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.
We arrange a garage conversion for homeowners in St Austell and the wider Cornwall. The job is planned, priced and managed by us and carried out by tradespeople engaged under our contract, so there is one agreement and one contact. On a typical home the work takes 2–6 weeks on site, and guide pricing in the South West is £12,000–£28,500, VAT included.
- Guide price
- £12,000–£28,500 inc VAT
- Time on site
- 2–6 weeks on site
- Postcodes
- PL25
- Planning rules
- England
- Local area
- Cornwall
- Survey
- Free, with a written quote
Garage conversions prices in St Austell
The table below shows guide prices for a garage conversion in St Austell. They are based on rates in the South West, which run about 2% above the national guide, giving an overall range of £12,000–£28,500. All figures include VAT and are firmed up after a free site survey.
| Type of job | What it usually involves | Guide in St Austell |
|---|---|---|
| Integral single garage | A garage within the house footprint, with sound walls and a roof already in place. | £10,000–£18,500 |
| Attached single garage | A garage beside the house that may need roof, wall or floor upgrades. | £14,500–£25,500 |
| Double or detached garage | A larger or separate building, often with a shower room or kitchenette. | £22,500–£46,000 |
Your price depends mostly on:
- Garage type: integral, attached or detached
- Condition of the floor, walls, roof and foundations
- Heating method and ventilation for the new room
- Window and door choices and the level of finishes
Scope of the work
- Infilling the garage door opening with insulated wall and new window
- Foundation checks under the door opening and footings where needed
- Insulated walls and ceiling built to building regulations
- New internal door or opening into the house
- Plastering, skirting and decoration-ready finish
- Building control inspections and completion certificate
What are homes like around St Austell?
Older Cornish homes are often built of granite or slatey local stone, with slate roofs and sometimes slate-hung walls facing the weather. Cob cottages survive in places, Truro and Falmouth keep Georgian and Victorian streets, and many towns have rendered post-war houses, bungalows and newer estates on their edges.
Stone and cob properties often need breathable lime render, careful repointing and roof repairs. Post-war and newer homes commonly benefit from new windows, roofline renewal, external rendering and single-storey extensions.
If your house in St Austell fits one of these patterns, it helps us anticipate what a garage conversion will involve, though we always confirm the details on site.
Planning and building rules in St Austell
Because St Austell falls under England's rules, the guidance below is the version relevant to you. Before sending a price, we check your property's position with the council.
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.
The four stages
Survey and measure
First, someone visits your home in St Austell to see the space, take measurements and note anything that could affect the work, such as access or the condition of what is there. There is no charge for this visit.
Written quote
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.
Plan and prepare
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.
Build and hand over
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.
Why homeowners choose us
Garage conversions in St Austell: questions
Do I need planning permission for a garage conversion?
Whether a garage conversion needs planning permission depends on the works, your home's location, whether it is listed or in a conservation area, and which UK nation you are in. In England, converting an integral or attached garage is often permitted development where changes are mostly internal, unless a planning condition has removed those rights, which is common on newer estates. We check what applies before quoting.
How much does a garage conversion cost?
A typical single garage conversion costs £12,000–£28,500, 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.
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.
Do I need planning permission in St Austell?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. St Austell 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.
How long does a garage conversion take?
A straightforward integral garage conversion usually takes two to four weeks on site. Attached garages that need roof or wall upgrades, and conversions with a shower room, typically take four to six weeks. Detached garages turned into annexes can take longer. Before work starts, allow time for drawings and building control approval. We give you a clear programme with your written quote.
Nearby towns
Homes across PL25 in St Austell are within our coverage, as are those in Truro, Newquay and Falmouth. If you are just outside these areas, ask anyway, because we work right across the UK.