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.
From Bangor, Gwynedd, Llandudno, Holyhead and Caernarfon to the quieter corners of Gwynedd, homeowners can book a free survey for a garage conversion. We look at the building, agree the scope, then send a quote in writing that fixes the cost of that scope. Work follows the rules for Wales, and our published range for Wales, £11,000–£26,000 with VAT, gives you a sense of budget before we visit.
- Guide price
- £11,000–£26,000 inc VAT
- Time on site
- 2–6 weeks on site
- Planning rules
- Wales
- Price level
- About 8% below the national guide
- Towns listed
- 4
- Survey
- Free, with a written quote
How much does a garage conversion cost in Gwynedd?
No two jobs cost exactly the same, but the ranges below give a fair picture of a garage conversion in Gwynedd. Pricing for Wales runs about 8% below the national guide, and the overall guide is £11,000–£26,000 with VAT included. We'll confirm your figure after surveying the property for free.
| Type of job | What it usually involves | Guide in Gwynedd |
|---|---|---|
| Integral single garage | A garage within the house footprint, with sound walls and a roof already in place. | £9,200–£16,500 |
| Attached single garage | A garage beside the house that may need roof, wall or floor upgrades. | £13,000–£23,000 |
| Double or detached garage | A larger or separate building, often with a shower room or kitchenette. | £20,000–£41,500 |
The main things that change the figure:
- 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 do you get?
- 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
- Electrics, heating and ventilation by qualified trades, with certificates
- Plastering, skirting and decoration-ready finish
Homes in Gwynedd
Slate defines much of Gwynedd, from quarrying villages such as Bethesda and Blaenau Ffestiniog with their stone terraces to slate roofs across the county. Bangor and Caernarfon have Victorian and Georgian streets, Anglesey has stone cottages and bungalows, and resorts such as Pwllheli and Barmouth have Victorian terraces and newer bungalows.
Stone and slate homes need breathable lime render and pointing, and slate roofs often need careful repair rather than replacement. Terraces suit loft conversions, and bungalows commonly take extensions and window upgrades.
Eryri (Snowdonia) is among the wettest areas in the UK, and exposed coasts take strong wind and salt, so render and roof details need to be robust.
Planning and building rules in Gwynedd
Which rules apply depends on where you live. For Gwynedd, the answer is Wales, and the points below reflect that; we verify them with the council before quoting.
In Wales, an internal garage conversion usually needs no planning permission unless your planning history removed those rights.
Building Regulations approval in Wales is needed for the infill wall, 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
A visit to your home
First, someone visits your home in Gwynedd 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
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.
Getting ready
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.
Finish and handover
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.
How we work
Questions about a garage conversion in Gwynedd
How much does a garage conversion cost?
A typical single garage conversion costs £11,000–£26,000, 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.
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.
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.
How much will a garage conversion cost in Gwynedd?
As a guide, expect to pay £11,000–£26,000 including VAT for a garage conversion in Gwynedd. That range is adjusted for Wales, which runs about 8% below the national guide. Where your project lands depends on size, materials, access and the condition of what is already there. We confirm a fixed price in writing after a free survey of your home.
Towns in Gwynedd
Looking for a garage conversion somewhere in Gwynedd? Start with the towns below; each links to a page with pricing for your region and coverage details.

