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 offer a garage conversion throughout West Sussex, from Crawley, Worthing, Bognor Regis and Littlehampton to the smaller places in between. Each project starts with a free survey at your home and ends with a written figure, fixed for the work you choose. Because West Sussex is in England, we work to the planning system and building standards used there, and guide prices for the South East run at £13,500–£31,500 including VAT.
- Guide price
- £13,500–£31,500 inc VAT
- Time on site
- 2–6 weeks on site
- Planning rules
- England
- Price level
- About 12% above the national guide
- Towns listed
- 12
- Survey
- Free, with a written quote
How much does a garage conversion cost in West Sussex?
No two jobs cost exactly the same, but the ranges below give a fair picture of a garage conversion in West Sussex. Pricing for the South East runs about 12% above the national guide, and the overall guide is £13,500–£31,500 with VAT included. We'll confirm your figure after surveying the property for free.
| Type of job | What it usually involves | Guide in West Sussex |
|---|---|---|
| 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 |
What moves the price up or down:
- Garage type: integral, attached or detached
- Whether a shower room or kitchenette is included
- Heating method and ventilation for the new room
- Window and door choices and the level of finishes
What do you get?
- 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
- Electrics, heating and ventilation by qualified trades, with certificates
- Plastering, skirting and decoration-ready finish
Housing across West Sussex
Chichester has Georgian brick streets, Downland villages use flint and brick, and Horsham stone slabs cover some older roofs. Worthing and Bognor Regis have interwar and post-war bungalows and semis, Crawley was planned as a post-war new town, and Wealden villages to the north feature tile-hanging and timber framing.
Bungalows commonly suit loft conversions and extensions; new-town homes often take window, roofline and cladding renewal. Flint and stone properties need lime repointing, and coastal homes may need external decorating more often.
Coastal towns face salt-laden south-westerly winds, while Wealden clay inland can shrink and swell with the seasons.
Do you need permission in West Sussex?
England, Wales, Scotland and Northern Ireland each handle planning a little differently. West Sussex comes under England, covered below, and we raise any questions with the council before your quote is finalised.
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
A free survey comes first. It gives us what we need to price a garage conversion properly, including dimensions, existing materials and access for deliveries, and gives you the chance to ask anything you like.
Your fixed price
After the survey we send a quote for a garage conversion 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.
Dates and permissions
Once you accept, we agree start dates, order materials and deal with any planning, building control or neighbour notices the job needs. You'll know who is coming and when before work begins.
On site to finish
On site, the agreed plan is followed and any change is put in writing first. At completion we do a final clean, go through the snagging list with you and leave you with the relevant documents.
How we work
Frequently asked questions
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.
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 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.
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.
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.
Towns in West Sussex
Looking for a garage conversion somewhere in West Sussex? Start with the towns below; each links to a page with pricing for your region and coverage details.

