A double-storey extension adds two floors of new space to your house in one build, typically a larger kitchen or living room downstairs with an extra bedroom, bathroom or en-suite above, sharing one set of foundations and one roof.
If you live in Reigate and are weighing up a double-storey extension, the starting point is a visit to measure up and talk through what you want, which costs nothing. We cover homes across RH1 and RH2, and a typical project of this kind in the South East lands somewhere in the £67,000–£134,000 bracket, including VAT. The exact figure depends on size, access and the finish you choose.
- Guide price
- £67,000–£134,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- RH1 and RH2
- Planning rules
- England
- Local area
- Surrey
- Survey
- Free, with a written quote
How much does a double-storey extension cost in Reigate?
No two jobs cost exactly the same, but the ranges below give a fair picture of a double-storey extension in Reigate. Pricing for the South East runs about 12% above the national guide, and the overall guide is £67,000–£134,000 with VAT included. We'll confirm your figure after surveying the property for free.
| Type of job | What it usually involves | Guide in Reigate |
|---|---|---|
| Small (15–20m² total) | A compact rear or side extension adding a small room on each floor. | £45,000–£73,000 |
| Typical (30–40m² total) | A larger kitchen or living room below with a double bedroom or en-suite above. | £67,000–£134,000 |
| Large (50m² plus total) | Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing. | £112,000–£202,000 |
The main things that change the figure:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Foundation depth, ground conditions and drains to divert
- Scaffolding duration, access and the level of finishes
What do you get?
- Groundworks, foundations and below-ground drainage
- Insulated cavity walls with brick or render to match the house
- First-floor joists, stud walls and new openings upstairs
- Roof structure tied into the existing roof, tiled to match
- Windows, external doors, plastering and internal doors
- Building control inspections and completion certificate
Homes in Surrey
Surrey has many Victorian and Edwardian villas, interwar semis in the commuter towns near London, and Arts and Crafts houses with tile-hanging and tall chimneys. Bargate stone appears around Godalming, and large detached homes are common in Guildford, Woking, Weybridge and the Surrey Hills villages.
Larger homes often take kitchen extensions, bifold doors, landscaping and driveway renewal. Interwar semis suit loft and side extensions, while tile-hung and period properties may need roof and hanging-tile repairs.
If your house in Reigate fits one of these patterns, it helps us anticipate what a double-storey extension will involve, though we always confirm the details on site.
Permissions for a double-storey extension in Reigate
Reigate is in England, so the planning and building rules set out below are the ones that apply. We confirm the details with the council before we quote.
In England, a two-storey rear extension can only be permitted development if it is no more than 3 m deep, at least 7 m from the rear boundary and finished to match the house. Most double-storey and all two-storey side extensions need full planning permission.
Building Regulations approval is needed, with structural calculations for beams, foundations and the roof. The Party Wall etc. Act 1996 often applies on semi-detached and terraced houses.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
From survey to handover
Survey and measure
We begin by looking at the job in person. During the free survey we discuss options, materials and budget for a double-storey extension, and photograph or measure anything the quote needs to reflect.
Your fixed price
The quote arrives in writing, not over the phone. It covers the full scope, the finishes you've chosen, any exclusions and the payment schedule, with a fixed price tied to that specification.
Dates and permissions
We handle the paperwork side: checking whether planning permission or building control approval is needed, submitting applications where they are, and scheduling the trades and materials around your dates.
Finish and handover
On site, the agreed plan is followed and any change is put in writing first. At completion we do a final clean, go through the snagging list with you and leave you with the relevant documents.
What you can expect from us
Double-storey extensions in Reigate: questions
Can you combine a double-storey extension with other work?
Yes. Because we manage several trades under one contract, we can plan a double-storey extension alongside other work on your Reigate home, such as new windows with rendering, or a kitchen refit with an extension. Combining jobs can reduce repeat set-up such as scaffolding, skips and access, and every element is listed and priced in the same written quote.
Can the new upstairs room have its own bathroom?
A new upstairs room can usually have an en-suite, provided waste pipes can reach the soil stack or a new one can be installed. Running the waste pipe to the right falls is the main design question, and a pumped system is an option where gravity will not work. We plan bathroom positions at the design stage so pipes, ventilation and insulation are built in rather than added later.
Can we live at home while it is built?
Most families stay at home during a double-storey extension. The new structure is built outside first, and we only break through into the existing rooms near the end, usually one floor at a time. Upstairs, this may mean a bedroom is out of use for a week or two. We fit dust screens, protect floors and stairs, and plan any time without water or power in advance.
Do you cover Redhill, Horley and Banstead?
Yes. As well as Reigate, we cover Redhill, Horley and Banstead and the rest of Surrey. Our coverage is UK-wide, so the process is the same wherever you are: a free site survey, a quote in writing that fixes the price for the agreed scope, and one point of contact while the work is planned and carried out.
How is the new roof joined to the existing house?
The new roof is usually tied into the existing roof so the two read as one. On a rear extension this often means a lower ridge or a hipped end, with valleys where the slopes meet. We strip back some existing tiles, fix new rafters and battens, and lay matching tiles or slates. Lead or proprietary flashings seal the junctions so water runs off properly.
Also covering areas around Reigate
If your address falls within RH1 and RH2, we cover it. The same goes for neighbouring Redhill, Horley and Banstead, which we include alongside Reigate when arranging surveys and quotes.

