Steel beam installation, rsj and structural alterations in Marylebone. Trusted, professional, 30+ years' hands-on experience.
GS Renovation installs steel beams and RSJs across Marylebone, from the red-brick mansion blocks off the main streets to the purpose-built period flats of W1. With more than 30 years of experience working inside Westminster's leasehold buildings, we open up load-bearing walls safely, with a structural engineer's calculations and full building control sign-off.

Removing an internal wall in a Marylebone mansion flat is rarely a simple knock-through. These purpose-built period blocks carry loads down through a stack of flats, so a wall on your floor may be supporting the flats above. We commission a structural engineer to calculate the beam, specify the padstones it bears onto and confirm the temporary propping needed while the wall comes down in controlled stages.
Because almost every flat in W1 is leasehold, the steelwork also has to satisfy the freeholder and their managing agent before a single prop goes up. We prepare the drawings and method statement that a licence to alter usually demands, coordinate access and noisy-works hours with the building management, and keep the block's other residents informed so the job runs without friction.
In a Marylebone block the wall or floor you are altering is frequently a party structure shared with a neighbouring flat, which brings the Party Wall Act into play. We help you serve the correct notices on adjoining leaseholders, allow for their response period and work to the agreed award, so the steel goes in without a dispute stalling the project or souring relations in the block.
Every beam we fit is signed off under building regulations, not planning permission, since this is internal structural work. Westminster City Council's building control, or an approved inspector, checks the engineer's design, inspects the bearings and propping and issues the completion certificate. That certificate is the document your freeholder, and any future buyer's solicitor, will expect to see on file.
Marylebone owners choose GS Renovation because we understand the leasehold and party structure realities of W1, not just the steelwork. We handle the engineer's design, the licence to alter paperwork, party wall notices and building control as one coordinated job, and our 30+ years across Westminster mean we prop, cut and beam in occupied blocks cleanly and safely.
George was brilliant. Lovely bloke, very reasonably priced and a perfectionist to boot. He completed our small kitchen renovation with care and great attention to detail. I've already recommended him to others.
Splendid job on our new kitchen refurb, including new flooring, moving the services, installing RSJ and preparing space for new back doors… George was always friendly, communicative and has an excellent attention to detail, ensuring everything is finished to a high standard.
Giorgio is an excellent and intelligent workman, and with very reasonable prices!… He paid a lot of attention to detail that is not common at all, and the final result was immaculate. Highly recommended!
FAQ
We price each Marylebone project individually, because the cost of RSJ and steel beam installation depends on far more than floor area. After a free survey you receive a clear written breakdown with no hidden extras. Call 07472 424 226 or email info@gsrenovationltd.co.uk. 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.
A straightforward Marylebone project can be done in a couple of weeks, while a larger RSJ and steel beam installation with structural work runs longer. We set out a realistic, stage-by-stage programme before we begin so there are no surprises.
Because we manage every trade in-house, your Marylebone project stays consistent and accountable from first fix to finish. Add transparent pricing, full insurance and real aftercare, and it is easy to see why Marylebone clients recommend us.
Removing a load-bearing wall in Marylebone does not normally need planning permission, but it always needs building regulations approval, a structural engineer's calculations and building control sign-off. Where the wall is shared with a neighbour, the Party Wall Act may also apply. We manage all of it.
Yes. A large share of Marylebone's homes are mansion-block and period-flat properties, and we renovate them regularly. We plan each RSJ and steel beam installation around their particular characteristics, such as leasehold consents, shared structure and sound insulation between flats, so the result suits the building and meets building control.
Often yes, but it needs care. In these period blocks the wall may be load-bearing and shared as a party structure, so we need a structural engineer to size a steel beam, the freeholder's licence to alter, likely a party wall notice, and building control sign-off. We manage all four so the opening is done legally and safely.
Yes. We work throughout Marylebone and the W1 area, as well as the surrounding parts of Central London. Contact us on 07472 424 226 to confirm we cover your street.
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 Marylebone. Explore what else we do locally:
Safe load-bearing wall removal with steel beam support.
Structural alterations, new openings and steel support.
Chimney breast removal with gallows bracket or beam support.
Open-plan kitchen, diner and living conversions.
Single and double storey extensions.
Full refurbishments and whole-house renovations.
Bespoke kitchen design and installation.
Luxury bathroom and wet-room refurbishment.
Same Service, Nearby Areas
We carry out RSJ and steel beam installation across Marylebone and the surrounding areas. Explore a nearby location:
Contact GS Renovation today for a free, no-obligation quote for RSJ and steel beam installation in Marylebone.
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