A garage conversion turns an integral or attached garage into a warm, habitable room by insulating the floor, walls and ceiling, replacing the garage door with a wall and window, and adding heating, lighting and finishes.
If you have a garage conversion on your list for a property in Southampton, we can help from the first measurements to the final clean-up. For a typical home, plan for 2–6 weeks on site, though larger or more complex jobs take longer. We cover postcodes SO14, SO15, SO16 and SO17 and nearby Hythe, Totton and Eastleigh, and every quote we send is fixed for the scope described in it.
- Guide price
- £13,500–£31,500 inc VAT
- Time on site
- 2–6 weeks on site
- Postcodes
- SO14, SO15, SO16, SO17 and SO18
- Planning rules
- England
- Local area
- Hampshire
- Survey
- Free, with a written quote
How much does a garage conversion cost in Southampton?
The table below shows guide prices for a garage conversion in Southampton. They are based on rates in the South East, which run about 12% above the national guide, giving an overall range of £13,500–£31,500. All figures include VAT and are firmed up after a free site survey.
| Type of job | What it usually involves | Guide in Southampton |
|---|---|---|
| Integral single garage | A garage within the house footprint, with sound walls and a roof already in place. | £11,000–£20,000 |
| Attached single garage | A garage beside the house that may need roof, wall or floor upgrades. | £15,500–£28,000 |
| Double or detached garage | A larger or separate building, often with a shower room or kitchenette. | £24,500–£50,000 |
Your price depends mostly on:
- Garage type: integral, attached or detached
- Condition of the floor, walls, roof and foundations
- Whether a shower room or kitchenette is included
- Window and door choices and the level of finishes
What does the job include in Southampton?
- Infilling the garage door opening with insulated wall and new window
- Foundation checks under the door opening and footings where needed
- Damp-proof membrane, insulated floor and screed or raised timber floor
- Insulated walls and ceiling built to building regulations
- New internal door or opening into the house
- Plastering, skirting and decoration-ready finish
Building in Southampton
Southampton and Portsmouth have dense Victorian terraces, with plenty of post-war rebuilding after wartime bombing. Winchester keeps Georgian and medieval streets, Basingstoke expanded rapidly with 1960s and 1970s estates, and New Forest villages feature cob, thatch and brick. Brick and flint is common on the chalk downs, and new estates ring most towns.
Terraces suit loft rooms and side-return extensions; post-war and expanded-town homes often need window, roofline and cladding renewal. Cottages in the Forest may call for lime repairs and planning-sensitive windows.
So when we survey a Southampton property for a garage conversion, the first step is working out how it was built and what has been changed since.
Do you need permission in Southampton?
Southampton 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, converting an attached or integral garage into a room usually needs no planning permission, unless a planning condition on your estate has removed permitted development rights (common on newer houses). Changing the garage door to a wall and window is generally fine.
Building Regulations approval is needed: foundations for the infill wall, a damp-proof course, insulation, ventilation and fire safety.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
What happens after you get in touch?
A visit to your home
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
Next you receive a written quote with a fixed price for the agreed specification. It lists what is included, what is not, and how payments are staged, so you can compare it properly.
Getting ready
Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for a garage conversion are in place before the first day on site.
Build and hand over
The work is carried out to the agreed specification, with floors and furniture protected and the site kept tidy. At the end we clean up, walk through the finished job with you and hand over any certificates.
Why homeowners choose us
Frequently asked questions
How much does a garage conversion cost?
A typical single garage conversion costs £13,500–£31,500, depending on whether the garage is integral, attached or detached and what the room is for. Integral garages usually cost least because the walls and roof are already sound. Adding a shower room, upgrading a flat roof or levelling a sloping floor adds cost. As a guide, allow roughly £550–£1,100 per square metre plus fixed costs. We confirm a fixed price after the survey.
Which postcodes in Southampton do you cover?
We cover SO14, SO15, SO16 and SO17, along with the rest of Hampshire. If your postcode is not listed, get in touch anyway: our coverage is UK-wide, and we can usually arrange a survey wherever you live. Enter your postcode in the guide-price tool or contact form and we will confirm.
Can I stay at home during the work?
In most cases, yes. Most people can live at home throughout, and we plan the work to keep disruption down by protecting floors, agreeing working hours and keeping access routes clear. Bigger jobs affecting kitchens, bathrooms or heating may mean a short spell with reduced facilities, and we talk this through with you at the survey.
Will the new room be warm enough?
A converted garage can be as warm as any other room in the house, provided the floor, walls and ceiling are insulated to current standards. Garages are usually built with single-skin walls and no insulation, so this work matters. Heating can come from a new radiator on your existing system, underfloor heating or an electric heater, depending on your boiler capacity. We advise on the most suitable option.
Will I need building regulations approval?
A garage conversion needs building regulations approval because the space becomes a habitable room. Building control checks that the new wall in the door opening has proper foundations, that the floor has a damp-proof membrane and insulation, and that walls and ceiling meet insulation standards. Ventilation, fire safety and escape routes are also checked. In Scotland a building warrant is normally needed before work starts.
Near Southampton
Coverage for Southampton spans SO14, SO15, SO16 and SO17. Close by, Hythe, Totton and Eastleigh are covered too, and the rest of our UK-wide area follows the same survey-then-quote process from start to finish.

