Wraparound Extension in East Finchley N2

Why East Finchley Properties Choose Us

Leafy, 1930s houses, near Highgate Wood. Mix of Art Deco and Victorian properties. Our team works exclusively in NW London, bringing detailed knowledge of Barnet planning requirements and the specific challenges of 1930s houses stock.

Planning Authority

Barnet LBC

Average Property Value

£900,000

Conservation Area

No

Typical Project Cost

£90,000–£200,000

How a Wraparound Extension Works — Step by Step

1. 1

   Ground Floor Survey and Feasibility

   We assess the full rear and side return footprint available, mapping drainage, utilities, trees, and party wall positions. A wraparound extension is a major ground floor reconfiguration — we model the new open-plan layout and stair positions to confirm the scheme is feasible before committing to design fees.

2. 2

   Planning Application Strategy

   Wraparound extensions always require full planning permission in conservation areas and Article 4 zones — they are significant developments. We develop a planning strategy including pre-application advice, heritage impact assessment, and Design and Access Statement. In Hampstead Garden Suburb, HGS Trust consent is required alongside Barnet LBC planning.

3. 3

   Architectural Design

   The architect designs the L-shaped extension footprint, roof strategy (combinations of flat roof, lantern lights, and pitched sections), and the treatment of the rear elevation. Rooflight runs along the inner angles of the L bring daylight into the heart of the new plan. Material selection for the external envelope is driven by planning requirements.

4. 4

   Structural Engineering

   A structural engineer designs the new foundations (typically a reinforced concrete slab or strip footings), the structural steel frame for any large clear spans, and the lintels and beams for the wall openings into the existing house. Party wall and building regs calculations are prepared simultaneously.

5. 5

   Demolition, Utilities, and Groundworks

   Existing outbuildings in the rear and side are demolished. Drainage is diverted around the new footprint. Foundations are poured and inspected by building control. Any underfloor heating systems are laid into the ground floor slab at this stage — it is not possible to retrofit UFH into a solid concrete slab after the fact.

6. 6

   Superstructure Construction

   The L-shaped shell is constructed in masonry, timber frame, or structural insulated panels. The roof structure — typically a combination of flat warm roof and large pivot rooflights — is built and made weathertight. External works including drainage and landscaping connections are completed at this stage.

7. 7

   Main House Integration — Opening the Rear Wall

   With the extension weathertight, the rear wall of the existing house is opened up in one operation, inserting the structural steel frame or lintel that carries the floor above. The temporary propping is removed once the steel has cured into the masonry. The transformation of the ground floor is immediately apparent.

8. 8

   Fit-Out and Completion

   First and second fix services, kitchen, underfloor heating commissioning, plastering, tiling, and decoration are completed. Building control inspects at every key stage and issues a completion certificate. The finished product — a fully open-plan kitchen, dining, and living space spanning the full width and depth of the ground floor — is the most popular home improvement in NW London.

Wraparound Extension in East Finchley — Planning and Local Considerations

East Finchley in Barnet LBC is the most permissive planning environment for wraparound extensions in the matrix. While the wraparound footprint always requires full planning permission (combining rear and side extensions exceeds PD limits in most cases), Barnet planners are receptive to well-designed proposals on N2 properties. The 1930s semi-detached stock has good garden depths and side passages, and build costs in N2 are typically 20–30% lower than NW3 for equivalent specification.

Frequently Asked Questions