If you have a garage that is rarely used for parking or storage, converting it could be one of the most practical ways to create additional space in your home.
But how much does a garage conversion cost in Cambridge?
The answer depends on the size and condition of the garage, what you want to use the new room for, the amount of structural work required and the quality of the finished space.
As a broad 2026 UK guide, garage conversions are commonly estimated at around £10,000–£20,000 for a typical 16m² integrated or attached garage, although more complex projects can cost substantially more. Cambridge-specific estimates vary, demonstrating why a site-specific quotation is important.
What Is the Average Cost of a Garage Conversion in Cambridge?
A basic garage conversion can be considerably cheaper than constructing a new extension because the main structure of the building already exists.
For budgeting purposes, you may see figures in the region of:
- Basic garage conversion: around £10,000–£15,000
- Standard habitable room: around £15,000–£25,000
- Higher-specification conversion: £25,000+
- Conversion with an en-suite or more extensive plumbing: potentially considerably more
These figures are only general guides. A garage that requires significant structural alterations, drainage work or a new floor may cost much more than a straightforward conversion.
The specification also makes a major difference. Turning a garage into a simple home office is very different from creating a bedroom with an en-suite bathroom.
What Is Included in a Garage Conversion?
A professional garage conversion might involve some or all of the following:
- Insulating walls and ceilings
- Upgrading the floor
- Damp-proofing
- Replacing or infilling the garage door
- Installing windows
- Installing an external door
- Electrical work
- Heating
- Plumbing
- Plastering
- Flooring
- Decorating
- Structural alterations
- Internal walls
- Bathroom installation
- Joinery and carpentry
The more extensive the conversion, the higher the overall cost is likely to be.
What Can You Turn a Garage Into?
One of the biggest advantages of a garage conversion is its flexibility.
At Stefan’s Building, garage conversions have been used to create spaces including home offices, gyms, storage areas and additional living accommodation.
Other possibilities include:
Home Office
With more people working from home, an unused garage can provide a dedicated workspace away from the main living areas.
Bedroom
A properly converted garage can potentially become an additional bedroom, subject to meeting the relevant requirements.
Home Gym
A garage can provide a useful dedicated fitness area without sacrificing an existing bedroom or living room.
Playroom
Converting a garage into a playroom can give children their own space while keeping toys and activities away from the main living areas.
Utility Room
If your existing kitchen is short on storage and appliances, the garage could potentially become a dedicated utility area.
Guest Room
A larger garage may be suitable for creating a comfortable guest bedroom, potentially with an en-suite bathroom.
What Factors Affect Garage Conversion Costs?
The Size of Your Garage
A single garage will obviously require less work and fewer materials than a double garage.
However, the cost isn’t simply determined by floor area. Fixed costs such as design, building control, electrical installation and structural work can still apply.
The Existing Garage Floor
The existing garage floor may not meet the requirements for a habitable room.
Depending on the property, you may need to upgrade insulation, damp protection and the floor build-up.
Insulation
Garages are generally designed for vehicles rather than people, meaning they may not have the same thermal performance as the rest of your home.
A conversion therefore needs to address insulation and energy efficiency.
The Garage Door
One of the most visible changes is often replacing or infilling the existing garage door.
This could involve creating a new wall and installing a window, French doors or another suitable opening.
Plumbing
If you want an en-suite, utility room or kitchen area, plumbing can significantly increase the cost and complexity of the conversion.
Electrical Work
A habitable room will usually require appropriate lighting, sockets and potentially additional electrical circuits.
Structural Work
Some garage conversions are relatively straightforward, while others involve removing walls, altering openings or making structural changes.
A structural assessment can help establish what is required before work begins.
Do You Need Planning Permission for a Garage Conversion?
Planning permission is not usually required where the conversion is internal and the garage isn’t enlarged.
Greater Cambridge Shared Planning states that a typical garage conversion can be carried out without planning permission where the work is internal, the garage isn’t enlarged and any replacement of the garage door with a window meets the specified appearance requirements.
However, there are important exceptions.
For example, planning permission may be required if:
- You enlarge the garage
- You substantially alter the external appearance
- You create separate self-contained accommodation
- A planning condition restricts the use of the garage
- Permitted development rights have been removed
Always check the specific circumstances of your property before starting work.
Garage Conversion and Building Regulations
Even if planning permission isn’t required, Building Regulations may still apply.
A conversion into habitable accommodation needs to meet relevant standards covering areas such as:
- Structural safety
- Thermal performance
- Ventilation
- Fire safety
- Electrical installations
- Damp protection
- Energy efficiency
This is an important distinction that homeowners sometimes overlook.
Is a Garage Conversion Worth It?
For many homeowners, converting an unused garage can be a highly effective way of creating additional usable space.
It can be particularly attractive if:
- You rarely use the garage for a vehicle
- You don’t want to lose garden space
- You want to avoid a larger extension
- You need an additional room
- You work from home
- You want a gym or hobby room
A garage conversion also typically involves less construction than building a new extension.
Why Choose Stefan’s Building for Your Garage Conversion?
Stefan’s Building provides garage conversions in Cambridge and Cambridgeshire, with experience transforming garages into practical and attractive spaces.
The team can manage projects from the initial planning stage through construction and completion, with services covering structural work, insulation, electrical installation, plumbing, plastering, flooring and other finishing work.
Get a Garage Conversion Quote in Cambridge
The best way to understand the cost of your project is to have your garage assessed and receive a detailed quotation based on its condition and your requirements.
If you’re considering a garage conversion in Cambridge, contact Stefan’s Building to discuss your plans and discover how your unused garage could become valuable additional space.