Home Extensions in Runnymede Borough
Runnymede Planning Guide
We have completed over 136 home extension and loft conversion projects across Runnymede Borough since 2014 — in Egham, Chertsey, Addlestone and Virginia Water.
Runnymede is one of the more demanding planning authorities we work with. Not unpredictable — but more detailed in what it expects, and more rigorous around certain issues than some neighbouring boroughs. Flood risk is the biggest one, and it has become significantly more complex in recent years.
Areas we cover in Runnymede
Egham (TW20) — 57 projects
Chertsey (KT16) — 35 projects
Addlestone (KT15) — 34 projects
Virginia Water (GU25) — 10 projects
Flood risk in Runnymede — what has changed
Following widespread flooding across parts of the borough, Runnymede Borough Council now has a dedicated flood officer. Applications are scrutinised much more carefully than they were two or three years ago. If your property falls within Flood Zone 2 or 3, a Flood Risk Assessment must be submitted before your application can be validated. No assessment, no registration. It is as simple — and as serious — as that.
Flood risk does not affect every property in Runnymede. It is most relevant on lower-lying roads near the River Thames, around Egham Hythe, and near local watercourses. But it affects more properties than people expect. We check flood zone status at the pre-planning consultation, at no charge, so there are no surprises later. Where a Flood Risk Assessment is needed, we coordinate it with specialist consultants as part of our planning service. It adds time and cost — which is exactly why catching it early matters.
Conservation areas in Runnymede
Runnymede has a significant number of conservation areas. Here are the key ones relevant to the areas we work in:
- Egham — designated in 1993. Egham Hythe — centred on properties adjoining the River Thames.
- Englefield Green — revised conservation area appraisal from December 2023, with updated design expectations now actively applied.
- Chertsey — covering the historic town centre.
- Thorpe — a smaller rural and village character area. Basingstoke Canal and Wey Navigation — linear areas following the waterways.
- Caxton Avenue, Addlestone — a residential conservation area.
Being in a conservation area does not stop you extending. But it does mean design quality, materials, and the way the extension relates to the street are all looked at carefully. We assess your position at the free consultation, before any design begins.
Frequently asked questions
If your property falls within Flood Zone 2 or 3, yes — Runnymede Borough Council will not validate your planning application without
one. This applies most often on lower-lying roads near the Thames, in Egham Hythe, and near local watercourses. We check your flood zone status at the free consultation, before any design work begins.
Egham, Egham Hythe, Englefield Green, Chertsey town centre, Thorpe, the Basingstoke Canal and Wey Navigation corridors, and Caxton Avenue in Addlestone all carry conservation area designation. Each has its own design expectations, which is why we check your specific position rather than apply a generic answer.
It depends on the size, the property, and whether it falls within a conservation area or a flood risk zone. Many single storey rear extensions are achievable under Permitted Development, but anything beyond standard limits, or affected by flood risk, usually needs a full planning application.
Yes. A pre-application enquiry is a good way to test a design before committing to a full submission — as we did for the Chertsey bungalow project referenced on our Chertsey page — and we would recommend it for anything beyond a straightforward rear extension.
Ready to start your Runnymede project?
Call us on 020 3865 4917 or 0800 043 8838. Free consultation, no pressure, honest advice — including an upfront check of your flood zone and conservation area position.
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