Covering Swanley
Swanley sits 17 miles north-west of Maidstone, with Bexley 3 miles to the north and Dartford 4 miles to the north-east.
Homes in the South East
Housing across the South East mixes inter-war semis, post-war estates and older cottages in villages and market towns, so rear and side extensions, hip-to-gable lofts and garage conversions all come up regularly.
What is a single-storey extension?
We design the extension around how you use the house: where the light comes from, how the new room joins the old one, and what happens to the drains and the garden. The structure is built in brick or block to match the house, finished with a flat roof and lantern or a pitched roof, then insulated, plastered and handed back ready to decorate.
- Measured survey and design drawings
- Foundations, drainage and structural steel
- Brickwork, roof, glazing and insulation
What will a single-storey extension cost?
Typical ranges for single-storey extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| Single-storey extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £2,600 to £3,000 per m² |
| Good specification | £3,000 to £3,500 per m² |
| High specification | £3,500 to £4,000 per m² |
How is a single-storey extension approved in Swanley?
In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.
In England a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary.
What should I think about before starting?
- Drains under the footprint may need diverting or a build-over agreement with the water company.
- Large glazed areas need to meet energy rules, which can shape the size of doors and rooflights.
What happens after I enquire?
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
Your questions answered
Can we stay in the house during the build?
Usually yes. We keep the existing house closed off from the works until the knock-through near the end, and agree a temporary kitchen set-up with you if the kitchen is affected.
Will the brick match?
We source the closest available match for colour, size and texture and agree a sample panel with you before laying.
Who deals with the council for a project in Swanley?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Other towns nearby
- Single-storey extensions in Bexley
- Single-storey extensions in Dartford
- Single-storey extensions in Welling
- Single-storey extensions in Eltham
Learn more about single-storey extensions, or see every project we cover in Swanley.

