House extension in East Finchley

Connect the added space to the existing home.

Start with the house extension brief

Begin with how the new space will meet the old rooms, garden and circulation. A measured brief should record boundaries, levels, existing drains, neighbouring windows and the parts of the building you intend to keep.

Develop daylight, structure and services alongside the floor plan. Agree which openings and finishes are included, how the existing home will be protected during construction and which decisions need surveys or approval before a quotation.

The local building context

Barnet’s 2010 introduction to the Hampstead Garden Suburb appraisal says the Suburb was developed between 1907 and 1938, and that by 1914 work had begun on extending it into the 300 acres linking it to East Finchley Underground Station. Building there came later: the Ossulton Way and Hill Top appraisal dates its earliest buildings to 1927, and Holne Chase and Norrice Lea were built between 1935 and 1938, the Suburb’s final major building phase. Brim Hill’s mainly semi-detached houses date from 1931 to 1938.

Flats are part of the Suburb’s mix. The Market Place and Lyttelton Road appraisal records a first block of shops with flats above, built in 1922, and three developments of blocks of flats along Lyttelton Road between 1929 and 1936, continuing the Suburb’s tradition of mixed housing. Belvedere Court, designed by Ernst Freud in 1937, is a Grade II listed Modernist block of flats, and the Ossulton Way appraisal records flats and maisonettes alongside large semi-detached and detached houses with garages and gardens.

East Finchley names a neighbourhood, not a consent route. Barnet lists Cherry Tree Wood as an East Finchley N2 open space, while Haringey planning committee reports cover N2 sites on Fortis Green and Southern Road, and the Suburb’s conservation area and the Trust’s Scheme of Management do not share one boundary. Check, in turn, which council covers the address, the conservation-area map and any list entry, whether an Article 4 direction or the Trust’s Scheme applies, and then the lease or title with the planning history. The Trust cannot answer queries without the address.

Local design and consent context

Barnet designated the Hampstead Garden Suburb Conservation Area in December 1968, and its older part was recognised as being of outstanding architectural or historic interest in 1977. East End Road forms its northern boundary at Ossulton Way, and The Bishop’s Avenue its eastern boundary. The Trust says the appraisal, formally adopted in October 2010, is divided into 22 character areas; The Bishop’s Avenue has its own appraisal, approved on 1 February 1999.

Haringey designated the Fortis Green Conservation Area on 1 March 1974 and lists no current adopted appraisal for it. A 2022 committee report placed a site on Fortis Green inside the conservation area, while a 2016 report placed the reservoir site on Southern Road outside both the Fortis Green and Muswell Hill conservation areas. None of Barnet’s 16 conservation areas is named East Finchley, so check each address against the council’s records rather than the neighbourhood name.

Barnet introduced an Article 4 Direction for most of the Hampstead Garden Suburb Conservation Area shortly after designation, in 1971. Its 2010 management proposals list the restrictions then in force, among them replacement of windows, doors and roofing materials, porches, outbuildings, vehicular hardstandings, new gates, fences or walls and painting of external walls, and propose updating the direction. The national planning data record for the direction, starting on 5 March 1971, lists the permitted development classes it withdraws in today’s numbering; check the current position with Barnet.

Access and site planning

Start from the route between the kerb and the room: where materials arrive, where waste is held and how shared entrances are protected. On a Haringey road, scaffolding or hoarding on the road or footway needs a licence lasting 3 months; a skip needs a licence applied for at least 5 working days ahead, for up to 28 days; and a skip in a parking bay needs a bay suspension requested at least 2 weeks before. On a Barnet road, check Barnet’s licence and suspension arrangements. Lyttelton Road was designated the A1 in 1983, and the GLA Roads Designation Order 2000 made the A1 from the edge of London to Wakley Street a GLA road; TfL licenses activities only on its red routes, so check the frontage.

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The East Finchley area guide · House extension across London · Hampstead Architecture & Planning · Hampstead Chartered Surveyors

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