Workington, Cumbria
Semi-detached rear extension in Workington
For homes in Workington, a semi-detached rear extension is often the simplest way to gain space without moving. Single or two-storey extensions for semi-detached houses, with side access and one party wall. We take it from survey to completion certificate.
Workington sits in Cumbria, with postcode districts including CA14. Where a Workington semi already has a small lean-to at the back, we usually replace it rather than extend it.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a semi-detached rear extension cost in Workington?
Guide prices for a semi-detached rear extension in Workington start from our North West England rate of £1,790–£2,910 per square metre, including VAT. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,500–£35,000 |
| 4 m wide × 5 m deep (20 m²) | £35,500–£58,500 |
| 4 m wide × 6 m deep (24 m²) | £43,000–£70,000 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a semi-detached rear extension in Workington?
The planning route for a semi-detached rear extension in Workington is set by England's householder rules and your council.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.
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.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Workington like to extend?
Workington has long runs of terraced houses with back yards and alleys, plus 1930s semis further out. Yard extensions on terraces are often single-storey and close to both boundaries.
How a semi-detached rear extension in Workington comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Semi-detached rear extensions near Workington
From Workington, the nearest places we also cover are Whitehaven (6.7 miles) and Annan (26.5 miles).
- Semi-detached rear extension in Whitehaven
- Semi-detached rear extension in Annan
- Semi-detached rear extension in Dumfries
- Semi-detached rear extension in Carlisle
- Semi-detached rear extension in Penrith
Other work in Workington:
FAQ
Semi-detached rear extension questions in Workington
Is the site visit in Workington free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
What postcode areas do you cover around Workington?
Including CA14, and the surrounding Cumbria area.
Do I need a party wall agreement?
Usually with the attached neighbour, in England and Wales.
Do I need planning permission for a rear extension in Workington?
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.
Do you handle building control in Workington?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
How much does a semi-detached rear extension cost in Workington?
As a guide, £1,790–£2,910 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £21,500–£35,000 at that rate. Your written price follows the survey.