RSJ and Steel Beam Installation Southwark

GS Renovation installs RSJs and steel beams across Southwark, from the Victorian terraces of Peckham and Camberwell to the Georgian townhouses of Dulwich and the warehouse conversions of Bermondsey, as well as the post-war flats found across the borough. We remove load-bearing walls safely and see the work signed off by building control.

In Southwark, a steel beam for one opening typically costs £1,500 to £4,000 fitted and signed off, or £2,500 to £6,500 or more for a full knock-through with the engineer's fee and making good (indicative London ranges, MyBuilder and Checkatrade, 2026). GS Renovation Ltd, a building contractor based in Potters Bar, does the work in Southwark.

How the job runs

1. Free site survey at your Southwark address and an itemised quote.
2. The engineer we appoint sizes the beam, and the work is registered with Southwark 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 go in, the opening is cut and the beam is set on padstones, packed tight above.
4. Building control inspects the steel before it is covered. We make good, and the completion certificate follows.

Steel beams for Southwark period homes

Most steel beam jobs in Southwark involve opening up the ground floor of a Victorian or Georgian terrace in SE5 or SE15, where the wall between the front and rear reception rooms carries the floors and often a chimney stack above. The structural engineer we appoint sizes the beam to the actual loads, we prop the structure temporarily, then carry out staged demolition so nothing is left unsupported. The beam bears onto padstones calculated for the masonry.

Because Southwark terraces share dividing walls and chimney breasts with the house next door, most of these projects fall under the Party Wall Act. You serve the notices on adjoining owners as building owner (or your surveyor does) in good time, whether you are in a Peckham terrace or a Dulwich townhouse near Dulwich Park, and we give you the drawings they need and build to any award. Everything is inspected and signed off by building control, so when you come to sell, the paperwork on the structural alteration is complete and correct.

Housing in Southwark

Southwark has around 149,990 homes on the Council Tax list: 64% post-war, 7% interwar and 25% predate 1919, with 81% flats and 19% houses. Most homes here are flats, and a beam in a leasehold flat in Southwark needs the freeholder's licence for alterations, since the lease usually keeps the structure with the freeholder.

Southwark steel where the wall is post-war rather than Victorian

64% of homes in Southwark were built after 1945, against 25% before 1919. So a new beam in Southwark is more likely to be going into a post-war building than a Victorian one, and post-war walls are a different problem. Concrete crosswalls, concrete frames and precast floor planks are a different problem from old brick, and a padstone bedded on the wall is not always the answer there. The structural engineer we appoint may call for steel angles resin anchored into concrete, or a new post taken down to its own pad foundation, instead of a conventional bearing. Find out which construction you have before comparing quotes, because the two jobs are priced on different work.

That changes the paperwork as much as the method. Southwark Council's online form lets applicants begin a building regulations application as a building notice, full plans or regularisation. In a post-war block, the managing agent or the freeholder's surveyor may ask to see the design before granting a licence to alter, and full plans approval hands them calculations already checked by building control. It also settles the inspector's questions about fixings into concrete on paper, before anyone drills. Under a building notice nothing is approved in advance, so those questions can wait until the steel is on site, which in a block with a booked lift and neighbours on every side is the worst moment to have them.

Load-bearing wall removal in Southwark conversions

Steel work in Southwark is not limited to houses. In the warehouse conversions around Bermondsey and Borough, and in mansion flats across SE1 and SE16, structural change is possible but tightly controlled. Many of these are leasehold, so before any beam goes in you usually need the freeholder's licence to alter and coordination with the managing agent. We work within building-management rules and the sound insulation standards that apply between flats.

For houses, the process is more straightforward but no less careful. We handle knock-throughs between kitchens and rear rooms, chimney breast removals that need a steel beam, or gallows brackets only where the engineer and building control accept them, and full-width openings for rear extensions. On the older Georgian and listed stock in Dulwich and Camberwell, we take extra care with lime mortar, original joists and lath and plaster, keeping the character of the property intact while the new steel does the structural job quietly behind the finishes.

Hot works and why we prefer bolts

Welding inside an occupied house is something we avoid where the design allows. A welded connection produces sparks, heat and fumes next to timber joists, old lath and plaster and a century of dust in the floor void, and the fire risk continues after the work stops. Where hot works are unavoidable, they run under a permit with the area cleared and screened, an extinguisher to hand and a fire watch kept for a period afterwards.

The alternative is usually straightforward. Most connections in a Southwark house, whether beam to beam, beam to column or a splice in a section brought in in two pieces, can be designed as bolted joints and fabricated in a workshop where the welding is done properly and inspected. It arrives ready to assemble. That means less risk, less smell through the house, and a connection whose quality does not depend on conditions in a cramped opening.

• Access and lifting plans for restricted terraced and town-centre sites
• Building control applications and inspection sign-off
• Load-bearing wall removal and knock-throughs

VOA Council Tax stock of properties, March 2025, for all 34 statistical areas in Southwark. Counts rounded by the VOA.

Work in Southwark rarely sits on its own, so you may also want home renovation in Southwark, our Southwark area guide, London builders who fit steel, the Party Wall Act when a beam bears on a shared wall, RSJ and steel beam installation anywhere in London and Knock-Through Guide.

Trusted RSJ and Steel Beam Installation in Southwark

Southwark homeowners choose GS Renovation because we combine engineer-led steel design with our founder's 30+ years of hands-on structural work. We manage the propping, the padstones and the building control sign-off as one accountable job, working cleanly in occupied period homes and staying within the leasehold rules that govern the borough's conversions.

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.