Cowes, Isle of Wight
Glazed rear extension in Cowes
Thinking about a glazed rear extension in Cowes? Full-height glass, slim frames and big rooflights for the most open rear room. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Cowes sits in the Isle of Wight, with postcode districts including PO31. If your garden in Cowes faces south, expect us to talk about overhangs and solar-control glass before frame colours.
Ask about a site visit
Visits here are by arrangement; we'll confirm before booking.
Cowes is outside our regular coverage, so visits and projects here are by arrangement: we confirm whether we can take the job, and agree any travel costs, before the first visit.
How much does a glazed rear extension cost in Cowes?
For Cowes we work from the South East England rate: £3,140–£5,380 per square metre of new floor, including VAT, standard specification. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £37,500–£64,500 |
| 4 m wide × 6 m deep (24 m²) | £75,500–£129,000 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a glazed rear extension in Cowes?
Whether your glazed rear extension in Cowes needs a planning application depends on its size, your house and any local restrictions.
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.
New fabric must meet Approved Document L (2021 edition incorporating 2023 amendments): walls 0.18, roof 0.15 and floor 0.18 W/m²K, windows 1.4 W/m²K or Band B. Under the simple route, new windows, doors and rooflights should not exceed 25% of the extension floor area plus any openings removed; more glass is possible with a whole-house calculation.
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 Cowes like to extend?
Commuter semis and detached houses make up much of Cowes, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How a glazed rear extension in Cowes comes together
Survey visit
We measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
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.
Glazed rear extensions near Cowes
From Cowes, the nearest places we also cover are East Cowes (0.5 miles) and Newport (4.2 miles).
- Glazed rear extension in East Cowes
- Glazed rear extension in Newport
- Glazed rear extension in Ryde
- Glazed rear extension in Sandown
- Glazed rear extension in Shanklin
Other work in Cowes:
FAQ
Glazed rear extension questions in Cowes
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
How long does a rear extension take to build in Cowes?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Is a glass box a conservatory?
No. It is built to Building Regulations as part of the house, with insulated floor and roof, so it is usable all year.
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.
Do I need planning permission for a rear extension in Cowes?
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.
How much does a glazed rear extension cost in Cowes?
As a guide, £3,140–£5,380 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £37,500–£64,500 at that rate. Your written price follows the survey.