Cumbria
Rear extensions in Whitehaven
We design and build rear extensions for homes in Whitehaven, Cumbria, from single-storey kitchen-diners across the back of the house to two-storey extensions that add a bedroom above.
Whitehaven is in Cumbria, with postcode districts including CA28. The nearest places we also cover are Workington (6.7 miles) and Ulverston (31.3 miles).
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
Rear extensions we build in Whitehaven
- Single-storey rear extensions
- Two-storey rear extensions
- Kitchen-diner rear extensions
- Side return extensions
- Wraparound extensions
- Glazed and glass-box rear extensions
- Rear extensions for terraced houses
- Rear extensions for semi-detached houses
- Rear extensions for bungalows
- Rear extension plans and planning applications
Also available across Cumbria:
- Rear extensions for detached houses
- Flat-roof rear extensions
- Pitched and lean-to roof rear extensions
- Knocking through to a rear extension
- Roof lanterns and rooflights for rear extensions
- Permitted development rear extensions
- Larger home extension prior approval (England)
- Building Regulations for rear extensions
Rear extension prices in Whitehaven
North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Example | Guide inc VAT |
|---|---|
| Single-storey, 3 m × 4 m (12 m²) | £21,500–£35,000 |
| Single-storey, 4 m × 6 m (24 m²) | £43,000–£70,000 |
| Two-storey, 3 m × 5 m footprint (30 m²) | £51,000–£76,000 |
| Side return, about 14 m² | £30,500–£50,000 |
| Wraparound, about 25 m² | £51,500–£84,500 |
What are homes in Whitehaven like to extend?
Stone and brick terraces are common around Whitehaven. Where houses back onto a ginnel or alley, deliveries can come in from the rear, which makes the build tidier.
Planning rules for Whitehaven
English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres within 2 metres of a boundary.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
Every rear extension in England needs Building Regulations approval, whether or not planning is needed. You can use the council's building control service or a registered building control approver, by full plans (checked before work, usually within five weeks) or a building notice, and you get a completion certificate at the end.
Nearby towns
FAQ
Questions people ask
How much is a rear extension in Whitehaven?
A 3 m × 4 m single-storey rear extension is about £21,500–£35,000 including VAT at our North West England guide rates; the written price follows a survey.
Do I need planning permission in Whitehaven?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
Is the site visit in Whitehaven free?
Yes, with no obligation.
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.