Glass box extensions in Whitehaven
Thinking about a glass extension for your Whitehaven home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in WhitehavenFrom £28,500 inc VAT
- PlanningSame limits as single-storey rear; glazing checked for building regs
- Build time10–16 weeks on site
- Postcode districtsCA28

Planning rules that apply in Whitehaven
In England a glazed or orangery-style extension follows the same size limits as any single-storey rear extension: 3 m or 4 m without an application, or up to 6 m and 8 m through prior approval. Building regulations limit glazing to about a quarter of the new floor area plus the openings it replaces, unless whole-house calculations show the design still performs.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
Extensions in and around Whitehaven
Postcode districts we cover around Whitehaven include CA28. We also work in nearby Workington (7 miles), Ulverston (31 miles), Penrith (33 miles), Barrow-in-Furness (34 miles).
Just over the Lancashire border, Morecambe is about 44 miles away. The North West has a high share of Victorian and Edwardian terraces with rear yards and outriggers, plus large areas of inter-war semis in the suburbs.
Glass extension prices in Whitehaven
Prices below are for Whitehaven, using the North West England factor of ×0.95. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Whitehaven: £2,850 to £5,510 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2 m × 4 m 8 m² | £28,500 – £34,500 | £28,500 – £36,000 | £32,500 – £44,500 |
| 3 m × 4 m 12 m² | £34,000 – £41,500 | £39,500 – £50,500 | £49,000 – £66,500 |
| 3 m × 6 m 18 m² | £51,000 – £62,000 | £59,500 – £75,500 | £73,500 – £99,500 |
For a figure based on your own dimensions, use our guide-price tool.
What we take care of
- Design with specialist glazing input
- Drainage details for frameless roofs
- Whole-house energy calculations where needed
- Solar-control and low-energy glass specification
- Steel or glass beams and slim-frame glazing
- Planning drawings that show the glass detail
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Glass extension questions answered
How long does a glass extension take to build in Whitehaven?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
Do you cover all of Whitehaven?
Yes. We cover Whitehaven and the surrounding parts of Cumbria. Site visits are free and there is no obligation.
Who do I contract with for a glass extension in Whitehaven?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
How much does a glass extension cost?
Our guide range is about £2,850 to £5,510 per m² including VAT, because structural glass is made to order. A 12 m² standard-spec glass extension is typically £39,500 to £50,500 in Whitehaven.
Are glass extensions cold in winter?
Modern double or triple glazing with warm-edge spacers and underfloor heating keeps them comfortable. They are not as warm as a solid room, and we explain the trade-off honestly.
Book a free site visit in Whitehaven
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.