Oxfordshire
Rear extensions in Henley-on-Thames
Rear extensions in Henley-on-Thames: single-storey and two-storey extensions, side returns, wraparounds and glass-led designs, planned around commuter semis and detached houses and the English rules.
Henley-on-Thames is in Oxfordshire, with postcode districts including RG9. The nearest places we also cover are Marlow (6.0 miles) and Reading (6.1 miles).
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Rear extensions we build in Henley-on-Thames
- 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 Oxfordshire:
- 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 Henley-on-Thames
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 Henley-on-Thames like to extend?
Commuter semis and detached houses make up much of Henley-on-Thames, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
Planning rules for Henley-on-Thames
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.
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.
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 Henley-on-Thames?
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 Henley-on-Thames?
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 Henley-on-Thames 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.