Steel beam installation, RSJ and structural alterations in Lewisham. Trusted, professional, 30+ years' hands-on experience.
GS Renovation installs RSJs and steel beams across Lewisham, from the bay-fronted Victorian terraces of Forest Hill in SE23 to the Edwardian family homes near Blackheath in SE13. With 30+ years of structural experience, we remove load-bearing walls safely, opening up the tight, cellular layouts typical of these period terraces while keeping the house sound.

The classic Lewisham job takes out the wall between the front and rear reception rooms, or the wall into the rear closet wing, to make a single open living space. Because these Victorian and Edwardian terraces carry floor and roof loads through those internal walls, a structural engineer sizes the steel beam first. We then set the RSJ onto concrete padstones at each end so the load spreads safely into the remaining brickwork.
Safe sequencing matters on an occupied street in SE4 or SE6. We install temporary props, Acrows and strongboys, to hold the structure above, then carry out staged demolition rather than pulling the wall down in one go. Once the beam is in and bearing correctly, we remove the props, fireproof and box in the steel, and make good. Lewisham Council building control inspects the work and signs it off, giving you the completion certificate you need.
Terraces in Deptford, New Cross and Catford share a party wall with the house next door, and the chimney breasts and stacks are often built into that shared wall. When your steel beam bears near or into it, the Party Wall etc. Act 1996 usually applies. That means serving formal notice on your neighbour before work starts, typically two months ahead, so the process is agreed and everyone is protected.
We are used to coordinating this across Lewisham's tightly packed streets. Where a chimney breast is removed on a lower floor, the stack above must be properly supported with a gallows bracket or beam, again to the engineer's design. We can recommend a party wall surveyor, prepare the technical drawings your neighbour's side will want to see, and time the notice period so it does not hold up the rest of your build.
Lewisham homeowners choose GS Renovation because we handle the whole structural job under one roof, from the engineer's calculations to the propping, the beam and building control sign-off. With 30+ years opening up SE13, SE23 and SE26 terraces, we work cleanly in occupied homes and stand behind every beam we install.
Giorgio is an excellent and intelligent workman, and with very reasonable prices! He installed a kitchen extractor fan in a complicated situation…
He was very very good. He just got on with the job and we was beey pleased with the result. He Also cleaned everything away when he finished. Will…
Very friendly and I am very pleased with the work he has done, also very clean worker and enthusiastic about his work. Can not fault this company!!!!…
FAQ
It compares well, mainly because there is no head office to fund. GS Renovation is the contractor doing the RSJ and steel beam installation work at your SE4 property, not a broker passing a Lewisham job on with a margin added. You deal with the people on site, and the quotation shows the Lewisham Council element rather than an administration fee. Compare the scope, not just the total. Ring 07472 424 226 and GS Renovation will go through the SE4 lines with you. As a rough guide, RSJ and steel beam installation in London runs roughly £1,500 to £4,000 for the beam itself on a single straightforward opening, covering supply, installation and building control sign-off; a full knock-through including taking the wall out, the structural engineer's fee and making good more typically comes to £2,500 to £6,500 or more (indicative London ranges, MyBuilder and Checkatrade, 2026). Your figure depends on the size, specification and condition of the property, which is why we survey before quoting.
It changes it substantially. Lewisham contains Victorian terraces, interwar semis, post war houses and blocks of flats, and the floor construction and wall build up differ across all of them. A beam bearing into solid brickwork is a different detail from one bearing into a cavity wall or connecting to a concrete frame. The engineer designs from what the building actually is.
It changes both the propping and the connection. Where your Lewisham property has concrete floors, the load arriving at a new beam is greater than from a timber floor and the temporary support has to suit. Fixing into concrete also differs from building into brickwork, and the engineer specifies the connection detail. None of it is unusual, but none of it is the same as a timber floored terrace.
Yes, with the design accounting for the floor as shared structure. In your Lewisham flat the floor being cut for a bearing is also the ceiling of the home below, and it provides fire and sound separation for both. The engineer designs the bearing and the trimming accordingly, the separation is reinstated, and the freeholder's licence is obtained alongside building control approval.
Whatever the lease, the managing agent and the council's rules on construction noise allow, and those are established first. Noisy work in a Lewisham building affects every other home in it, so percussive activity is concentrated into agreed periods rather than spread across the day. Neighbours are told in advance what will happen and roughly when. That costs nothing and prevents most complaints.
Who provides it, where it stands and how often it goes. On a Lewisham job a skip on the public highway needs a licence from the highway authority with lighting and markings, while a driveway or forecourt avoids that entirely. Where neither is available, bagged waste on scheduled collections is used instead. The arrangement is settled before the start date rather than on the first morning.
Every Service, One Team
The same trusted team, 30+ years' hands-on experience and free, no-obligation quotes apply to every GS Renovation service in Lewisham. Explore what else we do locally:
Same Service, Nearby Areas
We carry out RSJ and steel beam installation across Lewisham and the surrounding areas. Explore a nearby location:
Free, no-obligation quote for RSJ and steel beam installation in Lewisham. Rated 4.9 from 31 reviews on MyBuilder, fully insured, and building control handled for you.