Isle of Wight
Rear extensions in Cowes
Rear extensions in Cowes: single-storey and two-storey extensions, side returns, wraparounds and glass-led designs, planned around Victorian terraces and Edwardian villas and the English rules.
Cowes is in the Isle of Wight, with postcode districts including PO31. The nearest places we also cover are East Cowes (0.5 miles) and Newport (4.2 miles).
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.
Rear extensions we build in Cowes
- 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 the Isle of Wight:
- 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 Cowes
South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Example | Guide inc VAT |
|---|---|
| Single-storey, 3 m × 4 m (12 m²) | £25,500–£41,500 |
| Single-storey, 4 m × 6 m (24 m²) | £51,000–£83,500 |
| Two-storey, 3 m × 5 m footprint (30 m²) | £60,500–£90,500 |
| Side return, about 14 m² | £36,000–£59,500 |
| Wraparound, about 25 m² | £61,500–£101,000 |
What are homes in Cowes like to extend?
Cowes has a mix of Victorian terraces near the centre and larger Edwardian and inter-war houses further out. Clay soils across much of the South East mean deeper foundations near trees, which we plan for at the survey.
Planning rules for Cowes
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is within 2 metres of a boundary.
England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.
Planning and Building Regulations are separate in England: even a permitted development extension is inspected for foundations, drainage, structure, insulation, fire safety and ventilation, through the council or a registered building control approver, ending with a completion certificate.
Nearby towns
FAQ
Questions people ask
How much is a rear extension in Cowes?
A 3 m × 4 m single-storey rear extension is about £25,500–£41,500 including VAT at our South East England guide rates; the written price follows a survey.
Do I need planning permission 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.
Is the site visit in Cowes free?
Visits here are by arrangement; we confirm first and agree any travel costs.
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.