Structural alterations, new openings and steel support in New Barnet. Trusted, professional, 30+ years' hands-on experience.
GS Renovation carries out structural alterations across New Barnet, in the Victorian terraces near Victoria Recreation Ground and the interwar semis beyond them. New supported openings, replacement joists, new lintels over widened openings and repairs where an original timber lintel has rotted in the wall. Every alteration is designed by a structural engineer we appoint and inspected by Barnet Council building control.

Victorian terraces in New Barnet hide a predictable set of problems, and the first day of opening up usually finds two or three of them. Timber lintels over internal openings that have shrunk away from the brickwork above. Lath and plaster on the first floor partitions, which will not hold a fixing and comes off in sheets. Suspended timber ground floors on honeycomb sleeper walls, with airbricks that a later patio has buried. None of that stops the work, but it changes the sequence and it changes the price if nobody looked first.
Joist ends are the other regular find. In an EN4 terrace the floor joists bear into pockets in the party walls, and where a gutter has been overflowing for years the ends nearest that wall are soft. Replacing them means either new joists to the engineer's size or new bearing on a wall plate bolted to the masonry. We cut back to sound timber, treat what stays, deal with the gutter that caused it, and never pack a rotten joist end up on a bit of slate to make the floor look level.
Structural alteration inside your house is controlled under the Building Regulations rather than planning, so it is Barnet Council building control, or an approved inspector, that reviews the calculations and inspects the work. Planning only enters the picture for external change. The engineer produces the design; we build to it and we do not alter it on site. Where an alteration turns out to need more than the drawing anticipated, which happens once the plaster is off, the engineer comes back and reissues rather than us making a judgement call with a prop in the way.
In a terrace almost every structural alteration touches a party wall, and there are two of them. Cutting a beam pocket, taking a chimney breast off the shared stack or underpinning near the boundary is notifiable under the Party Wall etc. Act 1996, and the notice is served by you, not by us. We are not party wall surveyors and never act as one. What we supply is the engineer's information your surveyor asks for, and a method and sequence we then actually work to on site.
GS Renovation is a structural contractor first, which is why New Barnet owners call us for the awkward jobs rather than the pretty ones. We appoint the engineer, build strictly to the calculations, work to the party wall method agreed with two sets of neighbours and hold Barnet building control to their inspection stages. Founder led, fully insured, with 30+ years of hands-on experience behind the survey.
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…
What can I say!!! George is an extremely lovely man his workmanship is second to none, he has an excellent eye for detail and nothing was to much…
George was brilliant. Lovely bloke, very reasonably priced and a perfectionist to boot. He completed our small kitchen renovation with care and great…
FAQ
Location itself is not a line on our quotation. Two North London homes of the same age and construction get similar structural alterations figures, and what separates them is condition and access at the EN4 address. GS Renovation does not charge New Barnet homeowners a premium for the address, and there is no travel surcharge within Barnet. The survey establishes the rest. Ring 07472 424 226 with the EN4 postcode and we will confirm before quoting. As a rough guide, structural alterations in London ranges from roughly £1,500 for a simple opening to £15,000 or more where underpinning or major works are involved (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.
Longer than the build alone, because approvals come first. A structural alterations project at an EN4 address needs the engineer's design where the structure requires it, then a Barnet Council application, before the New Barnet programme begins. GS Renovation runs those in parallel wherever possible. The survey costs nothing and is the quickest way to get real dates in Barnet. Ring 07472 424 226 and we will explain which Barnet Council route suits your EN4 property best.
That is the engineer's work, not ours. We are a contractor: for a structural alterations job at a New Barnet address GS Renovation arranges the engineer, the temporary works and the Barnet Council approval, then constructs exactly to the issued design. You receive the calculations for the EN4 property as part of the record. It is the document a buyer's solicitor will want. Ask on 07472 424 226 about Barnet projects. That separation is what protects a Barnet homeowner legally.
Yes, building regulations approval and an engineer's design, and it is notifiable under the Party Wall Act where it falls within three metres of a neighbouring structure. Underpinning at an EN4 address is carried out in controlled bays to keep the existing building stable throughout.
It changes the making good more than the structural element. Bay-fronted Victorian and Edwardian terraces with rear closet wings and side returns rarely have square openings or regular floors, so structural alterations at an EN4 property takes longer in plaster and joinery than in a modern house. GS Renovation shows that as a separate line on the New Barnet quotation. The survey that establishes it is free. GS Renovation will explain on 07472 424 226 how structural alterations are actually priced at an EN4 address in New Barnet itself.
Possibly, and it is worth looking. Victorian and Edwardian bays in EN4 were often built with a timber lintel behind the render or a shallow brick arch, and both fail slowly: a stepped crack from the corner of the opening, a sticking sash, or the bay leaning very slightly forward. Get a structural engineer to look before you fill anything, because filler over a live crack simply hides the movement. If the lintel has gone we prop the opening and fit a new one to their specification, with Barnet building control notified.
We do, and the boundary is not a hard line. What decides it for a structural alterations project is whether GS Renovation can survey the EN4 property, run the New Barnet programme and come back for aftercare without the travel undermining any of it. Most of Barnet and North London qualifies comfortably. Call 07472 424 226 and we will be straight with you. Quotes remain free either way. Aftercare visits to EN4 are part of the same commitment.
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 New Barnet. Explore what else we do locally:
Same Service, Nearby Areas
We carry out structural alterations across New Barnet and the surrounding areas. Explore a nearby location:
Free, no-obligation quote for structural alterations in New Barnet. Rated 4.9 from 31 reviews on MyBuilder, fully insured, and building control handled for you.