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 Rawmarsh?
In Rawmarsh, a side extension typically costs £1,600–£2,450 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £45,000–£68,500. Building costs in Yorkshire and the Humber run about 7% below the UK average, and the figures for Rawmarsh are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £32,000–£49,000 |
| Typical project (28 m²) | £45,000–£68,500 |
| Larger project (39 m²) | £62,500–£95,500 |
| Rate per m² | £1,600–£2,450 |
What moves the price most:
- Boundary walls and access for materials
- Single or two storeys
- Steel work where the side wall is opened
- Drains, gas meters or soil pipes that need moving
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a side extension in Rawmarsh?
Whether you need planning permission depends on your house and its location in 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.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
What we take care of:
- Foundations and drainage alterations
- Building control completion
- Survey of the boundary, drains and access
- Electrics, heating and plastering
- Planning drawings and application
- Structural calculations
How long does it take?
Expect 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 Rawmarsh
In Yorkshire, through-terraces and back-to-backs have particular constraints, while semis and detached houses suit larger extensions.
If your home is in Rawmarsh or close by in Rotherham, Chapeltown and Sheffield, a free home visit is the first step.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about side extensions in Rawmarsh
How much does a side extension cost in Rawmarsh?
In Rawmarsh, a side extension typically costs £1,600–£2,450 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £45,000–£68,500. Your fixed price depends on the survey and drawings.
Who approves a side extension in Rawmarsh?
Planning matters in Rawmarsh go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
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.
How long does it take?
Roughly 10 to 16 weeks on site once approvals are in place, depending on whether it is one or two storeys.
Will I lose my driveway?
A side extension often takes the side drive. We look at whether parking can be kept at the front and whether a dropped kerb is needed.