Home extensions in Henley-on-Thames

What works best for Henley-on-Thames houses?

In the South East, plenty of houses have already been extended once, which makes checking the remaining permitted development allowance an important early step.

Start by comparing orangery extensions, single-storey rear extensions and double-storey extensions: between them they cover most of the layouts we see requested for houses like these.

Where we work near Henley-on-Thames

We cover Henley-on-Thames and the postcode districts RG9. Neighbouring towns we cover include Thame (14 miles), Didcot (14 miles), Abingdon (18 miles), Oxford (20 miles), Wantage (22 miles). Reading, in Berkshire, is roughly 6 miles from Henley-on-Thames and also on our list.

• Thame
• Didcot
• Abingdon
• Oxford
• Wantage

Planning rules in Henley-on-Thames

In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.

In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.

In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.

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).

Popular extension prices in Henley-on-Thames

Prices on this page use our South East England factor of ×1.12, include VAT at 20% and cover the build; your written price follows a survey and agreed drawings.