House Extensions & Loft Conversions in Stoke Newington

LCCL Construction is a design and build company based in Finchley N3, working in Stoke Newington for over 20 years. One team, one contract: architects, structural engineers, project managers and builders coordinated by LCCL take your project from first sketch to handover.

Stoke Newington's Victorian terraces off Church Street and around Clissold Park are side-return and rear-extension houses with roofs that take rear dormers and L-shaped dormers. Narrow plots make rooflights and glazed rear elevations important.

What it costs in Stoke Newington

The final figure depends on postcode, access and site conditions — the instant estimate applies your area. Guide ranges for 2026, design and build inclusive (architecture, structural engineering, planning or LDC, construction, project management and building control). Every project is surveyed and priced individually.

• Velux loft: £32,400 – £50,400 inc. VAT (£27,000 – £42,000 + VAT)
• Rear dormer loft: £56,400 – £80,400 inc. VAT (£47,000 – £67,000 + VAT)
• L-shaped dormer: £58,800 – £98,400 inc. VAT (£49,000 – £82,000 + VAT)
• Hip to gable: £60,000 – £114,000 inc. VAT (£50,000 – £95,000 + VAT)
• Mansard: £76,800 – £148,800 inc. VAT (£64,000 – £124,000 + VAT)
• Rear extension: £42,000 – £90,000 inc. VAT (£35,000 – £75,000 + VAT)
• Side return: £42,000 – £93,600 inc. VAT (£35,000 – £78,000 + VAT)
• Wraparound: £72,000 – £153,600 inc. VAT (£60,000 – £128,000 + VAT)
• Double storey: £90,000 – £198,000 inc. VAT (£75,000 – £165,000 + VAT)

Kitchen on top of the structure, supplied and fitted: +£9,000 – £87,360 inc. VAT (£7,500 – £72,800 + VAT) depending on size and specification. Basements: cellar refit £54,000 – £114,000 inc. VAT (£45,000 – £95,000 + VAT), lowering £114,000 – £216,000 inc. VAT (£95,000 – £180,000 + VAT), new dig £216,000 – £360,000 inc. VAT (£180,000 – £300,000 + VAT)+. New build: £2,200 – £4,500 per sqm (zero-rated for VAT).

A recent LCCL project near Stoke Newington

Weech Road, Hampstead NW6 — penthouse duplex loft conversion

A top-floor flat turned into a penthouse duplex: the kitchen and living space moved up into the new loft, two new bathrooms, an extra bedroom and views across to the Shard, the London Eye and Parliament. LABC Building Excellence Awards 2026 London Regional Winner — Best Conversion or Alteration to an Existing Home.

See the project

Planning in Stoke Newington

Hackney; the Stoke Newington and Clissold Park conservation areas need planning permission for roof extensions; rear extensions outside them usually pass under permitted development with prior approval for the larger ones.

Conservation areas and Article 4 directions in Stoke Newington

The Stoke Newington conservation area (designated 1983, revised 2004) covers the historic centre, and Clissold Park (1969) takes in the park and the listed houses on its edges; Clapton Square and Clapton Common (both 1969) lie to the east. None of these four has an Article 4 direction — Hackney’s householder Article 4 directions are limited to Shacklewell Green (from 22 October 2019), Brownswood and Well Street (from 9 May 2025) and Beck Road (28 May 2025) — so replacement windows and other front-facing works remain permitted development. What changes inside the conservation areas is the roof: Hackney’s new Residential Extensions and Alterations SPD says roof extensions on an unaltered roofline “will not generally be acceptable” and hip-to-gable conversions are not acceptable. On the N16 streets outside the boundaries — much of the Victorian and Edwardian terraces towards Stamford Hill and Dalston — lofts and single-storey rear extensions usually go through on a Lawful Development Certificate, with the larger 6 m rear extension available through prior approval.

Extension size rules Hackney applies (SPD in effect January 2026)

Hackney approved its Residential Extensions and Alterations SPD in December 2025 and it has applied since January 2026, replacing the 2009 guidance under Local Plan LP33. Single-storey rear extensions are accepted up to 3 m on a terrace, 3.5 m on a semi and 4 m on a detached house (section 3.5), keeping at least half the original rear garden and staying below first-floor sills. Two-storey rear extensions are limited to half the width and half the ground-floor depth of the house, one storey below the eaves. Side extensions are no more than half the width, 1 m from the boundary and 500 mm behind the front building line. Rear dormers sit at least 0.5 m below the ridge and in from the hips, 1 m above the eaves and no more than half the roof height; mansards outside conservation areas have a lower slope of no more than 70 degrees. Basements (section 7) are single storey with a footprint under 1.5 times the house, extending no more than half the house depth into the garden and no more than half the garden depth, with lightwells over no more than half the front garden and 2.15 m headroom.

Light to neighbours

Hackney codifies the 45-degree test: an extension should not cross a 45-degree line from the centre of the nearest neighbouring ground-floor habitable-room window, on plan and on elevation, with BRE calculations where the impact may be significant. We design to the line from the outset.

Fees and timescales

A householder application costs £548 (from April 2026, plus the Planning Portal charge) with an eight-week target. Hackney’s pre-application advice from 1 April 2026 is £310 for a written householder response (£155 for a follow-up) and £430 for a listed building. Party wall notices run alongside planning: two months’ notice for works to a shared wall, one month for excavations within 3 m or 6 m of a neighbour’s foundations.

Building control

Hackney runs its own building control service and is an LABC member. We use the council inspector on every project. Typical inspection points are commencement, foundation trenches, oversite and damp-proof course, drainage before backfill, structural steels and joists before they are covered, insulation and fire-stopping before plastering, then completion. We book each one and hand you the completion certificate at the end of the job.

Anderson's advice: budget for the steelwork, not just the kitchen

Clients budget for kitchen units but forget the structural steelwork when opening up ground-floor walls. On a Victorian terrace that is typically £4,800 – £19,200 inc. VAT (£4,000 – £16,000 + VAT) for the load-bearing opening, depending on its width — we price it on every proposal so there is no surprise.

What our clients say

“Super professional and on the ball at all times. All his teams are excellent and hard working. They are conscientious and want the job to be well done.”

— Ludovic, Reviews.io

As LABC Building Excellence Award winners in 2024 (Best Residential Extension in London) and 2026 (Best Conversion or Alteration to an Existing Home, Weech Road NW6), every project is delivered by one team of architects, structural engineers, project managers and builders. Workmanship is guaranteed for 12 months from practical completion, with a 10-year LABC structural warranty.

Nearby areas

Stoke Newington is part of our North London guide. Nearby areas: Barnet, Finchley, Enfield, Edgware, Hendon, Muswell Hill, Highgate, Crouch End.

To book a free consultation call LCCL Construction on 020 8037 7332 or get an instant estimate online. Get an instant estimate or book a free consultation.

One team, one contract, one point of contact — from first sketch to handover.