What is a side extension?
A side extension builds into the space beside a semi-detached or detached house, often over a driveway or side passage. It can be single-storey, for a utility room, downstairs toilet or study, or two-storey to add a bedroom above.
How much does a side extension cost in Godalming?
In Godalming, a side extension typically costs £1,900–£2,950 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £53,000–£82,500. That range is adjusted for the South East, where domestic building work typically costs around 12% above the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £38,000–£59,000 |
| Typical project (28 m²) | £53,000–£82,500 |
| Larger project (39 m²) | £74,000–£115,000 |
| Rate per m² | £1,900–£2,950 |
The main things that change the cost:
- Steel work where the side wall is opened
- Internal fit-out of the new rooms
- Drains, gas meters or soil pipes that need moving
- Single or two storeys
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a side extension in Godalming?
Approvals for a side extension in Godalming follow the rules for England. In England a single-storey side extension can be permitted development if it is no more than 4 metres high and no wider than half the width of the original house. Side extensions of more than one storey always need planning permission, as do side extensions in conservation areas, National Parks and National Landscapes.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
We check this for your address before design work starts, so there are no surprises later.
What we handle
Handled as part of most side extensions:
- Building control completion
- Planning drawings and application
- Electrics, heating and plastering
- Structural calculations
- Survey of the boundary, drains and access
- Opening into the existing house
How long does it take?
Allow 10 to 16 weeks on site depending on size and storeys. Design and approvals come first and typically take 3 to 4 months, depending on the approval route.
Building in Godalming
The South East has a broad mix of housing, from Victorian terraces in the towns to post-war semis and newer estates, so extension types vary street by street.
Our Godalming coverage includes postcode districts GU7, and we also work in nearby places such as Guildford, Aldershot and Farnham.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about side extensions in Godalming
How close to the boundary can I build?
You can build up to the boundary, but the eaves height near it is limited under permitted development, and planning officers often want a gap at first floor. If you build on or near a shared boundary, party wall rules may apply.
How much does a side extension cost in Godalming?
In Godalming, a side extension typically costs £1,900–£2,950 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £53,000–£82,500. Your fixed price depends on the survey and drawings.
How long does a side extension take in Godalming?
Typically 10 to 16 weeks on site depending on size and storeys. Design and approvals beforehand usually take 3 to 4 months.
Will a two-storey side extension look odd?
Not if it is designed well. Setting it back from the front and keeping the roof lower than the main ridge usually gives a natural look and is what most councils ask for.
Can a side extension go over a drain?
Often yes, with a build-over agreement from the water company or by rerouting the drain. We check this during the survey.