Key Takeaways
- Open-plan maximises light and sociability but offers little separation or sound control.
- Broken-plan keeps the openness while zoning space with partial dividers rather than walls.
- The structural work for a 4m open-plan opening with an RSJ costs £2,400 to £3,000 (MyJobQuote, 2026). All in, with engineer, Building Control and making good, an open-plan conversion runs £3,000 to £8,000+ (MyBuilder and Checkatrade, 2026).
- Open-plan on a three-storey house hits Approved Document B, and the fix is usually sprinklers plus fire-resisting separation.
- Part E imposes no acoustic duty at all once the wall is gone, so the noise problem is real and entirely yours to solve.
Open-plan living reshaped the London ground floor, and broken-plan is the correction that keeps the light while giving you somewhere to shut a door. Both are buildable in a terrace. The difference in cost is smaller than people expect, and the difference in daily life is larger.
Open-plan living
Open-plan removes internal walls to create one large, light-filled, sociable space, usually a kitchen-diner-living area. It is still what most people want: Houzz UK's kitchen studies found 45% of renovating homeowners made the kitchen more open to nearby rooms and a third went completely open-plan, and half are still enlarging the room. Claims that open-plan is over are largely imported American commentary with no UK data behind them.
The downsides are consistent and predictable: noise with nowhere for it to go, cooking smells through the whole floor, a larger volume to heat, and no quiet room. A utility room solves a surprising amount of it.
Broken-plan living
Broken-plan keeps the openness and light but zones the space with partial dividers: crittall glazed screens, half-walls, changes in level, pocket doors, freestanding units and joinery. The term was popularised in the UK by Houzz in 2016 and has since become the default brief from anyone who has lived with open-plan and worked from home in it.
The practical appeal is that a glazed screen stops sound and smell without stopping light, and a pocket door lets one room be two on a Tuesday and one on a Saturday.
Which suits you?
| Priority | Open-plan | Broken-plan |
|---|---|---|
| Light and flow | Maximum | High |
| Separation and quiet | Limited | Better |
| Sociability | Excellent | Very good |
| Working from home | Poor | Good |
| Flexibility | Lower | Higher |
| Cost | Structural work only | Structural work plus screens and joinery |
What does opening up cost in London?
The wall is the cheap part; the fees around it are not. Expect £2,400 to £3,000 for the structural work alone on a 4m open-plan opening in a load-bearing wall, and £3,000 to £8,000+ for a complete open-plan conversion once the engineer, Building Control and making good are added. Note that London and the South East run 20% to 40% above northern UK rates.
| Item | Typical cost, 2026 |
|---|---|
| Load-bearing wall removal, 2m doorway | £1,250 to £1,750 |
| Load-bearing wall removal, 4m open-plan opening, structural work only | £2,400 to £3,000 |
| Steel beam, supply only, 4m span | £900 to £1,280 |
| Steel beam supplied, installed on padstones and signed off, one opening | £1,500 to £4,000 |
| Structural engineer's calculations, single beam | £300 to £700 |
| Building Control application | £300 to £900 |
| Party wall surveyor, single agreed surveyor | £900 to £2,700 |
| Crittall-style glazed screen | from around £600 per m² |
| Pocket door, installed | £400 to £2,700, typically around £1,500 |
In a terrace or semi, bearing a new beam into the party wall is notifiable under the Party Wall etc. Act 1996, which is why London jobs carry costs that a detached house does not. See our guide to RSJ installation and removing a load-bearing wall and the Party Wall Act explained.
The regulations nobody mentions
Three bite, and only one of them is about structure. Fire is the serious one. Under Approved Document B, an open-plan ground floor that removes the protected escape route becomes a problem once you have a storey above 4.5m, typically a loft conversion or third storey. The compliant alternative to enclosing the stair is all three of: sprinkler protection to the open-plan areas, fire-resisting construction separating the ground storey from the upper storeys, and separating the cooking facilities from the open-plan area. Every dwelling also needs interlinked mains alarms with battery backup, and escape windows need a clear opening of at least 0.33m², no dimension under 450mm, with the opening no more than 1100mm above floor level.
Extraction is the one that ruins the cooking-smell argument. Approved Document F asks for 30 litres per second from a cooker hood ducted outside, or 60 litres per second from an extract fan sited elsewhere in the kitchen. A recirculating hood is not extract ventilation and does not count, so the fashionable recirculating island hood still leaves you needing a separate 60 l/s extract fan, and it does little for odour.
Sound is the surprise. Part E sets a 40 dB standard for internal walls, but it does not apply to a wall containing a door, and once you remove the wall there is no element left to regulate. The acoustic problem in an open-plan room is entirely real and entirely unregulated, which means soft finishes, an acoustic ceiling treatment or a broken-plan screen are the only answers. See building regulations explained.
Source: Approved Documents B, E and F, 2019 to 2022 editions with amendments.Getting it right
Go fully open-plan if your ground floor is narrow and light-starved, if the household is small or the children are young, and if there is another room in the house that can close. A London terrace rear that gains light from both ends feels like a different house. Go broken-plan if anyone works from home, if you have teenagers, if you cook seriously, or if this would be your last separate room. The rule we apply on site is simple: never remove your only closable room to gain a bigger one.
Be sceptical of value claims either way. There is no credible London data showing open-plan sells for more or less than a separate kitchen, and anyone quoting a percentage is guessing. Build for how you live. GS Renovation plans the layout and builds both across London and the surrounding counties, including open-plan conversions and load-bearing wall removal. For a free design consultation, contact us or call 07472 424 226.