How to Design a Curved Staircase That Works on Both Levels of an Open-Plan Home

Take the walls out of a house and something strange happens to the stairs. What used to sit quietly in a hallway, doing an unglamorous job nobody thought about, suddenly becomes an object in a room. Guests look at it while eating. Children run around it. Sunlight moves across it during the afternoon.

Then, having done all of that on the ground floor, the same structure has to arrive upstairs and behave in a completely different way.

That double life is the real design problem. Most advice treats a flight as one thing with one purpose, which works fine in a conventional layout. In an open plan it behaves more like two elements sharing a single set of drawings: a sculptural piece at low level, and a threshold plus an opening in the floor above. Reconciling the two is where projects either succeed or quietly disappoint.

Quick Answer: What Actually Changes?

A curved staircase in an open layout has nowhere to hide. Its outer face, its underside and its silhouette become permanent features of the living space, visible from almost every seating position. Above, the identical structure produces a void edge, a landing, and a balustrade run that reads as a boundary between the two floors rather than as decoration.

Choices that flatter the lower level frequently spoil the upper one. Guarding height is the clearest example: 900mm alongside the flight, 1100mm at the void, and a curve running between them.

Why Open-Plan Living Changes the Brief

Removing partitions does three separate things to a flight of stairs.

It exposes the underside permanently. In a hallway you almost never see the soffit. In a kitchen-dining-living space you see it from the sofa, the island, the table, constantly. Whatever finish you choose there becomes one of the most-viewed surfaces in the building.

It removes the acoustic buffer. Footfall carries. Conversation from above drifts down into the room without anything to stop it.

It removes the fire compartment. Those partitions were doing regulatory work that few homeowners realise, and taking them away has consequences discussed further down.

There is a fourth effect too, and it's subtler. Open layouts often lack a natural focal point once the fireplace has gone, so the stair inherits that role whether or not the design intended it. Curves handle this better than straight-run layouts, which is one reason architects reach for them so often in contemporary schemes. Our comparison of a curved versus straight staircase sets out the wider trade-offs.

One Flight, Two Viewpoints

Here is the approach I find most useful, and it's almost embarrassingly simple. Draw the thing twice. Once as the room below experiences it, once as the floor above does. The two drawings rarely agree, and settling the disagreement is the actual work.

What the Room Below Sees

Three surfaces dominate from ground level: the outer string, the soffit, and the outline of the guarding against whatever sits behind it.

Worth settling early:

• The outer face is an elevation. Treat it like cabinetry rather than a structural leftover. Painted timber, veneer and plastered soffits read very differently across five metres of open floor.

• Nosing shadows become a pattern. Viewed from a distance, that repeating rhythm turns graphic. Deep nosings emphasise it; flush ones calm it down.

• Orientation of the sweep matters. A flight curving its convex face toward the seating area feels welcoming. Turned the other way, it can look like the stair has shut you out.

• Under-stair space is exposed. What hides happily in a corridor becomes a visible design decision here. Commit to proper joinery or leave the area clear; half-measures look untidy.

One observation from site visits, for what it's worth: clients almost always underestimate how much soffit they will end up looking at. Design-stage photographs get taken from standing height, and nobody stands in their own living room.

What the Upper Landing Needs

Priorities invert once you're upstairs. Nobody admires an outer string from a landing. What registers instead is the edge of the opening, how much clear width you have when carrying something bulky, and whether the guarding feels solid under your hand.

Recurring problems:

1. A pinched arrival. Generous curves at low level can produce a mean landing above, because the void was drawn around the stair rather than around the circulation that has to pass it.

2. Guarding that walls things off. At 1100mm, a solid infill along the void can undo the openness the whole layout was meant to deliver. Glass balustrades tend to win here for exactly that reason.

3. Door swings clashing with the opening. Bedroom doors need clearance that early plans routinely forget.

4. A handrail that stops mid-air. Rails terminating awkwardly at the top of a flight, rather than continuing into the landing guarding, look unfinished and feel worse.

Resolving that last point usually means a continuous rail, which is a fabrication decision before it's an aesthetic one. Our explanation of what a continuous handrail is on a curved staircase covers why the joint-free version carries the cost it does.

Geometry: Rise, Going and the Walking Line

Regulations set outer limits. Comfort sits well inside them, and in a house where the flight is on permanent display, comfort tends to matter more than compliance alone.

For private domestic use in England and Wales, Approved Document K allows a maximum rise of 220mm, a minimum going of 220mm, and a pitch no steeper than 42 degrees, with twice the rise plus the going landing between 550mm and 700mm. Ireland's Technical Guidance Document K sets out equivalent provisions. Note that those two rise and going figures cannot simply be paired at their extremes, since the resulting angle breaches the pitch limit.

Element	Private Domestic Guidance	What It Means in an Open Layout
Maximum rise	220mm	Shallower risers lengthen the run, which can suit a long room
Minimum going	220mm	Measured along the walking line where treads taper
Maximum pitch	42 degrees	Target 33 to 38 degrees when the flight is a focal point
Headroom	2000mm above the pitch line	Check under the trimmer, not simply at mid-flight
Guarding beside the flight	900mm minimum	Height governs how much of the stair reads from below
Guarding at the void edge	1100mm	The single biggest influence on upstairs openness
Infill gaps	No 100mm sphere may pass	Applies to timber, metal and glass alike

That mismatch between 900mm and 1100mm is worth dwelling on. Managing the transition between the two heights, around a curve, is among the fiddlier details in this type of project, and it looks poor when rushed. Some designers hide it with a gradual ramp in the top rail. Others express it deliberately. Neither is wrong, though I'd argue the ramped version ages better.

Setting the Void Before the Flight

Order of operations decides most outcomes here. Establish the opening first, then the geometry, then the guarding. Reversing that sequence produces a staircase layout that fits the hole but not the house.

A workable order:

1. Mark the circulation you need upstairs, including door swings and any route for moving furniture.

2. Draw the void that circulation demands, keeping roughly 900mm of clear passage past the guarding.

3. Fit the sweep into that opening, checking the walking line rather than tread centres.

4. Test headroom at the tightest point.

5. Choose balustrade and handrail last, once both floors have stated what they need.

Footprint requirements vary a great deal by form. Our guide to how much space you need for a staircase gives typical dimensions, and the overview of types of curved staircases is worth reading before you settle on a single-radius design.

Fire Safety and Building Regulations in Ireland and the UK

People skip this section. Please don't; it reshapes budgets more than any finish choice.

In a conventional house, the enclosed hall and stair form a protected escape route. Take the walls away and that protection goes too, which matters under Approved Document B in England and Wales, and under TGD B in Ireland.

Broad principles, though every scheme needs individual assessment:

• Where a floor sits more than 4.5m above ground, guidance generally expects a protected stairway rather than an open one.

• In two-storey layouts where the flight discharges into open accommodation, one accepted route pairs a residential sprinkler system to BS 9251 with fire-resisting separation between floors.

• Cooking areas are normally expected to be separated from the wider space by fire-resisting construction. A kitchen sitting at the foot of an unenclosed run is the classic risk scenario.

• Interlinked smoke and heat detection is expected throughout, with heat detection serving the kitchen.

None of this rules out an open design. It does mean the fire strategy needs agreeing with building control early, rather than being found at inspection stage. Our curved staircases fire safety guide goes into more depth.

Some perspective on why the rules bite. RoSPA's Safer Stairs campaign reports that falls on stairs and steps kill over 1,000 people annually in England and Wales, with roughly 43,000 further hospital admissions, and estimates that building every flight to BS 5395-1:2010 would reduce the chance of falling by around 60% (RoSPA). Those figures cover all layouts. Still, a flight in constant view is a flight in constant use.

Sound, Heat and Daylight

Regulations govern sound between dwellings. Inside a single house you're largely on your own, and open planning makes the gap noticeable.

• Footfall: Hard treads above an open void behave a little like a drum skin. Solid timber on a laminated string is generally quieter than thin boards on a steel spine, and mass beneath helps further. Runners work, though they undercut the sculptural intention.

• Voices: An opening joins two acoustic volumes permanently. Nothing fixes this completely. Soft finishes upstairs help; positioning the landing away from the main seating zone helps more.

• Heat: Warm air rises through the void, cooling the room below while overheating the floor above. Underfloor heating compensates in part. Stratification in double-height spaces is real, and it belongs in a conversation with your mechanical engineer rather than your stair maker.

• Daylight: Better news here. Voids above a curved flight carry light from upper windows deep into the ground floor, and clear guarding keeps most of it. The choice between glass and metal balustrades counts for more in these homes than anywhere else, simply because that element occupies so much of the view.

Slightly contradictory advice follows, and I'll own it: glass keeps everything visually open, then shows every fingerprint in a house where the stairs sit beside a kitchen. Both statements are true. Most clients decide openness wins, and I think they're usually right.

Materials, Balustrade Choices and Fabrication

Material performs differently on each level, which is the theme running through all of this.

Material	From Below	From Above	Notes
Laminated timber	Warm, forgiving, sculptural	Quiet underfoot	Strong all-round choice for family use
Concrete with cladding	Solid and monolithic	Excellent acoustically	Longer programme; needs structural coordination early
Steel spine, timber treads	Slim and modern	Can transmit noise	Suits minimal interiors; detail the acoustics carefully
Glass guarding	Almost invisible, keeps daylight	Preserves openness at the void	Cleaning is the trade-off
Metal infill	Graphic and defining	Feels secure, adds privacy	Infill density changes the room significantly

Selection interacts with radius, span and budget in ways best discussed before drawings are frozen. Our comparison of timber, glass and metal for a bespoke curved flight covers the manufacturing side.

A sensible sequence for the whole process:

1. Settle the fire strategy with building control or a fire consultant.

2. Establish upper-floor movement and the opening it requires.

3. Fix the geometry against national guidance.

4. Resolve the soffit and outer face as visible surfaces, not afterthoughts.

5. Specify guarding and handrail once both levels have been tested.

Briefing your design team well at the outset saves considerable rework later. There's a useful checklist in our piece on what to tell your architect or interior designer before the process begins.

Frequently Asked Questions

Can a curved staircase be retrofitted into an existing open-plan house?

Often yes, though constraints tighten considerably. Retrofit work must respect the existing floor opening, and enlarging it means trimming joists or introducing steelwork, which requires building control notification. Fire strategy usually needs revisiting as well, since altering an escape route triggers fresh assessment under Approved Document B or Ireland's TGD B. Commission a structural survey before committing to any design. Floor-to-floor height and the position of load-bearing elements largely determine what is realistically achievable.

How wide should the flight be in a large open living space?

England and Wales set no fixed minimum width for private stairs, though 900mm to 1000mm is normal for a main flight, and generous schemes often reach 1100mm or more. Perception matters as much as measurement: something narrow can look mean when viewed across a big room, while excessive width consumes floor area fast. Measure the sightline distance from your primary seating position, then judge proportion from there rather than from plan drawings alone.

Does a curved design lose usable floor area compared with a straight one?

Broadly it occupies a similar area, distributed differently. Curves tend to leave more usable residual space at the base, because the footprint tapers rather than ending in a hard rectangle. Straight flights create a longer, narrower dead zone underneath. Where people use curved stairs as the principal route in an open layout, circulation generally passes around them more naturally, avoiding the corridor effect a straight run produces alongside a wall.

Is planning permission required for this kind of work?

Internal alterations rarely need planning permission in Ireland or the UK, but building regulations approval almost always applies. Protected structures and listed buildings are the exception, since internal work there frequently requires consent plus conservation officer input. Anything affecting the escape route, floor structure or ventilation must be notified to building control regardless of planning status. Confirm the position with your local authority early, particularly in period properties where original fabric is involved.

How long does a bespoke curved flight take to design and install?

Allow several months from first brief to installation. Design development, structural coordination and regulatory sign-off usually fill the early weeks, followed by manufacturing that varies with material and complexity. Laminated curves and continuous handrails need template work that cannot be rushed without quality suffering. Site sequencing matters too: fitting normally happens once the structural opening is complete, but before final finishes are applied to surrounding walls and floors.

Ready to Plan Yours?

Open layouts reward early decisions and punish late ones. Once the void has been cut, your options narrow quickly and expensively.

Bavari designs, manufactures and installs custom staircases across Ireland and the United Kingdom for private clients, architects and interior designers. Our team will review your project drawings, work through geometry and fire strategy with you, and give a clear picture of cost before anything structural gets committed.

Contact the Bavari sales team to arrange a consultation, or send us your plans for an initial assessment.