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 Caernarfon and the wider Gwynedd. 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 Wales is £11,000–£26,000, VAT included.
- Guide price
- £11,000–£26,000 inc VAT
- Time on site
- 2–6 weeks on site
- Postcodes
- LL55
- Planning rules
- Wales
- Local area
- Gwynedd
- Survey
- Free, with a written quote
Garage conversions prices in Caernarfon
To help you plan, we show what a garage conversion typically costs in Caernarfon instead of holding figures back for a sales call. The range is £11,000–£26,000 with VAT, using rates in Wales that are about 8% below the national guide. A free survey then fixes your actual price.
| Type of job | What it usually involves | Guide in Caernarfon |
|---|---|---|
| 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 |
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
- 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 control inspections and completion certificate
What are homes like around Caernarfon?
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.
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.
That variety is why a guide price for a garage conversion in Caernarfon is only a starting point; the survey shows what your particular property needs.
Do you need permission in Caernarfon?
As Caernarfon is in Wales, read the following with that system of planning and building control in mind. We check what applies to your house with the council before you receive a quote.
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.
How does the job run?
Free site survey
It starts with a survey at the property, free of charge. We check condition, access and services, ask how you want the finished result to look, and answer any questions you have about a garage conversion.
Quote in writing
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.
Plan and prepare
With the quote agreed, we book the work in and handle preparation: permissions where needed, building control notifications, material orders and access arrangements for your Caernarfon property.
The work itself
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.
What you can expect from us
Questions about a garage conversion in Caernarfon
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.
How much will a garage conversion cost in Caernarfon?
As a guide, expect to pay £11,000–£26,000 including VAT for a garage conversion in Caernarfon. 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.
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 £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.
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.
Also covering areas around Caernarfon
We welcome enquiries from all LL55 postcodes in Caernarfon, plus Bangor, Gwynedd, Holyhead and Llandudno. Each one gets the same survey at no charge and a written price fixed for the work described.

