Flat pack kitchen units, what you actually get for the money

Summary: Flat pack kitchen units can be genuinely good value, but the box price hides worktops, fitting, filler strips, hardware quality, and the reality of walls that are not square. Compare panel thickness, backs, runners, standard widths, and installation effort before choosing the cheapest kitchen.

The first flat-pack kitchen I helped install was in a rental in Haarlem and it cost 1,180 euros for the boxes and another 240 for the worktop. I was 27. The wall was about 3.4 m long, give or take a centimetre, and the previous tenant had left a hole behind the cooker that you could put a fist through. The boxes were cheap. Making them look like a kitchen took the weekend.

What I learned that weekend, and a few kitchens later, is that "flat pack kitchen units" covers a much wider range of things than the phrase suggests. Some of it is genuinely good. Some of it is the cheapest furniture you can legally sell. The price tags don't always tell you which is which.

What's in the box, actually

A flat pack kitchen unit is, almost always, five or six panels and a hardware bag. The panels are the two sides, the bottom, the back, and a top rail or solid top depending on whether it's a wall cabinet or a base unit. The back panel is usually the giveaway. A 3 mm hardboard back tells you the maker is saving 4 euros per unit. An 8 mm or 12 mm back tells you they aren't.

Standard sizes you'll see on most catalogues:

• Base units: 60 cm deep, 72 to 90 cm tall, widths in 10 cm steps from 30 cm to 1.2 m
• Wall units: 30 to 40 cm deep, 60 cm to 1 m tall, same width steps
• Tall units: 2 to 2.4 m tall, 60 cm deep

The thickness of the panel itself is the other thing to look at. 18 mm is the honest standard. 15 mm is what you get at the bottom end of the market. 16 mm shows up in IKEA Metod boxes, which is one of those compromises that works fine in practice but tells you something about the unit cost.

Hardware-wise, you'll find cam locks (8 to 12 per box), wooden dowels (10 to 20), shelf supports (4 per shelf), and a hinge plate or two if it's a door cabinet. Hinges and runners are sold separately on most flat-pack kitchens, even the IKEA ones. Blum and Hettich are the names you want on the runners. Anything unbranded that says "soft close" on the bag and weighs less than 200 g per pair is going to wear out in three years.

The price ladder

A 60 cm base unit, in 2026, sits roughly here:

• Cheapest end (Wickes, B&Q, Bunnings own-label): 35 to 60 euros per box, melamine inside, foil-wrap door
• IKEA Metod: 70 to 90 euros for the box, doors and runners on top
• Howdens, Wren, the high street trade brands: 180 to 320 per unit including door and runners
• Made-to-measure flat pack from a smaller workshop: 150 to 280 per unit, sized to whatever width you ask for

A twelve-unit kitchen at the bottom end is genuinely under 1,000 euros for the boxes, and people do build them. The trade-off is that everything is exactly the size the manufacturer made it, and the kitchen wall is not. So you end up with two filler strips, a slightly squint corner, and a 4 cm gap behind the fridge that becomes a crumb collector for the next eight years.

The middle of the table, between IKEA and Howdens, is where most of the practical decisions get made. IKEA wins on price and finish-quality. Howdens wins on lead time if you're working with a fitter who buys from them anyway.

What "flat pack" hides about kitchen units

Three things, in particular.

One: the worktop is almost never flat pack. Even when the cabinets ship in boxes, the worktop arrives as a solid slab, cut to length, in a separate delivery. That changes the logistics. You can carry twelve flat-pack boxes up two flights of stairs. You cannot carry a 3.2 m laminate worktop up two flights of stairs without scuffing the wall, the worktop, or both.

Two: the install is not flat pack. Standing up the cabinets is the easy bit. The slow bit is fitting them to a wall that's 6 mm out of plumb, scribing the end panel to a chimney breast, drilling for the gas pipe, and notching the back of a wall unit around an electrical box. A motivated person can put up six boxes in an afternoon. The same person needs another two days to make the run actually look fitted.

Three: cheap kitchen units flat pack often skip the carcass shelves entirely. You get the box, the door, and a bag of pegs. You provide the shelf, and at 18 mm by 56.4 cm by 56.4 cm internal, it's not a panel you have lying around. So either you order shelves separately at 8 to 14 euros each, or you live with the empty box for a year and forget about it.

Where it actually breaks down

The cabinet itself almost never fails. What fails is the bit where the cabinet meets the room.

I've seen kitchens where the run is dead level for the first eight units and then climbs 1.2 cm over the last four because the floor sloped and nobody used a long spirit level. The doors don't line up. The drawers above the dishwasher won't sit flush with the ones beside them. None of that is the cabinet's fault. It's the install, but a flat-pack kitchen pushes the install onto the buyer or a fitter the buyer found on Marktplaats, and that's where the variance creeps in.

The other failure point is the corner unit. A standard corner cabinet is either 90 by 90 cm with a blind corner, or a 1 m L-shape with a carousel inside. Either way it's the fiddliest unit in the kitchen, and it's the one that turns up in the box looking least intuitive. Half the flat-pack kitchens I've seen had the corner unit assembled wrong on the first try.

When flat pack is the right call, and when it isn't

It's the right call when the wall is reasonably standard, when you're working to a tight budget, and when you've got either the time or the patience to do the install carefully. A 3 m straight run with a sink, a hob, an oven and four drawer units is a project a competent amateur can finish in a long weekend.

It stops being the right call the moment your kitchen has a sloped ceiling, a chimney breast, a wall that's clearly out of square, or a width that doesn't divide cleanly into 10 cm steps. At that point you're either spending more on filler strips and trim than you saved on the boxes, or you're commissioning something cut to fit, which is a different conversation.

If you're staring at an awkward wall and the standard widths leave you with a 7 cm gap that's going to bother you for ten years, that's the kind of thing knuslabs.com was built to take care of.

If you're planning the same kind of project, start with IKEA Pax alternative for exact-fit wardrobes or compare it with fitted wardrobe concepts from photos. For adjacent planning detail, read The flat pack bed frame, and why most of them rattle by year two and What you actually get when you order made to measure wardrobes.