet does

The GODMORGON suspension system hangs from a single horizontal aluminium rail fixed to the wall. That rail is the piece between a loaded vanity and a cracked floor tile, so the cabinet rating tells only part of the story.

IKEA rates the standard 100 cm unit for a distributed load in the region of 25 kg per cabinet. The working limit, however, comes from the material behind the rail. In solid masonry with M8 frame fixings, the assembly will hold far more than the contents of two basins and a stack of towels. In 12.5 mm plasterboard with empty cavity behind it, the supplied anchors should not be treated as a structural answer.

A timber pattress is the honest repair for that wall. Cut a length of 18 mm WBP plywood, screw it through the plasterboard into at least two studs, then mount the IKEA rail to the plywood. The plywood spreads the moment arm across the wall instead of asking two cavity anchors to take the whole load. A full floating vanity combines downward load with outward rotation at the bottom edge, levering the top fixings away from the wall. Cheap anchors resist that failure mode badly.

Steps 1 to 3: rail height, services, and the rear panel cut

Mark the rail centreline at 85 to 90 cm above finished floor level when the target basin rim height is around the conventional 80 to 85 cm. The GODMORGON cabinet hangs below the rail, so the rail itself sits high.

A 3 cm error is enough to make the basin crowd a tall user or force a child to reach. Set the line with a laser level. A spirit level held on a 100 cm rail can hide a 1 mm bubble error, and that small error reads as a 4 mm drop across the run.

Locate the waste and supply before drilling. A floating unit hides the trap inside the carcass, which means the waste pipe enters through the back panel at a height chosen before the cabinet is hung.

The standard GODMORGON back panel has a knockout. If an existing 40 mm waste exits the wall at 55 cm and the cabinet back wants it at 50 cm, the mismatch has to be resolved in pipework or joinery. Pencil both pipes onto the wall first, then compare them with the actual cabinet back.

Cut the rear panel with a jigsaw and a fine downcut blade to keep the melamine from chipping. The cut is the one you cannot disguise once the pipe is in place.

Seal the exposed chipboard edge with clear silicone. Water that wicks into an unsealed cut edge swells the panel within two winters.

A short note on the worktop

A solid oak or walnut top over GODMORGON drawers wants a hardwax oil made for worktops. Film varnish chips at the splash zone, while Osmo TopOil and Rubio Monocoat penetrate the grain and can be re-coated without sanding back to bare wood.

Steps 4 to 6: hanging the carcass, fitting the trap, sealing the top

Lift the empty carcass onto the rail with two people, because a 100 cm GODMORGON cabinet is difficult to control alone. The back hook engages a continuous lip that disappears from view once the unit is against the wall.

Slide the cabinet left to the pencil mark. Drive the security screws IKEA supplies through the back rail into the pattress. Those screws do structural work: they stop the cabinet walking off the rail when a drawer is yanked open at full extension with 8 kg of toiletries riding in it.

A wall-hung vanity almost always needs a space-saving bottle trap or a shallow P-trap. The standard bottle trap eats the depth of the bottom drawer. McAlpine and Viega both make 40 mm low-profile traps that recover most of that drawer. Dry-fit the trap before cutting the drawer back, mark where the pipe intrudes, then notch the drawer base around it. A clean U-shaped notch is stronger than a torn rectangular hole that flexes every time the drawer is loaded.

The brackets holding the basin to the worktop, or the worktop to the carcass, are easy to ignore because they vanish after the install. GODMORGON ALDERN and similar tops sit on the cabinet top edge and need sanitary silicone along the rear wall join. Apply one continuous bead and tool it with a wet finger in a single pass. Stop-start beads trap water at every break.

Steps 7 to 8: levelling under load and the final silicone bead

Hang the doors and drawers empty, then check the gaps before loading the cabinet. The rail flexes microscopically once 20 kg goes inside, and a vanity levelled empty can drift out of true after towels, bottles, and basins are in place. GODMORGON drawer fronts adjust on a cam at the bracket; a quarter turn moves the front about 1 mm. Set the reveal between fronts to a consistent 3 mm gap by eye against a steel rule, working top to bottom so gravity can assist the alignment.

The final silicone bead seals the worktop to the wall and the basin to the worktop. Mask both sides with low-tack tape 2 mm off the joint, gun the bead, tool it once, then pull the tape immediately before the silicone skins. Tape pulled after skinning drags a ragged edge through the cured surface. A north facing bathroom with little direct light will show silicone discolouration over time, which is one reason to use a translucent neutral cure product instead of a bright white that yellows.

Where the 30% storage figure comes from

A freestanding 80 cm vanity loses roughly 10 cm of usable depth at the bottom to a recessed toe-kick and another slice to the plinth structure. It also interrupts the carcass with a fixed shelf above the door. The GODMORGON layout removes the doors and toe-kick from that equation and uses full-extension drawers that run the entire 47 cm depth, so the volume formerly stranded behind a hinged door becomes storage pulled fully into the room.

On a 100 cm unit, two drawers at 47 cm depth, 90 cm internal width, and an average 18 cm usable height give roughly 0.15 cubic metres of accessible volume. A comparable two-door freestanding unit with one internal shelf, the same footprint, and a 38 cm reachable depth after the toe-kick and rear dead zone lands nearer 0.11 cubic metres of volume that can be used without kneeling and groping. That difference is the 30%, with reachability doing most of the work; raw cubic capacity explains little.

Trap and waste positions reduce that clean figure. The trap and waste steal a corner of whichever drawer they pass through, and a basin with a deep ceramic bowl can intrude into the top drawer as well. The clean 30% assumes a shallow basin and a low-profile trap. Specify a deep undermount basin and a bog-standard bottle trap and the gain shrinks toward 18%, because the bottom drawer becomes a tray with a pipe through it.

Everything above assumes you have found studs or solid masonry. On a stud wall where the studs fall at the wrong centres for the rail, the pattress is required. An 18 mm plywood pattress adds 18 mm of standoff that pushes the whole vanity proud of the wall unless you recess it. Recessing a pattress into plasterboard means cutting the board back, packing the void, and re-skimming, which is a half-day job absent from the GODMORGON instruction sheet.

The drawer that reports the fixing

Full-extension runners carrying weight at 47 cm of reach develop a tell. If the bottom drawer starts dropping at the front when open, the carcass has racked slightly because the security screws went into plasterboard with no timber behind. The drawer is reporting on the fixing, and that is the part of this build you cannot inspect once the towels are folded and the cabinet looks finished.

The shallow basin that preserves drawer volume also sends splash toward the worktop join more readily. The visible installation can look finished while the unresolved part of the build remains inside the wall and along the sealed rear edge.