Open-Plan Conversions Lewisham

GS Renovation creates open-plan spaces across Lewisham, turning the divided rooms of bay-fronted terraces in Forest Hill, Catford and Brockley into bright kitchen-diners and knock-through receptions. We handle the steelwork, the sign-off and the finishing so the space feels genuinely open.

In Lewisham, a knock-through finished as one room typically costs £3,000 to £8,000 or more, including the steel beam (indicative London ranges, MyBuilder and Checkatrade, 2026). GS Renovation Ltd, a building contractor based in Potters Bar, does the work in Lewisham: the structural engineer we appoint designs the steel, we install it, and building control signs it off.

How the job runs

1. Free site survey at your Lewisham address, covering the walls, services and floor levels, and an itemised quote.
2. The engineer we appoint sizes the beam, and the work is registered with Lewisham Council building control or an approved inspector. On a shared wall you serve the party wall notice as building owner; we supply the drawings.
3. Props in, opening cut, beam on padstones; then floors, heating and electrics are joined up.
4. Building control inspects the steel before it is covered. We finish the room, and the completion certificate follows.

Open-plan living in Lewisham's period homes

Lewisham's terraces were built as a series of small rooms, and the modern brief is to join them: a through-lounge across the two receptions, or a kitchen-diner formed by opening into the rear closet wing and side return. Around SE23 and SE26 near Forest Hill, these knock-throughs almost always cross a load-bearing wall, so the layout has to be engineered rather than simply demolished.

The structural engineer we appoint sizes a steel beam to carry the floors and masonry above, and we seat it onto padstones at each end. For broken-plan schemes we can frame the opening with slim Crittall-style glazed dividers that keep light flowing while separating the kitchen from the dining area, a look that suits the proportions of these SE-postcode homes well.

Housing in Lewisham

Count the homes in Lewisham and you get about 133,910: 45% built since 1945, 18% between the wars and 34% before 1919, with flats at 60% and houses at 40%. Where most homes are flats, opening up a flat in Lewisham changes the protected route from the bedrooms to the front door, so building control checks the escape before any wall comes out.

Open plan in Lewisham's post-war and newer flats

45% of Lewisham homes were built after 1945, and 17% in 2000 or later, so the room you want to open may well be in a post-war or recent building rather than a period house. In a post-war block the wall between kitchen and living room can be concrete or blockwork carrying the floor above, or a lightweight partition carrying nothing, and the building's drawings tell you which far more reliably than a knock test. For a Lewisham flat in a newer block, ask the managing agent for the structural drawings first. Where they exist they save opening up walls before the structural engineer we appoint has had a view.

The other constraint in a flat is the way out. The hallway is often the protected escape route from the bedrooms, which is why the kitchen door opens off it. Opening the kitchen to both the living room and the hall can remove that protection, so the design may need a sprinkler or mist system, a moved door, or a layout that keeps the hall closed. Where Lewisham is the building control body, its own inspectors check fire safety as well as structure, so in a Lewisham flat we settle the fire design with the structural engineer and the inspector before the wall comes down.

Steel, party wall and sign-off in Lewisham

Because the beam usually bears onto the party wall shared with the neighbour, an open-plan conversion in an SE4 or SE13 terrace is notifiable under the Party Wall Act, and you serve the notices before starting, as building owner or through your surveyor, using the drawings we give you. On site we install temporary propping, remove the wall in stages, set the steel and transfer the load in a controlled sequence so the house stays stable throughout.

The structural side is governed by the Building Regulations, so Lewisham Council's building control inspects the beam and its bearings and signs the work off. No planning permission is needed for internal work, even in a conservation area, but a listed home needs listed building consent. We coordinate the engineer, the steel and the finishing, then plaster and decorate so your new open-plan room is ready to use.

• Steel beam installation to remove the dividing wall
• Knock-throughs between front and rear reception rooms
• Lighting, heating and electrical reconfiguration

VOA Council Tax stock of properties, March 2025, for all 37 statistical areas in Lewisham. Counts rounded by the VOA.

People planning open-plan conversion in Lewisham may also want home renovation in Lewisham, our Lewisham area guide, builders in London, garage conversions, open-plan conversion across London and Kitchen Island Guide.

Why Lewisham Homeowners Choose GS Renovation

For open-plan conversions in Lewisham, GS Renovation delivers the whole job under one roof: steel designed by the engineer we appoint, the drawings for any party wall notice you serve on the neighbour, Lewisham building control sign-off, and a clean finish including Crittall dividers if you want broken-plan. We prop and stage the work safely in your occupied terrace and back it with our founder's 30+ years on the tools.

Reviewed jobs near Lewisham

1 MyBuilder review from Crofton Park, with each customer's own job title:

• Replace small section of wooden worktop, sink, tap and gas hob, Crofton Park, 17 Apr 2024 (5 out of 5)

Read all 31 on our reviews page.

Checked by Abdelaaziz Saaid, founder and director of GS Renovation Ltd (Companies House no. 14611254). Structural design is by the consulting engineer appointed to your project.