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.
Across Bristol, people look into a double-storey extension to replace something worn out, to make the house work better for them, or to get it ready for a sale. We cover Bishopsworth and the smaller towns around them, working to the rules that apply in England. Expect a guide of £61,000–£122,000, VAT included, in the South West, and every quote follows a free visit.
- Guide price
- £61,000–£122,000 inc VAT
- Time on site
- 14–22 weeks on site
- Planning rules
- England
- Price level
- About 2% above the national guide
- Towns listed
- 1
- Survey
- Free, with a written quote
Double-storey extensions prices in Bristol
No two jobs cost exactly the same, but the ranges below give a fair picture of a double-storey extension in Bristol. Pricing for the South West runs about 2% above the national guide, and the overall guide is £61,000–£122,000 with VAT included. We'll confirm your figure after surveying the property for free.
| Type of job | What it usually involves | Guide in Bristol |
|---|---|---|
| Small (15–20m² total) | A compact rear or side extension adding a small room on each floor. | £41,000–£66,000 |
| Typical (30–40m² total) | A larger kitchen or living room below with a double bedroom or en-suite above. | £61,000–£122,000 |
| Large (50m² plus total) | Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing. | £102,000–£184,000 |
The main things that change the figure:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Bathrooms, en-suites and plumbing on the upper floor
- Scaffolding duration, access and the level of finishes
What do you get?
- Insulated cavity walls with brick or render to match the house
- First-floor joists, stud walls and new openings upstairs
- Scaffolding for the full build, erected and inspected
- Electrics, plumbing and heating by qualified trades, with certificates
- Windows, external doors, plastering and internal doors
- Building control inspections and completion certificate
Homes in Bristol
Bristol has a strong mix: Georgian terraces and villas in Clifton and Kingsdown, rows of Victorian and Edwardian terraces across Bishopston, Totterdown and Easton, and interwar council estates on the edges. Grey-brown Pennant sandstone is a common walling stone, often with Bath stone dressings, alongside brick, render and newer apartments near the harbour.
Terraced streets often suit loft rooms and side-return extensions, plus stone repointing in lime mortar. Hillside houses can need retaining work for patios and driveways, while interwar homes commonly take rear extensions and new windows.
Exposed, west-facing slopes can catch heavy driving rain, so render, pointing and window seals on those elevations take more weather than sheltered ones.
Do you need permission in Bristol?
As Bristol is in England, read the following with that system of planning and building control in mind. We check what applies to your house with the council before you receive a 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
Book a visit and we'll come to you. The survey covers measurements, the state of what's there now and any obvious constraints, so the price that follows is based on your actual home, not an average.
Your fixed price
After the survey we send a quote for a double-storey extension that fixes the price for the scope we've agreed. If you want to change materials or scope, we revise it in writing before anything is booked.
Plan and prepare
With the quote agreed, we book the work in and handle preparation: permissions where needed, building control notifications, material orders and access arrangements for your Bristol property.
Finish and handover
Work goes ahead as scheduled and you deal with one contact throughout. When the last trade leaves, we clear and clean the site, talk you through what has been done and pass on any certificates and care instructions.
How we work
Frequently asked questions
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.
Will the extension affect my neighbours?
A double-storey extension can affect neighbours' light, outlook and privacy, which is why planning departments look closely at height, depth and window positions. Side windows facing neighbours often need obscure glass. Work near a shared wall may also need party wall notices; the Party Wall etc. Act 1996 applies in England and Wales only. We talk through these points early so the design is realistic.
What happens at the survey?
We visit your home at a time that suits you, look at the area involved, take measurements and check access, condition and any services that might be affected. We talk through what you want from a double-storey extension, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
How much does a double-storey extension cost?
A typical double-storey extension of 30–40m² across both floors costs £61,000–£122,000, built to a plastered finish. As a rough guide, allow around £1,400–£2,600 per square metre plus fixed costs for groundworks, scaffolding and fees. The second storey usually costs less per square metre than the first, because foundations and roof are shared. Bathrooms upstairs and a complex roof add most. We confirm a fixed price after the survey.
How long will a double-storey extension take?
On a typical home, allow 14–22 weeks on site. Larger projects, older buildings and extra work found once things are opened up can extend that, while simpler jobs may be shorter. Your quote includes an estimate of time on site, and your point of contact keeps you updated on the programme as the work progresses.
Towns in Bristol
We offer a double-storey extension in each of the towns below, all within Bristol. Select yours for guide prices, postcodes covered and nearby places.

