Guide
Flat-pack or rigid kitchen: what is the difference?
A rigid kitchen arrives with its cabinets already built and glued in a factory, while a flat-pack kitchen arrives in boxes and is assembled on site. Rigid units are usually stiffer and quicker to fit; flat-pack units cost less to buy and are easier to carry in, but take longer to build and fit. Both can last well if they are fitted carefully.
What is a rigid kitchen?
A rigid, or pre-assembled, kitchen has carcasses built in the factory, usually glued and dowelled, with the back panel and drawer runners already fitted. They arrive ready to be fixed in place. Rigid units are common in mid-range and premium kitchens and in trade ranges sold through kitchen suppliers.
Because the joints are glued under factory conditions, rigid carcasses tend to be square and stiff, which helps doors line up and worktops sit flat. They are bulkier to deliver and need clear access: tall larder units need room to turn through hallways and up stairs, which can be tight in flats and narrow terraces.
What is a flat-pack kitchen?
A flat-pack kitchen arrives as boxes of panels, fixings and instructions. Each carcass is assembled on site, using cam fixings or dowels, before it is fixed in position. Flat-pack ranges are widely sold through home-improvement retailers and online, and some are well engineered, with solid backs and good hinges and drawer systems.
Assembly is precise work. Panels must go together square, back panels must be fully seated, and every fixing tightened correctly, or doors will not line up later. Building a whole kitchen's worth of units takes time and space, usually a clear room or garage to work in.
How do flat-pack and rigid kitchens compare?
The difference in day-to-day use is often smaller than people expect. What matters most is the quality of the carcass material, the hinges and drawer runners, and how carefully the kitchen is fitted. These are the main practical differences to weigh up:
- Purchase price: flat-pack is usually cheaper unit for unit
- Fitting cost: flat-pack costs more to fit because of the assembly time
- Time on site: rigid kitchens go in more quickly
- Strength: rigid carcasses are generally stiffer, though good flat-pack is solid once fixed
- Delivery: flat-pack boxes are easier to carry into flats and narrow houses
- Choice: both come in most door styles, from handleless to shaker
What does each type cost to fit?
Fitting a rigid kitchen bought elsewhere is typically £1,500–£2,500 for a small kitchen, £2,500–£3,500 for a medium one and £3,500–£4,500 for a large one, including VAT. A flat-pack kitchen built and fitted is typically £1,800–£3,000 small, £2,800–£4,200 medium and £4,000–£5,500 large, because the assembly is added to the fitting.
These are national guide ranges, confirmed after a survey visit. They cover units, doors, laminate worktops and panels; electrics, plumbing, stone worktops, tiling and flooring are priced separately. Build the assembly cost into any comparison, as a cheaper flat-pack kitchen can end up close to a rigid one once fitted.
Which type lasts longer?
A well-made rigid carcass with thicker panels and a solid back usually stands up to more years of heavy use, especially under heavy stone worktops. But a sound flat-pack kitchen that has been assembled square, fixed to the wall, levelled and sealed properly can also last for many years. Water getting into the board around the sink and dishwasher ends more kitchens than carcass type does.
Whichever you choose, look at the details: panel thickness, the back panel, edging on cut panels, hinge and runner quality, and how easily the doors adjust. It is also worth asking whether replacement doors and parts are likely to be available in a few years' time.
What should you check before buying either?
Have the room surveyed before ordering. Check that the plan includes every filler, end panel, plinth, cornice, light rail and appliance door kit you need, and that tall units will fit under the ceiling once raised on their legs. For integrated appliances, check the housing sizes and ventilation gaps against the models you have chosen.
Do not open or assemble anything before the fit. Keep the boxes sealed and stored somewhere dry, as chipboard swells if it gets damp. Before fitting, we check the delivery against the plan and the delivery note, and anything missing or damaged is for the supplier to replace.
Can a flat-pack kitchen take a stone worktop?
Usually, yes. Quartz, granite and sintered stone are heavy, so what matters is that every base unit is assembled square, fixed to the wall and to its neighbours, and set level on its legs, so the stone is supported evenly along its length. Some flat-pack ranges use thinner panels, so check the maker's guidance on stone and add support where runs are long.
The stone is templated once the base units are fixed and fitted about one to two weeks later. A unit that rocks or twists under a heavy slab risks cracking it, which is why the base units are checked carefully before the template visit.
Which should you choose?
Choose rigid if you plan to stay for many years, want stone worktops, or want the shortest time on site. Choose flat-pack if the budget is tight, access is awkward, or the kitchen is for a rental or a home you are preparing to sell. In both cases, the care taken over levelling, fixing and sealing decides how the kitchen looks after years of use.
If you are unsure, the survey visit is a good time to ask. We fit both types, and we can talk through how your chosen range is built, what it will cost to fit, and whether any parts of the plan need changing before you place the order.
Questions
Can you fit a flat-pack kitchen I have already bought?
Yes. We fit flat-pack kitchens from any retailer or online supplier. The carcasses are built on site, then fitted just as a rigid kitchen would be. Leave the boxes sealed until fitting day so nothing goes missing, and keep the delivery note so any missing or damaged parts can be claimed from the supplier quickly.
Is a rigid kitchen worth the extra cost?
Often, for a kitchen you plan to keep for many years, particularly under stone worktops or in a busy family home. Rigid units are quicker to fit, which offsets part of the price difference. For a rental, a small kitchen or a tight budget, a good-quality flat-pack range fitted carefully is a sensible choice.
Should I assemble flat-pack units myself to save money?
You can, but it carries a risk. Units that are not perfectly square cause misaligned doors and uneven worktops, and correcting them means taking units apart. If you do assemble them, follow the instructions exactly, seat the back panels fully and label each unit. Many people find paying for assembly as part of the fit simpler.
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This guide is general information about kitchen fitting in the UK, not legal, tax, electrical or structural advice for your property. Rules differ between England, Wales, Scotland and Northern Ireland; check with your local authority or a qualified adviser before relying on it.