A bathroom cabinet only works if it fits the space cleanly, opens without catching a tap or towel rail, and leaves you room to move. This guide walks you through measuring wall space, depth clearance and door swing step by step, so the cabinet you order is the cabinet that fits. Whether you are kitting out a compact ensuite or a family bathroom, you will finish knowing exactly which dimensions to shop by.
1. Why careful measuring matters
Bathrooms are the most obstacle-dense rooms in the house. In a couple of square metres you are working around a basin, taps, a mirror, a towel rail, a light switch, tiling, pipework and often a window or door. A cabinet that looks perfect online can foul on any one of these once it is on the wall. The difference between a satisfying fit and a costly return usually comes down to five minutes with a tape measure before you buy.
Getting it right also protects the things you cannot easily change. Return the wrong size and you have already drilled tile, run a bead of sealant, or lost the delivery window. Measuring first means you shop by numbers rather than by hope, and it makes browsing our bathroom cabinets far quicker because you can rule products in or out at a glance.
2. The tools you will need
You do not need anything specialist. A short, focused kit will give you accurate figures:
- A retractable steel tape measure (a 5m tape is ideal; avoid a fabric one, which sags and stretches).
- A pencil and a notepad, or your phone, to record every figure as you go.
- A small spirit level, or a level app, to check whether walls and floors are true.
- Low-tack masking tape to mark proposed edges on the wall.
- A stepladder if the cabinet will sit above head height.
Write down every measurement in centimetres and keep width, height and depth clearly labelled. Muddling the three is the single most common cause of an ill-fitting cabinet.
3. Measuring your wall width
Start with the horizontal space the cabinet will occupy. Measure the full width of the wall or recess, then measure again at the exact height the cabinet will sit, because skirting, tiling and pipe boxing can all narrow the usable gap at certain points. Note the tightest figure.
Next, decide how much breathing room you want on either side. A cabinet crammed edge to edge against a wall or shower screen looks cramped and is awkward to clean around. As a rule of thumb, leave at least 5cm of clear wall on any side that meets an obstruction, and more if a door or towel rail lives nearby. Deduct that clearance from your wall width to get your maximum cabinet width.
If you are pairing the cabinet with a basin or a wall mirror, sketch the arrangement roughly to scale. Lining a cabinet up with the basin below, or centring it under a mirror, looks far more considered than an off-centre guess. Our mirror buying guide covers proportioning the two together if you are buying both at once.
4. Depth and projection clearance
Depth is the dimension people forget, and it is the one most likely to cause daily irritation. A cabinet that projects too far will clip shoulders, snag towels, or block a light. Measure how far the cabinet can safely stick out from the finished wall without intruding into the space you actually use.
Pay particular attention to anything below or beside the cabinet. If it sits above a basin, check that its face does not overhang the taps in a way that makes them hard to reach. If it is near a doorway or the edge of a shower enclosure, make sure its projection does not narrow the walkway. In a compact room, a slimline cabinet of around 12 to 15cm deep often feels far more comfortable than a deep one, even though it holds a little less.
5. Door swing and opening clearance
A closed cabinet may fit beautifully and still be unusable if its doors cannot open freely. Hinged doors need arc clearance, so for each door work out the swing radius, which is roughly equal to the door’s width, and check that nothing sits inside that arc: a wall return, a window reveal, a light fitting, a towel ring or an adjacent cabinet.
A few practical points to weigh up:
- A single wide door needs a large clear arc on its opening side; two narrower doors halve the arc each one needs.
- Doors that open against a wall should stop short of it, or the handle and hinge will mark the paint or tile.
- Sliding doors and mirrored sliders need no swing clearance at all, which makes them the safest choice in a tight corner.
- If the cabinet sits above a basin, make sure an open door clears your head when you lean in.
Mark the fully open position on the wall with masking tape so you can see the real footprint before committing.
6. Height and eye-line placement
Mounting height decides how usable and how comfortable the cabinet feels. Over a basin, a common approach is to set the bottom of the cabinet so it sits a comfortable distance above the tap or splashback, keeping the mirror or main compartment near eye level for the household. Measure from the finished floor up to your planned bottom edge, then confirm the cabinet’s own height still leaves clearance above for the ceiling, coving or a light.
Think about who uses the room. A height that suits a tall adult may put the top shelf out of reach for others, so aim for a compromise the whole household can use. Also check the top of the cabinet against any downlight or extractor, and remember that a mirrored door reflects the ceiling, so a poorly placed light can glare.
7. Plumbing, sockets and obstacles
Before you settle on a position, map the hidden and fixed elements behind and around the wall. Concealed pipework and cables usually run vertically above and below taps and horizontally between fittings, so avoid drilling blind in those zones and use a detector where you can.
On the surface, note every fixed obstacle and its distance from your reference corner: the shaver socket, light switch, isolator, towel rail, window reveal and any tiling trim. A shaver socket is a frequent clash, as many people want a cabinet exactly where the socket already sits. If your chosen cabinet has an integrated socket or light, factor in the position of the existing supply too. Recording these distances now means you can check any product’s dimensions against a real, obstacle-aware space rather than an empty rectangle.
8. Matching the cabinet type to your space
Once you have your maximum width, depth and height, the type of cabinet almost chooses itself. Use the figures to narrow the field before you fall for a look. The table below shows how the main styles tend to behave in typical UK bathrooms.
| Cabinet type | Typical depth | Best for | Clearance to watch |
|---|---|---|---|
| Slimline wall cabinet | Around 12–15cm | Compact bathrooms and ensuites | Door swing in tight corners |
| Standard mirrored cabinet | Around 15–20cm | Storage above a basin | Projection over taps; head clearance |
| Double-door cabinet | Around 15–22cm | Family bathrooms, more storage | Two door arcs; wall width each side |
| Sliding-door cabinet | Around 14–18cm | Narrow walls with no swing room | Overall width only, no arc needed |
| Tall floor-standing unit | Around 20–30cm | Rooms with spare floor space | Footprint, walkway and door swing |
Depths are indicative and vary by product, so always shop by each cabinet’s listed dimensions rather than the category. If you are furnishing the wider space too, our full bathroom collection and the general how to choose a bathroom cabinet guide help you balance storage, style and finish once the size is settled. For any wall-mounted item, the same discipline applies, which is why our measuring furniture guide and the Will It Fit planner are worth a look before you order.
9. Buying with confidence
With your width, depth, height and door-swing figures written down, you can shop calmly and decisively. Compare them against each product’s dimensions, keep your clearances in hand, and you will know a cabinet fits before it arrives. When you are ready, browse our bathroom cabinets with fast tracked delivery, a 30-day returns window if you change your mind, and Klarna interest-free instalments to spread the cost. Take five minutes with a tape measure now, and the cabinet you choose will slot into place first time. Keeping your new unit looking its best is easy too, with tips in our furniture care guide.
Frequently asked questions
How much clearance should I leave around a bathroom cabinet?
Leave at least 5cm of clear wall on any side that meets an obstruction such as a shower screen, corner or towel rail. This keeps the cabinet from looking cramped, makes cleaning easier, and gives door handles room to move. Allow more where a door or another fitting sits close by.
What is a good depth for a bathroom cabinet in a small room?
A slimline cabinet of around 12 to 15cm deep usually feels most comfortable in a compact bathroom or ensuite. It projects less into the space, so it is less likely to catch shoulders or towels, while still holding everyday toiletries. Always check the individual product’s listed depth before buying.
How do I measure door swing for a hinged cabinet?
The swing arc is roughly equal to the width of the door. Measure the door’s width, then check that nothing sits within that radius on its opening side, such as a wall return, window reveal or light. Marking the fully open position on the wall with masking tape shows the real footprint.
At what height should a bathroom cabinet be mounted?
Over a basin, set the bottom edge a comfortable distance above the taps or splashback so the mirror or main compartment sits near eye level for the household. Measure from the finished floor to your planned bottom edge, then confirm there is still clearance above for the ceiling or any light.
Should I choose sliding or hinged cabinet doors?
Choose sliding doors when wall space is tight or a corner leaves no room for a door to swing, as they need no arc clearance. Hinged doors give fuller access to the shelves and suit walls with open space beside them. Match the door type to the clearance your wall actually offers.
How do I avoid drilling into a pipe or cable?
Concealed pipes and cables usually run vertically above and below taps and switches, and horizontally between fittings, so avoid those zones. Use a pipe and cable detector before drilling wherever possible, and note the position of any shaver socket or isolator that shares the wall.
Can a bathroom cabinet sit directly above the taps?
It can, provided its face does not overhang the taps in a way that makes them awkward to reach, and an open door clears your head as you lean into the basin. Check both the projection and the door swing at that height before committing to the position.
What measurements do I need before buying a bathroom cabinet?
You need four key figures: the usable wall width at the cabinet’s height, the safe projection depth from the finished wall, the mounting height from the floor, and the door-swing clearance. Record each in centimetres, along with the position of any socket, switch or rail, then shop by those numbers.
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