How Much a Garage Conversion Costs in London

A large house with a double garage

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May 7, 2024

Garage conversions are an excellent way to increase your property value and create additional living space without the need for a costly extension. However, determining the cost of a garage conversion in London can be complex, as it depends on various factors such as the size of your garage, the intended use of the converted space, structural modifications required, materials chosen and labour costs.

In this guide, we have taken a look at your expected garage conversion cost.

Average Costs for a Garage Conversion in London

Total Costs

On average, you should expect to pay between £5,000 to £10,000 for a simple garage conversion. This rises to between £12,000 to £30,000 for a double garage conversion. It’s a good idea to budget between £625 and £1,250 per square metre.

The cost of an average garage conversion in London can vary significantly, depending on the specifications of the garage and your unique requirements.

Day Rates

There are a lot of day rates to take into consideration when you are budgeting for a garage conversion in London, as a range of tradesmen are likely to be needed to complete the project. This is why the day rate for a garage conversion can vary so much.

For example, if you need plumbing in your converted space, you will need to factor in the cost of a plumber at between £325 and £375 per day. But, not all garage conversions require a plumber.

On average, a kitchen fitter charges £250 to £350 per day, a joiner charges £240 to £360 per day, and an electrician £400 per day. If you need a plasterer, you should budget around £300 per day.

Hourly Rates

Similarly to day rates, it’s hard to give an average cost for the hourly rate of a garage conversion. This is because there’s a lot of variables, and some projects require more people than others.

On average, labour rates for skilled tradespeople – such as carpenters, electricians, plumbers and general contractors – in London can range from £20 to £50 per hour.

However, rates may be higher for more specialised trades or during peak seasons when demand is high. It’s important to get quotes from multiple contractors and tradespeople to get an accurate estimate for your specific project.

Types of Garage Conversion Costs

There are a range of garage types to choose from, all of which are sure to add value to your home.

Attached Garage

There are a lot of variables that impact the cost of a garage conversion, but attached garages cost between £10,000 and £20,000 to convert in London

Detached Garage

Detached garages cost between £15,000 and £25,000 to convert in London, with the size, complexity and age of the garage all impacting that amount.

Integral Garage

The cost to convert an integral garage in London is approximately £20,500, with the price varying depending on the size, age, complexity and materials chosen.

Double Garage

On average, the cost to convert a double garage in London is £45,000. This is one of the more expensive types of garage conversion, due to the size of the project.

Costs Breakdown

A house with a garage

Labour Costs

Labour is one of the most expensive aspects of converting your garage, and the exact cost will depend on the type of garage that you have. As a rough estimate, labour costs for a garage conversion in London tend to range from £1,500 to £3,000 per square metre. It’s important to note that these are just approximate figures, and actual costs may differ based on the tradesmen hired for the job.

Material Costs

There are a lot of materials needed for a garage conversion, and the cost of these can vary depending on the quality of what you are buying and how much you need. On average, you should expect to pay between £600 and £1,500 for new doors and windows. You should budget between £1,000 and £1,300 for flooring.

Waterproofing and Moisture Control

The average cost of waterproofing a garage conversion in London will vary depending on several factors such as the size of the garage, the extent of waterproofing required, and the specific waterproofing materials used. On average, you can expect to pay between £1,000 to £3,000 for waterproofing during a garage conversion in London.

Utilities and Plumbing

The cost of utilities and plumbing can vary, as not all garage conversions require the same amount of work. If you are converting your garage into either a bedroom or living space, you won’t have to do much in the way of utilities, as most garages come with electrical wiring.

However, if you’re converting into a bathroom, or working with a detached garage, the cost is likely to be higher. This is especially true if you have to install piping for water and gas. On average, you should expect to pay between £1,000 and £4,000 for utilities and plumbing.

Insulation and Ventilation

To effectively insulate your new room and prevent a surge in heating expenses, constructing stud walls within your existing garage is essential. This enables insulation materials to be installed between the old and new walls, as well as in the roof space.

Various insulation methods exist, so it’s important to carry out thorough research to determine the most suitable option for your needs. You should budget between £750 and £1,000 for insulation.

Finishes and Materials

Generally, homeowners usually spend anywhere from £5,000 to £15,000 on finishes and materials for a standard garage conversion in London. This cost includes expenses for flooring, insulation, drywall, paint, lighting fixtures, doors, windows and any other necessary materials to complete the conversion. However, costs can escalate if high end materials or custom finishes are used.

Factors That Affect Costs

Garage Size & Type

The size and type of the garage are key parts of determining the cost of a conversion. Larger garages require more materials and labour, leading to higher expenses.

Additionally, detached garages may involve more complex conversion processes compared to attached ones, which can also impact the overall cost.

Factors such as the garage’s condition and layout also play a role, as older structures often require more extensive renovations, driving up costs further.

Purpose of the Conversion

The intended use of the converted space can also influence the cost. Converting a garage into a simple storage room will likely be more cost effective, compared to creating a fully equipped home office or additional living space. The complexity of the conversion – including the need for plumbing, electrical wiring and insulation – will all impact the overall expenses.

Structural Modifications

The cost of a garage conversion is likely to be higher if significant structural modifications are needed. Structural modifications – such as adding windows, doors or partitions – can affect the overall cost.

Structural changes may involve reinforcing walls, installing support beams, or changing the roof all of which require skilled labour and specialised materials. Any alterations to the foundation or load-bearing walls will add to the complexity and expense of the project.

Materials Used

The choice of materials used in the conversion also plays a key role in determining the cost of the project. High quality materials – such as hardwood flooring, custom cabinetry and premium fixtures – will naturally have a higher price tag.

If you opt for more budget friendly materials, you can reduce costs, but this may mean compromising on the overall aesthetic and durability of the space.

Labour Costs

Labour costs make up a significant portion of the overall expenses for a garage conversion. Hiring skilled professionals – such as architects, structural engineers, contractors, electricians, plumbers and carpenters – can drive up costs.

The complexity of the project will influence the final price, as complex projects tend to require more tradesmen and skilled professionals.

If there are unforeseen complications or delays during the construction process, you may have to budget for additional labour expenses.

Uses for a Converted Garage

A man working in a home office

Home Office

Transforming a garage into a home office is a popular choice, as it offers the perfect blend of productivity and convenience. With its separate entrance and large space, a converted garage provides a quiet and secluded area away from the distractions of the main house, ideal for focusing on work.

Additional Bedroom

Converting a garage into an additional bedroom is a great way of expanding the living space within a home. By using the garage, you can accommodate a growing family, visiting guests or generate rental income via renting. A converted garage can offer a comfortable and private area equipped with essential amenities such as windows for natural light, insulation and storage.

Home Gym

With enough space and flexibility for equipment layout, a converted garage provides an ideal environment for a home gym. You can tailor the space to accommodate your fitness goals, whether that’s adding a running machine, weightlifting equipment, or creating a designated area for yoga and stretching. The privacy of a garage allows for uninterrupted exercise sessions, free from the distractions of a public gym.

Media Room or Home Theatre

With the right setup, a converted garage can replicate the ambience of a cinema, complete with comfortable seating, high quality sound systems and a large screen. This allows you, your family and friends to enjoy movie nights in a cosy and intimate setting. You could add dimmable lighting, soundproof the walls, or install a projector for a true cinematic experience.

Game Room

Converting a garage into a game room gives you a versatile space for entertainment and leisure activities. Whether it’s for hosting game nights with friends or providing a dedicated area for family fun, a game room provides endless possibilities for enjoyment and relaxation.

Wine Cellar

Turning a garage into a wine cellar gives you a dedicated space to store and showcase your favourite bottles. With its naturally cool and insulated environment, a garage provides an ideal setting for ageing and preserving wines at optimal temperatures. You could even go as far as to install climate control systems to regulate humidity and temperature levels, ensuring that your wines remain in perfect condition.

Laundry Room

Converting a garage into a laundry room offers practicality and convenience, especially for households with limited indoor space. By moving the laundry facilities to the garage, you can free up valuable square footage inside your home, whilst also creating a dedicated area for washing, drying,and ironing clothes.

Adding cabinetry and shelving can be helpful when it comes to storing detergents, cleaning supplies and linens, keeping the space organised.

Guest Suite

Making a garage a guest suite provides you with a versatile and welcoming space for accommodating overnight guests or extended family members.

By adding insulation, flooring and furniture, the garage can be transformed into a cosy retreat complete with a bedroom, sitting area and bathroom. Guests can enjoy the comfort and privacy of having their own space, whilst staying connected to the main house through a separate entrance or interior access.

Storage Room

There are few homes that could benefit from more storage space. A storage room offers you a practical solution for organising and storing household items, outdoor equipment and seasonal belongings, and a garage is the perfect place. By installing shelving units, cabinets and hooks along the walls, the garage can be optimised to maximise vertical space and accommodate a whole host of storage needs.


Converting a garage into a workshop gives you a dedicated space for pursuing DIY projects, woodworking, automotive repairs or other hobbies. By installing workbenches, tool storage cabinets and equipment racks, the garage can be transformed into a functional workspace tailored to your specific needs and requirements.

With a converted garage workshop, you can enjoy the convenience of having all your tools and equipment in one place.

Children’s Playroom

Making a garage a children’s playroom provides a lot of space for kids to explore, play and let their imaginations run wild. By adding colourful rugs, soft seating, and plenty of storage for toys and games, the garage can be transformed into a vibrant and engaging space that caters to children of all ages.

Whether it’s rainy days or play dates with friends, a converted garage playroom provides a dedicated space where kids can let loose.

DIY Vs Hiring a Professional

If you are planning on turning your garage into a functional living space, you need to decide whether you should tackle it yourself or hire a professional tradesman. There are pros and cons to both DIY and professional routes, and weighing up the benefits of each will help you to determine the best approach for your project.

The Pros of a DIY Garage Conversion

  • Cost Savings – One of the most significant advantages of the DIY approach is cost savings. By doing the work yourself, you can avoid the labour costs associated with hiring a professional tradesman.
  • Creative Control – When you are doing a DIY garage conversion, you have complete creative control over the project, allowing you to customise the space to your exact preferences and needs.
  • Learning Experience – Taking on a DIY garage conversion project can be a valuable learning experience, providing an opportunity to acquire new skills and knowledge. It’s a chance for you to develop your existing DIY skills.
  • Flexibility – There’s a lot of flexibility when it comes to handling a garage conversion yourself. You can work to your own schedule, taking breaks as needed and progressing at your own pace.

The Cons of a DIY Garage Conversion

  • Lack of Expertise – Garage conversions involve complex tasks such as electrical wiring, insulation installation and structural modifications. These all require specialised skills and knowledge. Without the proper expertise, you could make costly mistakes or compromise the structural integrity of your home.
  • Time Consuming – DIY projects can be time consuming and labour intensive, especially if you have limited experience or busy schedules. You might find that it takes longer than you thought to complete the project.
  • Potential Mistakes – Without professional oversight, you might overlook important details or fail to meet building safety requirements, resulting in unsafe living spaces. These mistakes can be expensive to fix further down the line.
  • Limited Resources – It’s likely that you have limited access to specialised tools, equipment and materials as a novice builder, which can hinder the quality and efficiency of the conversion project.

The Pros of Hiring a Professional

  • Expertise – Professional tradesmen bring years of expertise and industry knowledge to the table, ensuring that your garage conversion is completed to the highest standards and in compliance with health and safety regulations.
  • Time Saving – Hiring a professional tradesperson can save time and effort, as they will manage all aspects of the project from start to finish, giving you more time to focus on other things.
  • High Quality Workmanship – Professionals have access to specialised tools, equipment, and materials, allowing them to deliver superior quality workmanship and results.
  • Peace of Mind – By handing the project over to professionals, you can enjoy peace of mind, knowing that your property and project are in safe, capable hands.

The Cons of Hiring a Professional

  • More Expensive – The cost of hiring a professional is more expensive than a DIY approach, as it includes labour fees and overhead expenses.
  • Limited Input and Control – You could have limited input or control over the design and customisation of the space when hiring a professional contractor.
  • Relying on Others – Hiring a professional tradesman requires you to rely on others to complete the work, which may lead to delays or scheduling conflicts.

Planning Permission

Planning permission is typically required for garage conversions, due to the significant alterations involved in transforming a non-habitable space into a habitable one. Planning permission ensures that the conversion meets local building regulations and does not negatively impact the external appearance of the property or the surrounding area.

There’s a lot that is covered by planning permission including structural changes, insulation, ventilation and fire safety measures. All of these ensure that the converted space is safe and suitable for occupation.

While the cost of planning permission varies depending on the scope of the project and local regulations, it typically involves an application fee payable to the local authority. You may need to factor in costs associated with architectural drawings, surveys, and professional advice to support your planning application.

Finding Someone to Convert Your Garage

A smiling tradesman

When it comes to finding someone to convert your garage, there are several routes that you can explore.

One option is to ask friends, family or neighbours for recommendations, as word of mouth referrals can often lead to trustworthy and reliable contractors. After all, if they were happy with a tradesman’s service, the chances are that you will be too.

Additionally, you can search online directories or platforms specialising in home improvement services, such as The Page. This will enable you to read reviews and compare ratings from previous clients, gaining an insight into their experiences.

The Page

At The Page, finding the perfect tradesman for your garage conversion in London is a breeze. All you need to do is submit your enquiry, and our team of experts will meticulously match you with a curated list of tradesmen who are tailored to meet your specific needs.

Let The Page send you a free bespoke shortlist of tradespeople suited to you and your job.

Instead of scouring the internet looking for your ideal tradesman, you can relax knowing that tradesmen at The Page have been personally met and vetted, and their previous work has been assessed.

With our rigorous selection process, you can trust that you’ll be connected to the most qualified professionals in the area, all of whom are experienced and skilled enough to complete the job to a high standard.

Regardless of the method you choose to find tradesmen, it’s important to conduct thorough research and vetting to ensure you find the right person for the job.

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We also know that things can go wrong sometimes, so our promise is to be here to sort things out when they do.

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