Structural Alterations Hendon

GS Renovation carries out structural alterations throughout Hendon, working in the flats that make up most of NW4's homes and the 1930s semis on the streets running towards Finchley and Golders Green. Across our founder's 30+ years on the tools, we have formed new openings, replaced tired joists, underpinned settling foundations and installed supported openings that keep these homes sound.

In Hendon, a simple new opening starts from £1,500, and underpinning a single elevation typically costs £6,000 to £21,000 (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 designs the work, and it 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 and any trial holes first, then the opening, joists or underpinning in the engineer's sequence.
4. Building control inspects each stage before it is covered, then issues the completion certificate.

Structural work on Hendon's suburban houses

The interwar houses on Hendon's residential roads lend themselves to widened openings between kitchen and dining room, new door openings into side extensions, and replacement joists where original timbers have sagged or been weakened over ninety years. Every alteration begins with a structural engineer's assessment, because the internal walls in these 1930s homes frequently carry real load rather than being simple partitions.

For a new opening, the engineer we appoint designs the steel beam or lintel bearing onto padstones; we prop the structure temporarily and cut through in safe stages so the load is never left unsupported. Where old floor joists have failed we splice or replace them to the correct span and grade. Underpinning follows the same discipline, excavating in short sequenced bays to strengthen foundations without undermining the wall above.

Housing in Hendon

Hendon's housing, as the Council Tax list records it, is about 16,060 homes: 38% houses, 62% flats, with 20% pre-1919, 37% interwar and 43% built since 1945. Structural repair to a block in Hendon usually falls to the freeholder, which matters here because most homes are flats.

Structural work in Hendon Church End and its listed buildings

Hendon Church End Conservation Area was designated by Barnet Council on 27 July 1983. There are four listed buildings within it, listed either grade II or grade II*, and it has two locally listed buildings, the Chequers Public House and Church House. For a statutory listed building the listing covers the interior as well as the outside. Structural alterations such as a new opening, a replaced floor or a strengthened roof will almost always need listed building consent, as well as building control approval. Carrying out work to a listed building without that consent is a criminal offence.

Local listing works differently. It does not bring a requirement for listed building consent, but where a planning application is needed the building's local interest is weighed in the decision. For a Hendon owner the practical step is the same in both cases: confirm the status of the building before the structural engineer we appoint starts designing, because the approach changes. Repair of a listed building generally favours keeping and strengthening original timbers and walls over replacing them, and the method statement is likely to be read by the conservation officer as well as by building control.

Regulations and party walls in NW4

Structural alterations inside a Hendon house are controlled under the Building Regulations rather than requiring planning permission, so Barnet Council's building control is the body that inspects and certifies the work. Planning permission comes in only where the outside changes beyond permitted development, which is tighter in a conservation area, or where the home is a flat, since flats have no householder permitted development. A listed building also needs listed building consent for internal structural work.

Many of these interwar semis share a party wall with the house next door, so forming an opening near that wall, underpinning alongside it or bearing a new beam into it makes the work notifiable under the Party Wall Act. You serve the notice on your neighbour as building owner, or your surveyor does; we coordinate the engineer's drawings and calculations, build to any award and line up building control inspections so the alteration is signed off cleanly from start to finish.

Forming a new opening in an outside wall

Widening the back of a Hendon house for glazed doors is a different job from an internal opening, because an external wall is doing more than carrying load. It also keeps water out, so the lintel over the new opening has to be the right type for the wall construction, and in the cavity walls of these interwar houses a cavity tray with stop ends and weep holes goes above it to take any water that gets in back out.

The other consideration is the corner. Removing a long stretch of a rear wall can leave a slender return of masonry carrying the beam at one end, and the engineer may call for a column or a wider pier rather than accepting it. Insulation continuity around the new reveals matters as well, since a cold bridge at the jambs is where condensation and black mould appear a year later. All of it is inspected by Barnet building control.

• Structural engineer appointed and coordinated for the design
• Lintel replacement and repair over failed openings
• Chimney breast removal and support to the stack above

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.

When comparing structural alterations in Hendon with other work, it helps to read home renovation in Hendon, structural alterations across Barnet, a main building contractor in London, when a wall needs underpinning, how we handle structural alterations across London and Lintel Replacement Cost.

Why Hendon Homeowners Choose GS Renovation

Homeowners across Hendon trust GS Renovation for structural alterations because one team owns the entire job. We commission the engineer, manage Barnet Council building control, give you the drawings for any party wall notice on the adjoining semi, and carry out the propping, beams and underpinning ourselves, tidily and safely. Our founder's 30+ years of experience means the signed-off result is right 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.