Buying Guides
L-Shaped Kitchen or U-Shaped: the 40% Storage Gap
By the Hill & May team
Updated 2026
Almost every British kitchen refit comes down to the same fork in the road: an L-shaped kitchen on two walls, or a U-shape on three. The showrooms answer it with mood boards. It is actually an arithmetic question, and you can settle it in ten minutes with a tape measure, because the two layouts differ by a predictable amount of run in any given room, and the second corner has a predictable cost.
This piece is the head-to-head. If you have not yet narrowed it down to these two, start with our kitchen layout ideas and come back.
The number that decides it is width, not floor area
A U-shape puts base units on three walls, so it eats two lots of unit depth out of the room’s width and leaves the rest as walkway.
Two 600mm runs facing each other take 1200mm. Approved Document M Volume 1 asks for a minimum 1200mm clear space in front of and between kitchen units in dwellings built to the M4(2) standard, which you can read in Approved Document M on gov.uk. Add the two together and the hard floor for a U-shape is 2.4m of internal width. At exactly 2.4m you have a compliant walkway and nothing else: no room to stand aside while someone passes, and an open dishwasher door blocks the lot.
That is why the practical minimum is nearer 3m, which is where our layout guide sets it. Between 2.4m and 3m a U-shape is possible and usually miserable. Below 2.4m it does not exist, and the choice is an L or a galley.
An L-shape has no such constraint. It takes 600mm out of the width once, so it works down to about 1.8m of clear width and leaves two walls entirely free.
The run-length arithmetic
Here is the part nobody does before signing a plan. Measure the room, then work out how many linear metres of base unit each layout actually gives you.
The formulas are simple. Call the back wall W and the side wall D, both in metres. An L-shape gives you W plus (D minus 0.6), because the side run starts where the back run ends. A U-shape gives you W plus twice (D minus 0.6).
Run it on three common British room sizes and the pattern holds:
| Room | L-shape run | U-shape run | Gain | Walkway in the U |
|---|---|---|---|---|
| 3.0m x 2.7m | 5.1m | 7.2m | +41% | 1.8m |
| 3.6m x 3.0m | 6.0m | 8.4m | +40% | 2.4m |
| 4.2m x 3.6m | 7.2m | 10.2m | +42% | 3.0m |
A U-shape buys you roughly 40% more run in the same footprint. That is four extra 600mm base units in a mid-sized room, and about 1.4m² more worktop.
The gap gets bigger once you subtract the appliances
The 40% figure understates it, and this is the argument that usually settles it for people who cook.
A sink takes about 600mm of run. A hob takes 600mm, or 900mm if you are fitting a range cooker, which our range cooker sizing guide goes into. A dishwasher takes another 600mm. Those come out of the total in both layouts, because they are the same appliances in the same kitchen.
Take the 3.6m by 3.0m room with a 600mm hob. Subtract 1.8m of fixed items from each:
- L-shape: 6.0m minus 1.8m leaves 4.2m of working worktop
- U-shape: 8.4m minus 1.8m leaves 6.6m of working worktop
That is 57% more usable surface, not 40%. Fixed costs come off both, so the layout with more run keeps proportionally more of it. If you have ever run out of somewhere to put a hot roasting tin down, that is the number you are feeling.
What the second corner actually costs
A U-shape has two internal corners instead of one, and a corner in base units is the least efficient storage in a kitchen. The run-length figures above already subtract 600mm per corner for the overlap, so that part is accounted for. What is not accounted for is reach.
A standard blind corner unit puts a chunk of its own volume behind the adjoining door, where you get to it by lying on the floor with a torch. The fix is mechanical: a carousel, a magic corner pull-out or a Le Mans style swing-out, all of which claw back most of that space. Our kitchen corner units guide covers which suits which corner, and how to organise kitchen storage has the manufacturer figures on how much a pull-out actually recovers.
Budget for two of those mechanisms if you go U-shaped, not one. The corner hardware is the item people leave out of the quote and then discover is not optional.
The second corner has a design cost too. It creates a second inside angle where a worktop must be joined, mitred or masoned, which matters if you are choosing a material where joins show. Our kitchen worktop calculator will give you the linear metres for either plan.
The wall you forget: doors, windows and radiators
This is where most U-shapes die, and it has nothing to do with dimensions.
A U-shape commits three of your four walls. Everything else in the room has to happen on the fourth: the door in from the hall, a back door to the garden, a radiator, and the table if it is a kitchen-diner. British kitchens in terraces and semis very often have a back door in a side wall and a window over the sink, which means one of the three legs is already spoken for.
Before you commit, walk the room and mark on the plan: every door swing, the window cill height and width, the radiator, the boiler, the gas meter, and where the soil stack runs. Then see whether three continuous runs survive. Often they do not, and what you actually have is an L-shape with a short return, which is a different thing and worth planning as one.
An L-shape leaves two full walls free. That is what makes it the default British layout: it takes the awkward services and puts them somewhere else. It also grows. A kitchen in L shape is the layout that most easily gains a peninsula or an island later, and our kitchen island ideas and breakfast bar ideas cover the width you need before that is realistic.
Plan in metres of run, not in units
One warning before you translate any of this into a shopping list. British kitchen unit dimensions are not as standard as the charts imply.
Magnet states plainly that its base units are 807mm high and 565mm deep, with widths from 150mm to 1000mm and 600mm the most common. Howdens names its ready-assembled base cabinets by their dimensions in the product title, in the form 720mm x 600mm x 575mm, which is carcass height, then width, then depth. Those are different numbers from different suppliers for the same nominal unit, because one includes the legs in the height and the other does not, and because carcass depth and worktop depth are not the same measurement.
The consequence for an L or a U is small on one run and compounding around a corner, where a 10mm difference in carcass depth shifts everything downstream of it. So plan the layout in metres of run and clear width, get the supplier’s own dimension sheet before you fix the positions of the sink and the hob, and treat any generic size chart, including ours in the kitchen cabinet sizes guide, as a planning approximation rather than a cutting list.
So which one
Choose a U-shape if the room is at least 3m wide, the fourth wall can carry the door and the traffic, you cook enough to want 6m of working worktop, and you are willing to pay for two lots of corner hardware. It is also the layout that shows a range cooker best, because the cooker can sit centred in the back run with a full wall of units either side.
Choose an L-shape if the room is under 3m wide, if a door or a back door interrupts a third wall, if you want a table in the room, or if you may add an island or peninsula later. You give up around 40% of the run and roughly a third of the working worktop, and you get back a lighter room, one corner instead of two, and options.
For most British kitchens under about 12m², with a back door in the wrong place, the L-shape is the right answer and the U-shape is the one people wish they had space for. Above 12m², with a clear fourth wall, that flips.
Frequently asked questions
What is the minimum room width for a U-shaped kitchen? 2.4m of internal width is the absolute floor, because two facing 600mm runs take 1200mm and Approved Document M asks for 1200mm of clear space between units. At exactly 2.4m an open appliance door blocks the walkway completely. Treat 3m as the width at which a U-shape becomes comfortable, and anything between the two as a compromise you should test with tape on the floor first.
How much more storage does a U-shaped kitchen give than an L-shape? About 40% more linear run in the same room, because the third leg is the same length as the second minus the corner overlap. In a 3.6m by 3.0m room that is 8.4m against 6.0m. Once you subtract the sink, hob and dishwasher, which take the same space in both, the gap in genuinely usable worktop widens to nearer 57%.
Is an L-shaped kitchen better for a small room? Usually, yes. An L-shape takes unit depth out of the room’s width once instead of twice, works down to about 1.8m of clear width, and leaves two walls free for a door, a window, a radiator and a table. It also has one corner to solve rather than two, which cuts both the cost and the amount of hard-to-reach storage.
Where should the sink go in an L-shaped kitchen? Under the window if there is one, which is where the plumbing usually already is, and on the longer of the two runs. Keep the dishwasher immediately beside it and the crockery cupboard above or next to that, since loading and unloading is the journey you make most often. Leave your longest clear stretch of worktop between the sink and the hob rather than beyond the hob.
Can you put a range cooker in an L-shaped kitchen? Yes, and it usually goes in the middle of the longer run rather than near the corner, so you keep worktop on both sides of it. Allow at least 300mm of landing space on each side, more if you can. Check the run length first: a 900mm or 1100mm range takes a serious bite out of a 6m total, which is one reason the U-shape suits big cookers better.
Does a U-shaped kitchen need two corner units? It needs two corner solutions, which is not quite the same thing. Each internal corner can be a carousel unit, a blind corner with a pull-out mechanism, or a diagonal unit, and one leg can end in a tall unit or an appliance housing instead so that only one true corner exists. What you should not do is fit two plain blind corners and hope, because that is roughly a square metre of storage you have paid for and cannot reach.
