RSJ and Steel Beam Installation Hendon

GS Renovation installs RSJs and steel beams throughout Hendon, from the 1930s semis off the main NW4 roads to the purpose-built blocks that hold most of Hendon's homes. We remove load-bearing walls safely and open up these homes for modern family living.

In Hendon, 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 Hendon.

How the job runs

1. Free site survey at your Hendon address and an itemised quote.
2. The engineer we appoint sizes the beam, and the work is registered with Barnet 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 beam design for Hendon interwar homes

Hendon's 1930s semis were built with solid or early cavity brick walls and a fairly compartmentalised layout, so almost any wall you want to lose between the front and back reception is doing structural work. Before we touch it, a structural engineer calculates the load and specifies the beam, whether that is a single RSJ or a goalpost frame, along with the padstones the ends bear onto.

We then set up temporary propping, take the wall down in careful stages, and lift the steel into position onto its padstones. Everything is checked and signed off by building control under the Building Regulations. On a typical Hendon semi the beam carries the floor above and, on the flank wall, part of the roof, so the padstone bearing has to be exactly as the engineer drew it.

Housing in Hendon

By the valuation list's count, Hendon holds about 16,060 homes, 38% houses and 62% flats; by age, 20% were built before 1919, 37% between the wars and 43% since 1945. Where most homes are flats, a beam in a leasehold flat in Hendon needs the freeholder's licence for alterations, since the lease usually keeps the structure with the freeholder.

Getting a steel beam into a Hendon flat through the common parts

62% of homes in Hendon are flats, and a beam for a flat has to travel through the building before it goes anywhere near the wall. The stair turns, the landing widths and the lift car set the longest length that can be carried in, and in a mansion block the tightest point may be a half landing. Measure the route before the design is finalised. A beam that cannot turn the stair either comes in through a window under a lifting plan or is made in two lengths bolted together, with a splice designed by the structural engineer we appoint.

The structure of the block matters too. 43% of homes in Hendon were built after 1945, and a flat in a post-war block may have concrete floors rather than timber joists. A wall under a concrete slab is taken out on props set to the slab, and the steel is fixed to the concrete with anchors chosen by the engineer. The bearings may land on concrete walls or columns that are scanned for reinforcement before they are drilled. Book the managing agent's approval for the lift, the protection and the delivery slot alongside the licence, so a delivered beam is never left standing in the entrance hall.

Party wall duties on shared Hendon walls

Because many Hendon houses are semis, the wall between you and your neighbour is often a shared party wall, and the chimney breasts and stacks often sit within it. Where your steelwork bears into or cuts into that wall, the Party Wall Act applies and you, as building owner, must serve your neighbour the correct notice before work starts. We flag this early and give you the drawings it needs, so the notice period does not hold up the build.

For a mid-terrace or an end-of-terrace property near Golders Green or Finchley the same principle holds on the adjoining flank. We coordinate the propping, the engineer's details and the notice timing so the structural opening proceeds cleanly. Getting the party wall paperwork right protects both households and keeps the project on programme rather than stalling at the demolition stage.

What happens in the floor above the beam

Fitting the steel is only half of what happens at ceiling level. The joists that were bearing on the wall have to be transferred onto the new beam, and how that is done depends on the engineer's detail. If the beam sits below them they simply rest on the top flange and are strapped. If it is raised into the floor zone to keep the ceiling flat, each joist is cut back and carried on a hanger bolted or welded to the web.

That work means the ceiling in the room, and sometimes a strip of the bedroom floor above, is opened up and reinstated. In a 1930s Hendon semi the ceiling below is often the original lath and plaster, which does not take kindly to being cut, so we usually plan to overboard and skim the whole ceiling rather than patch a strip that will always show. You are told which of those applies before we begin.

• Structural engineer's calculations arranged and followed
• Load-bearing wall removal and knock-throughs
• Temporary propping and staged, controlled demolition

VOA Council Tax stock of properties, March 2025, for Hendon Central, Hendon Park, North Hendon & Sunny Hill and West Hendon. Counts rounded by the VOA.

If this is your first project in Hendon, these are worth a look: home renovation in Hendon, RSJ and steel beam installation across Barnet, builders in Barnet, party walls and steel beams, our London RSJ and steel beam installation page and Architect or Structural Engineer?.

Why Hendon Homeowners Choose GS Renovation

Hendon homeowners choose GS Renovation because one team appoints the engineer who produces the calculations and manages the propping, the safe demolition and the building control sign-off. We understand how these 1930s semis and NW4 blocks of flats are built, we coordinate the work around the party wall award on shared walls, and our founder's 30+ years on the tools means the steel goes in right the first time.

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.