Steel beam installation, RSJ and structural alterations in Deptford. Trusted, professional, 30+ years' hands-on experience.
GS Renovation installs steel beams and RSJs across Deptford, from the Georgian and Regency townhouses off the high street to the SE8 warehouse conversions near the creek. With more than 30 years of structural experience, we remove load-bearing walls safely, working within the constraints of period and often listed buildings in Lewisham's conservation areas.

Many Deptford homes are solid-brick Georgian and Regency properties where the internal dividing walls carry real load. Before any wall comes out, our structural engineer calculates the beam size and specifies the padstones the RSJ will bear onto. We set up temporary propping, then carry out a staged, controlled demolition so the structure is never left unsupported. This measured approach matters in older SE8 houses where the masonry has settled over two centuries.
Because so many of these townhouses are listed or sit within a Lewisham conservation area, we treat original features with care, saving cornicing, joinery and fireplaces where the works allow. Every beam installation is notified to building control and signed off on completion, giving you the certificate you will need when you sell. Where the wall is shared with a neighbour, we also handle the Party Wall Act notices before work begins.
In Deptford's tightly packed terraces and townhouses, the wall you want to open is frequently a party wall shared with the house next door. Under the Party Wall Act you must serve formal notice on the adjoining owner before cutting a bearing into that wall or inserting a beam. You serve those notices, allow the statutory notice period, and coordinate with any surveyor the neighbour appoints so the project keeps moving.
The steelwork itself is only as good as its bearings. We form solid padstones at each end, usually in concrete or engineering brick, so the RSJ transfers its load cleanly into the existing masonry. On larger openings across a double reception or a kitchen knock-through, the engineer may specify a heavier universal beam or twin sections bolted together. We prop, install and case in the steel to the engineer's sizing, then leave it ready for plastering.
In a conversion or a lower-ground room, head height is the scarce commodity, and where the beam sits decides how much of it you keep. A downstand beam under the existing joists is the simplest and cheapest to build, but it drops the opening by the depth of the section plus its fire protection. In a room already tight under a Georgian first floor, that can be the difference between a comfortable space and a low one.
The alternatives are a shallower, heavier section, which keeps the drop down but costs more in steel, or setting the beam up between the joists with hangers so the ceiling runs through unbroken. The engineer will tell you which of those the structure allows. We measure the existing height, mark the proposed soffit on the wall in tape so you can see it, and agree the option before the steel is ordered, since a change afterwards means a new beam.
Deptford homeowners choose GS Renovation because we understand the quirks of solid-wall Georgian and listed properties, and we manage the whole process from engineer's calculations to building control sign-off. One team handles the propping, the steel, the padstones and any working cleanly in an occupied home and backed by more than three decades across Lewisham.
George was brilliant. Lovely bloke, very reasonably priced and a perfectionist to boot. He completed our small kitchen renovation with care and great…
George was a great find. The job required re-plastering the walls before fitting acrylic panels. He also re-plumbed the shower waste under the solid…
Saiid did a complete refurbishment of our small bathroom. This involved ripping out the existing bath/shower, basin, toilet, pipework, and tiles and…
FAQ
Location itself is not a line on our quotation. Two South East London homes of the same age and construction get similar RSJ and steel beam installation figures, and what separates them is condition and access at the SE8 address. GS Renovation does not charge Deptford homeowners a premium for the address, and there is no travel surcharge within Lewisham. The survey establishes the rest. Ring 07472 424 226 with the SE8 postcode and we will confirm before quoting. 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.
In most cases you can, and we plan the Deptford works around it. The question is whether RSJ and steel beam installation takes out the kitchen, the bathroom or the heating at your SE8 property for any length of time, and the programme shows exactly when. GS Renovation phases the Lewisham job room by room where staying put matters. Sometimes moving out for one week is simply easier. Ring 07472 424 226 and GS Renovation will describe how an SE8 household in Deptford usually manages.
Yes. Installations carry a five year guarantee, and GS Renovation is fully insured for every RSJ and steel beam installation project at an SE8 address. Alongside that you receive the Lewisham Council completion certificate for the structural work, which is the document that matters when a Deptford property changes hands. Aftercare goes through the same number you used during the job. Ring 07472 424 226 at any point afterwards in Lewisham. The guarantee and the certificate are both handed over at SE8.
The bearings and padstones before they are covered, and the beam itself against the engineer's calculations. Lewisham Council will want to see the steel in place and correctly supported at your Deptford property before it is boxed in, so the inspection has to be booked at the right moment.
Structure, services and previous work, in that order. On an RSJ and steel beam installation job in a listed and conservation-area Deptford home the unauthorised alteration by a previous owner is the commonest find at SE8, and it has to be resolved before Lewisham Council will sign anything off. GS Renovation deals with that as part of the job. You are told as soon as we find it. GS Renovation will explain how RSJ and steel beam installation handles an unauthorised SE8 alteration found on site.
Usually yes. Most Deptford terraces and townhouses share a party wall with the neighbouring property, and cutting a beam bearing into that wall triggers the Party Wall Act. You must serve written notice before starting. We prepare the notices, observe the statutory period and coordinate with the adjoining owner's surveyor, then install the steel onto proper padstones with building control sign-off.
Yes, and at no extra cost within Lewisham. GS Renovation covers Deptford and the SE8 area for RSJ and steel beam installation and much of the wider South East London besides. Distance only becomes a factor well beyond Catford, and we will say plainly if a property is too far. Email info@gsrenovationltd.co.uk with the postcode and we will book a free survey. Nothing is owed for the SE8 visit either way. Small jobs and full projects are treated on the same basis.
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 Deptford. Explore what else we do locally:
Same Service, Nearby Areas
We carry out RSJ and steel beam installation across Deptford and the surrounding areas. Explore a nearby location:
Free, no-obligation quote for RSJ and steel beam installation in Deptford. Rated 4.9 from 31 reviews on MyBuilder, fully insured, and building control handled for you.