A single-storey extension is a new ground-floor room built onto your house, usually at the rear or side, with its own foundations, walls and roof, creating a bigger kitchen, living space or bedroom without moving home.
Looking for a single-storey extension in Gloucestershire? We organise the whole job, bringing in the trades it needs under one agreement, and you have a single contact. We cover Gloucester, Cheltenham, Stroud and Kingswood, along with villages and suburbs nearby. The rules in England decide what consents are needed, and our guide range of £35,500–£76,000 including VAT gives you a realistic starting point for a budget.
- Guide price
- £35,500–£76,000 inc VAT
- Time on site
- 10–16 weeks on site
- Planning rules
- England
- Price level
- About 2% above the national guide
- Towns listed
- 8
- Survey
- Free, with a written quote
How much does a single-storey extension cost in Gloucestershire?
Every figure below is a guide for a single-storey extension in Gloucestershire, inclusive of VAT. Regional pricing for the South West works out about 2% above the national guide, and the overall span is £35,500–£76,000. The survey costs you nothing, and after it we commit to a firm price for your specification in writing.
| Type of job | What it usually involves | Guide in Gloucestershire |
|---|---|---|
| Small extension (8–12m²) | A modest rear or side extension, such as a utility room or a slightly larger kitchen. | £22,500–£41,000 |
| Typical rear extension (15–25m²) | A kitchen-diner or family room with bifold doors and a rooflight or lantern. | £35,500–£76,000 |
| Large or wrap-around (30m² plus) | A wrap-around or wide rear extension, often with structural steelwork into the house. | £71,000–£133,000 |
The main things that change the figure:
- Roof type, rooflights, lanterns and the amount of glazing
- Ground conditions, foundation depth and drains to divert
- Steelwork needed to open into the existing house
- Finishes, kitchen, flooring and heating specification
What’s included?
- Groundworks, foundations and below-ground drainage
- Cavity walls built and insulated to building regulations
- Flat or pitched roof, with rooflights or a lantern if specified
- Electrics and plumbing by qualified trades, with certificates
- Plastering, screed floor and internal doors
- Building control inspections and completion certificate
Homes in Gloucestershire
Golden Cotswold limestone defines towns and villages such as Cirencester, Stow and Tetbury, often with stone-slate roofs. Cheltenham is known for Regency stucco terraces and villas, Gloucester has Victorian brick terraces and interwar estates, the Stroud valleys have mill-era stone cottages, and the Forest of Dean uses its own sandstone.
Cotswold stone homes often need lime pointing, stone repairs and windows that suit conservation areas. Regency houses may call for render and decorating, while brick terraces and estate homes suit loft rooms and extensions.
The Cotswold escarpment is exposed to wind and rain, while low ground along the Severn has a well-known flood risk.
Planning and building rules in Gloucestershire
For anyone in Gloucestershire, the relevant framework is England's. The summary below is general, so we always contact the council about your address before putting a price in writing.
In England, many single-storey rear extensions are permitted development: typically up to 3 m deep on a semi-detached or terraced house and 4 m on a detached house, no more than 4 m high, and covering no more than half the land around the original house. Larger rear extensions can go through the prior approval process. Side extensions, flats, listed buildings, conservation areas and homes where permitted development rights have been removed need planning permission.
Building Regulations approval is needed for almost every extension, covering foundations, structure, insulation, drainage, ventilation and fire safety. If the work is on or near a shared wall or boundary, the Party Wall etc. Act 1996 may apply.
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
We look at the job
A free survey comes first. It gives us what we need to price a single-storey extension properly, including dimensions, existing materials and access for deliveries, and gives you the chance to ask anything you like.
Price and scope agreed
We turn the survey notes into a written quote. The price is fixed for the specification we agree, and the document sets out materials, scope and payment stages in plain language.
Booking the work
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 Gloucestershire property.
The work itself
During the work we protect the areas around it and tidy up at the end of each day. Once complete, we check the finish, remove our materials and hand over paperwork such as building control sign-off where it applies.
What you can expect from us
Questions about a single-storey extension in Gloucestershire
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 single-storey extension, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
How long does a single-storey extension take to build?
A single-storey extension usually takes 10–16 weeks on site, from digging foundations to final plastering. Bad weather, deep foundations or a complex roof can add time. Before work starts, allow several weeks for drawings, structural calculations and building control approval, and longer if planning permission is needed. We give you a stage-by-stage programme with your quote so you know what happens each week.
Do I need an architect for an extension?
You need proper drawings for an extension, but not always a full architect service. A designer or architectural technician can produce planning and building regulations drawings, and a structural engineer provides beam and foundation calculations. If you already have drawings, we price from them. If not, we can arrange the drawings and calculations as part of the project so everything is coordinated from the start.
Do I need planning permission in Gloucestershire?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. Gloucestershire is in England, so England's rules apply. Many smaller jobs need no planning application, but some still need building control approval. We check what applies to your address before quoting.
What does a typical extension build look like week by week?
A typical single-storey extension follows the same order: clearing the site and digging foundations, building walls up to roof level, then fitting the roof and windows to make it weathertight. Electrics, plumbing, insulation and plastering follow. The last stage is opening into the house, laying the screed and fitting doors and finishes. Building control inspects at key stages, and we book those visits for you.
Towns in Gloucestershire
Our coverage for a single-storey extension in Gloucestershire includes the towns listed here. Each page explains guide costs, typical timings and the neighbouring places we also serve.