A wardrobe can look perfectly straightforward until the tape measure comes out. A skirting board projects further than expected, the ceiling drops by a few millimetres, or one side wall is not quite square. Knowing how to measure wardrobe openings properly gives you a useful starting point for planning storage, whether you are considering sliding doors, hinged doors or a fully fitted interior.

For a bespoke installation, a professional survey is always the final authority. It accounts for the details that drawings and home measurements can miss. But measuring carefully before a design consultation helps you understand what is possible, compare ideas realistically and make better use of your appointment.

What you need before measuring a wardrobe opening

Use a good-quality metal tape measure, a pencil, paper and ideally a spirit level. A laser measure can be helpful for longer rooms, but it should not replace physical checks where walls, floors or ceilings may be uneven. Take photographs of the opening too, including the surrounding walls, floor and ceiling. They can reveal obstructions you may forget to note later.

Start with the opening cleared as far as possible. Move freestanding furniture, boxes and clothes rails out of the way so that you can reach the true edges. If an existing wardrobe is being replaced, measure its space rather than assuming the new furniture must follow its dimensions. A made-to-measure design may use the area more effectively.

Keep a simple sketch as you work. Label the left and right sides as you face the opening, then write every measurement in millimetres. Millimetres are the standard for fitted furniture and reduce the chance of confusion between, for example, 180.5 cm and 1,805 mm.

How to measure wardrobe openings for width

Measure the internal width of the opening in three places: at the top, through the middle and at floor level. Record all three figures. Do not simply use the largest measurement because it is the most appealing. The smallest width is often the critical one where furniture must fit between two walls.

For an alcove, place the end of the tape against the finished wall surface on one side and extend it to the finished surface on the other. Take care not to hook the tape over a protruding skirting board or picture rail unless that feature will remain and form part of the finished design.

If the walls are noticeably out of square, add a note showing which end is tighter. A difference of a few millimetres is common in older properties; a larger difference may affect how end panels, fillers and doors are designed. Bespoke fitted furniture is made to accommodate real rooms, but accurate information helps the designer plan a clean, zero-gap result.

Where there is only one return wall, such as an open wardrobe run along a bedroom wall, measure the total available wall length. Then identify the usable length separately. Radiators, sockets, door architraves, window boards and switches can reduce the practical furniture width even when there appears to be plenty of wall space.

Check for skirting boards and coving

Skirting boards are one of the most common reasons a measurement is misleading. Measure their height and projection from the wall, and note whether you intend to retain them. A fitted wardrobe may be scribed around existing skirting, set in front of it, or designed after it has been removed. Each approach changes the depth and finish of the installation.

Do the same for coving, ceiling roses, decorative beams and picture rails. A wardrobe that meets the ceiling can give a more integrated appearance and prevent dust collecting above it, but the ceiling line needs to be assessed rather than assumed to be level.

Measure the height at more than one point

Take the height from the finished floor to the ceiling at the left, centre and right of the opening. Write down the smallest height as well as the variation. Floors can slope, and ceilings can dip, particularly in period homes, loft conversions and rooms affected by previous alterations.

If you are measuring beneath a sloping ceiling, measure the height at several points along the proposed wardrobe width. Mark the distance of each point from the nearest wall on your sketch. A single height measurement does not tell a designer where the slope begins or how quickly it falls.

For wardrobes under stairs, record the full height at the tallest point, the lowest practical height and the horizontal distance between them. Also measure the depth available under the staircase. These spaces can become exceptionally useful storage, but internal layouts need to follow the angle rather than fight it.

Avoid measuring from carpet pile if a new floor is planned. The finished floor level matters. If carpet, underlay, laminate or tiles are due to be changed, tell the designer what is being removed and what is going in. A 10 mm change in floor level can matter when a wardrobe is fitted tightly between floor and ceiling.

Do not forget wardrobe depth and clearance

An opening may be wide and tall enough for a wardrobe, yet still lack the depth needed for the storage you want. Measure from the back wall to the front-most point where the wardrobe can finish. Take this measurement at both ends, particularly if a side wall is angled.

A conventional hanging rail needs enough internal depth for hangers and clothing to sit comfortably without doors catching. Sliding wardrobe systems generally require additional depth for the door tracks and overlapping panels. Hinged doors need clear floor space in front to open properly, while sliding doors save that swing space but only allow access to part of the wardrobe at one time.

This is where the best choice depends on the room. In a narrow bedroom, sliding doors may make everyday movement easier. In a deep alcove where full access matters, hinged doors can be a strong option. A design consultation should consider the bed position, drawers, bedside tables and the route around the room, not just the dimensions of the opening.

Measure the space in front of the wardrobe

Mark where the wardrobe front would sit, then measure the clear distance to the nearest obstruction. This might be a bed, chest of drawers, radiator or opposite wall. Also consider opening doors into the room. A bedroom door that clashes with a wardrobe door is inconvenient from the first day, even if the measurements technically work.

For sliding doors, check the position of light switches and sockets near the wardrobe front. For hinged doors, note handles, window boards and furniture that could restrict their opening. Small details such as these shape the final layout and can influence whether drawers, shelves or hanging sections belong in a particular area.

Record obstacles, services and awkward details

Do not measure only the empty rectangle. Look closely at everything within and around the wardrobe opening. Make a note of radiators and pipework, plug sockets, switches, internet points, loft hatches, smoke alarms, extractor controls, access panels and boxing around soil pipes.

Electrical points are not necessarily a reason to rule out fitted furniture. They may be incorporated into a design, moved by a qualified electrician or kept accessible through a planned panel. What matters is that they are identified early. Covering an essential switch or access point without a solution creates an avoidable problem.

Windows deserve similar attention. Measure the sill height, its projection from the wall and the distance from the window to the nearest corner. If curtains or blinds extend into the wardrobe area, note their brackets and how far they project. In alcoves beside a window, a shallow cupboard or shelving may suit the available space better than a full-depth hanging wardrobe.

Common measuring mistakes to avoid

The most frequent mistake is measuring only once. Three width and height measurements take very little extra time and give a far clearer picture of an uneven opening. Another is rounding measurements too generously. Record the exact figure shown on the tape, then let the design and installation team make the appropriate allowances.

It is also easy to measure brickwork or plaster where the finished room will be different. If you are mid-renovation, provide dimensions but clearly state what will change before installation. New flooring, replastering, boxing-in work and altered skirting can all affect the final opening.

Finally, do not deduct allowances for furniture yourself. Some homeowners try to leave a fitting gap, only to make the planned wardrobe unnecessarily smaller. A specialist will decide the correct tolerances, fillers and scribing required after surveying the room.

When home measurements are enough and when to arrange a survey

Your own measurements are ideal for an initial conversation, a rough budget discussion and exploring possible layouts. They are particularly useful when deciding whether a king-size bed, desk or dressing table can sit comfortably alongside new storage.

They are not a substitute for a final site survey. This is especially true for sloping ceilings, alcoves, older homes, newly plastered rooms and spaces with uneven walls or floors. A professional survey confirms finished dimensions, checks access for delivery and installation, and ensures the proposed doors and interiors will work in everyday use.

At Glide & Slide, that detailed approach is what turns a promising gap in a room into storage that looks built in from the start. Bring your sketch, measurements and photographs to the conversation, but leave the final tolerances to the people who will design and fit the furniture. The result should not merely fit the opening – it should make the whole room work harder.