Under-Stair Space Planning Checklist

Stand under the stairs and note the point at which you can no longer stand upright, then the point at which you can no longer kneel.

Those two positions divide the wedge into the parts that can be used differently, and they are easy to mark today.

Look up at the underside of the stairs and record whether it is boxed in with a smooth soffit or left open with the treads visible.

An open underside changes everything about dust, appearance and what can be fixed where.

Mark where the outer edge of the staircase meets the floor and where any newel post lands, since both interrupt the opening.

The usable opening is almost always narrower than the space behind it, which is what defeats ready made furniture.

Record what the floor is like beneath the stairs, including any change in level, hatch or exposed surface.

The floor under a staircase is frequently unfinished, which affects what can be stored directly on it.

Take rough measurements at several points along the slope rather than one, and note that the shape is unlikely to be square anywhere.

A single measurement makes the space sound simpler than it is and leads to joinery that will not go in.

Work out which room or landing sits above the staircase, and whether sound from the stairs is noticeable underneath.

Footsteps overhead matter a great deal if the space is intended for working rather than storing.

List everything in the space that belongs to the building, including any meter, consumer unit, stopcock, wiring or pipework.

This inventory decides whether the space can be reworked at all, so it should come before any idea about its use.

Meters, isolators and stopcocks have to stay reachable in ways that only the relevant qualified trades and suppliers can set out.

Note any cable or pipe that crosses the space without obviously serving anything in it, and record it as a question for a professional.

Cables and pipes routed under a staircase are common and are exactly the thing joinery gets built over.

Nothing crossing this space should be moved, covered or disturbed except by the relevant qualified trade.

Empty the space if you can and list what actually comes out of it, separating what is used from what has simply accumulated.

Most under-stair projects gain more from what leaves the space than from what is built into it.

Record whether the vacuum cleaner, ironing board or drying rack lives here, since these bulky items need naming before shelves are designed.

Tall awkward objects are what under-stair cupboards are genuinely good at holding, and shelving removes that ability.

Open the existing door or panel and record what it clears in the hall, and whether it can be opened at all when someone is standing there.

The existing door already tells you what the hall can tolerate, which is useful information for any replacement.

Note whether the space feels damp, dusty or noticeably colder than the hall, and record it rather than explaining it.

These observations belong to the occupant and are what a professional needs in order to work out the cause.

Damp, cold or stale air in a closed off space has causes that only a qualified professional who can inspect it should name.

Decide whether the space is being asked to store things or to hold an activity such as working, washing or a cloakroom.

Storage and occupation make opposite demands on light, air and access, and mixing them satisfies neither.

If storage is the aim, list the specific items intended for it and note which are tall, which are heavy and which are needed daily.

The item list is what turns an under-stair cupboard into a design rather than a void with shelves in it.

If a working position is being considered, sit in the space and note where your head, your knees and a screen would actually be.

Sitting in the space for a while tells you more than a drawing can about whether working there is realistic.

If a small cloakroom is being considered, treat drainage, ventilation and headroom as questions for qualified professionals before anything else.

This use depends entirely on answers only professionals can give, so the questions should come before any layout.

Creating a cloakroom beneath a staircase raises drainage and headroom questions that only qualified professionals and the relevant local authority can answer.

Consider whether the space would be better left open to the hall, and note what the hall would gain or lose either way.

An open under-stair area can make a narrow hall feel wider while giving up the ability to hide anything.

Consider who would use the space and whether each of them can comfortably reach into a sloping void without help.

Under-stair storage is often used by whoever can crouch, which quietly excludes members of the household.

Decide whether the space would be entered from the front, from the side of the staircase or from the room behind it.

Side access along the slope reaches the deep end far better than a single opening at the front.

Weigh hinged doors against drawers or pull out units, and note what each would need to clear in the hall when open.

Pull out units bring the contents to you, while doors need someone to go in, and the hall may not allow either.

Mark on the floor what each proposed door or drawer would sweep, and check whether someone could still pass while it is open.

This is the check that most often changes an under-stair design, and it needs nothing more than tape and a clear floor.

Note how you would reach something at the far end of the wedge, and whether that requires crouching, kneeling or crawling.

If the retrieval method is unpleasant, the deep end becomes long term storage for things nobody wants.

Consider how the inside of the space would be lit and whether any light would need switching separately.

An unlit under-stair space is used by touch, which limits it to objects that can be identified by feel.

Any new lighting or electrical point in this space is a matter for a qualified electrician to assess and carry out.

Consider whether handles or catches would project into the hall, and whether people passing would catch on them.

In a narrow hall a projecting handle gets caught repeatedly in ordinary use, so it is worth deciding deliberately.

List the flat or thin things you own that could genuinely live in the narrowest part, such as boards, trays or folded items.

The taper suits a very specific set of objects, and naming them prevents it becoming a permanent void.

Consider whether anything kept at the narrow end would have to be slid past everything else to reach it.

If the narrow end can only be reached by unpacking the rest, it will be filled once and never revisited.

Consider deliberately leaving the narrowest part unused and closed off, and note what that would simplify in the joinery.

Accepting a small unused wedge often produces a better result than trying to claim every part of the shape.

Note whether the narrow end could be cleaned, since under-stair corners collect dust and are usually unreachable.

A part of the home that cannot be cleaned needs to be closed rather than open, which is a design decision.

Decide where heavy items would sit and ask a qualified professional what the floor and any joinery would need to carry them.

Weight tends to migrate to the deep end because it is the easiest place to put things down.

What any floor or fitted unit can support must be assessed by a qualified professional rather than assumed.

Photograph the empty space from several angles, including looking along the slope, and keep the images for the joiner.

Photographs of an empty wedge communicate its awkwardness far better than measurements alone do.

Ask a qualified professional what applies to the space beneath a staircase in this property, and confirm locally before any enclosure is planned.

This subject has to be settled before a design is worth developing, because the answer may change it entirely.

Anything relating to escape routes, alarms or fire safety beneath a staircase is for qualified professionals and the relevant local authority to determine.

Ask what should not be stored in an enclosed space under a staircase, and record the answer rather than deciding it from habit.

Households often store exactly what should not be there, simply because nobody has ever asked.

Ask how the services in the space would remain reachable after any enclosure, and who would need to reach them.

Meter readers, engineers and future occupants all need access that a finished cupboard can easily prevent.

Access arrangements for metering and service equipment must be confirmed with the relevant qualified trades and suppliers.

Ask a qualified professional what ventilation an enclosed under-stair space needs, particularly if anything damp would be kept there.

An enclosed wedge with no air movement is where wet coats and shoes cause problems that surface much later.

Whether an enclosed wedge under a staircase needs air moving through it is for a qualified professional to advise, and for the relevant local authority to confirm.

Ask whether anything may be fixed to the staircase itself, and treat the staircase as untouchable until you are told otherwise.

Joinery fixed to a stair is common in ready made solutions and is not something an owner should decide upon.

Whether anything may be fixed to a staircase or its supporting elements is for a qualified professional to assess.

Write down everything about this space that has to be confirmed locally, and keep it separate from the design ideas.

Keeping the confirmations separate stops them being quietly assumed as the drawings develop.

Draw the space as seen from the side, showing the slope, and mark on it every service and obstruction you found.

The side view is the drawing that describes an under-stair space, and owners rarely think to produce one.

Make clear that your figures are indicative, and agree at what point the maker will take their own set from the opening itself.

Very little under a staircase is square, so this space punishes small errors more than most others in the home.

Write down how you expect to use the space day to day, including who reaches into it and how often.

A joiner can design around a described habit, but not around a general wish for more storage.

Decide whether the joinery should read as part of the hall or as a separate object, and note which walls it would meet.

Under-stair joinery is seen from the whole hall, so its appearance is a hall decision rather than a cupboard one.

Work out how a finished unit would be brought into the hall, since anything made in one piece has to negotiate the front door.

Fitted units for awkward spaces are often assembled in place for exactly this reason, which is worth confirming.

Keep the confirmations you are waiting for in one list and share it with the joiner so nothing is drawn on an assumption.

Under-stair projects stall most often on an unanswered question that everyone assumed somebody else had asked.