Bungalow and upward extensions in Streatham

Covering Streatham

Alongside Streatham, we also cover Mitcham, Brixton (3 miles to the north-east) and Wimbledon.

Homes in London

Terraced houses dominate many London neighbourhoods, so most projects involve shared walls, narrow access and a party wall process. Conservation areas are widespread, and some boroughs have their own mansard and basement guidance.

What is an upward extension?

An upward extension adds a new storey on top of an existing house, most often turning a bungalow into a two-storey or chalet-style home. It can double the floor area without using any of the garden.

Design and planning or prior approval application
Staircase and changes to the ground floor layout
Full fit-out of the new rooms

How much should I budget for an upward extension?

What bungalow and upward extensions typically cost. These are guide ranges; the written quote for your house replaces them.

Bungalow and upward extensions	Guide price incl. VAT
Chalet conversion with dormers (total)	£45,000 to £85,000
New first floor, standard specification	£2,200 to £2,800 per m²
New first floor, good specification	£2,800 to £3,300 per m²
New first floor, high specification	£3,300 to £3,800 per m²

Do you need permission for an upward extension in Streatham?

Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.

In England, Class AA permitted development allows an extra storey on many detached and semi-detached houses built between July 1948 and October 2018, subject to a prior approval application covering design, neighbours’ amenity and other matters. Houses in conservation areas and other protected land need full planning permission, as do most chalet conversions with front dormers.

What can change the price or programme?

The staircase takes space from the ground floor plan.
Neighbours’ light and privacy are the main planning tests.

What are the steps?

Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.

Questions about an upward extension in Streatham

Do we need to move out?

Often for part of the job, while the roof is off and the new floor is formed. We plan this with you.

How long does it take?

About 12 to 24 weeks on site.

Who deals with the council for a project in Streatham?

We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.

Also covering

Learn more about bungalow and upward extensions, or see every project we cover in Streatham.