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.
Getting a garage conversion right in Heston starts with understanding the house you already have: its age, how it was built and what has been altered over the years. We survey first, then commit on paper to a price that holds as long as the scope stays the same. Across London, guide prices run at £15,500–£36,500 including VAT, and homes in Hounslow, Isleworth and Southall are covered too.
- Guide price
- £15,500–£36,500 inc VAT
- Time on site
- 2–6 weeks on site
- Postcodes
- TW3, TW4, TW5, TW7 and UB1
- Planning rules
- England
- Local area
- Greater London
- Survey
- Free, with a written quote
How much does a garage conversion cost in Heston?
The costs listed here are typical for a garage conversion around Heston and include VAT. They reflect labour and material costs in London, about 30% above the national guide, giving a range of £15,500–£36,500. Exact pricing depends on your home, so we only fix it once a free site survey is done.
| Type of job | What it usually involves | Guide in Heston |
|---|---|---|
| Integral single garage | A garage within the house footprint, with sound walls and a roof already in place. | £13,000–£23,500 |
| Attached single garage | A garage beside the house that may need roof, wall or floor upgrades. | £18,000–£32,500 |
| Double or detached garage | A larger or separate building, often with a shower room or kitchenette. | £28,500–£58,000 |
What moves the price up or down:
- 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
What does the job include in Heston?
- 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
- New internal door or opening into the house
- Plastering, skirting and decoration-ready finish
- Building control inspections and completion certificate
Local housing and a garage conversion
London's housing is dominated by Victorian and Edwardian terraces, often in yellow London stock brick, with Georgian terraces in central districts and mansion blocks across many inner areas. Outer boroughs have large belts of interwar semis, and there are extensive post-war council estates. Many houses have been split into flats, and conservation areas are widespread.
London Clay shrinks and swells with the seasons, and street trees close to houses can contribute to movement, which affects foundation design.
Knowing the typical building types in London helps, but a survey of your own home in Heston is what decides the right approach to a garage conversion.
Planning and building rules in Heston
For anyone in Heston, 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, 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
Free site survey
We begin by looking at the job in person. During the free survey we discuss options, materials and budget for a garage conversion, and photograph or measure anything the quote needs to reflect.
Price and scope agreed
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
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
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 Heston: questions
Can I keep some storage space?
Many people keep part of the garage for storage by building a dividing wall, leaving a smaller store at the front behind the existing door and converting the area behind into a room or utility. This keeps the look of the house unchanged and gives you somewhere for bikes and tools. The converted part still needs the same insulation, ventilation and fire separation.
Who do I deal with during the job?
One point of contact manages your project from survey to handover. They schedule the trades working under our contract, keep you updated on progress, and are the person to call with any question. You don't need to coordinate builders, electricians or decorators separately, because that is part of what we do.
Will losing the garage affect parking?
Losing a garage can matter if your street has parking pressure or your property deeds or planning conditions require off-street parking. Many garages are too narrow for modern cars, so in practice the driveway often provides the parking anyway. We check for planning conditions affecting the garage before quoting. If you need extra parking, we can also price a driveway extension.
Does the floor need raising?
Garage floors are usually lower than the house floor and slope towards the door for drainage. Most conversions raise the floor with a damp-proof membrane, insulation and either a screed or a timber floor, so it lines up with the house and removes the step. The final level depends on ceiling height and the door into the house. We measure both during the survey.
Which postcodes in Heston do you cover?
We cover TW3, TW4, TW5 and TW7, along with the rest of London. 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.
Near Heston
Our coverage in Heston includes TW3, TW4, TW5 and TW7. We also travel to Hounslow, Isleworth and Southall, so neighbouring addresses are looked after on exactly the same terms as those in town.

