Garage Conversions: A Beginners Guide

Updated: May 18

If like in many UK homes, your garage is no longer being used as a place to park your car, the chances are it has turned into a rather jumbled storage space. While this may suit some homeowners, garages hold huge potential and can be transformed into much more valuable assets. From a cluttered and drab room, a garage conversion can transform a neglected space into a functioning and vibrant part of the house -in fact, a survey conducted by Virgin Money found that a garage conversion could raise house value by up to 20%.

For those interested in the project, this article will answer all the important questions and give you an idea of the build process itself.

What are the pro’s and con’s of a garage conversion?

There are a lot of pro’s to a garage conversion but serious considerations still need to be made before going ahead.

+Garage conversions are cheap and quick relative to other conversion projects, with the average cost at about £6000 and the average build time between 7 and 10 days. They are also typically non disruptive to the rest of the house.

+They can be a smart investment. Well considered projects have the potential to add between 10-20% to the value of your home.

+It can be a much simpler alternative to moving house. With a garage conversion you can add living space without having to go through the more complicated and expensive house moving process.

- If you live on a busy street with limited parking spaces, a garage conversion can actually end up decreasing house value. Careful consideration needs to be made as to where you can park consistently before any work is carried out.

-You will need to reconsider storage space. Relocating the content of your garage is often overlooked and can result in further disruption later down the line.

-Poor planning can cost you. Although the average price of a loft conversion is relatively cheap, there is potential for expenses to escalate later down the line if the basics aren’t installed correctly.

Is my garage suitable for a conversion?

Not all garages are suitable for a straight conversion. Old garages, particularly those that were built more than 25 years ago, often have inadequate structural strength and brittle foundations. To be sure, you will need to be advised by an architect or contractor as to whether your particular foundations are strong enough. If they aren't it is not unusual for garages to be knocked down and then rebuilt from scratch. However, if your garage is made of brick or block and was constructed within the last 25 years, the chances are it will be eligible for conversion without too much alteration.

In terms of adequate garage size -most single car garages in the UK are suitable for some type of conversion. If you are unsure however, it is worth asking friends, family or neighbors who have had garage conversions and comparing dimensions.

How much is it going to cost?

The cost of converting the average garage is around £6000. However there is a lot of room for variation on that price.

There are three main factors affecting price difference.

1. The type of garage that you have to begin with

Garages that are located further away from the main household tend to cost more due to the additional plumbing, electric and foundation work required. There are 3 main garage types in the UK

Integral: This type of garage is built directly into the home and is surrounded by the walls of the main property. This is the cheapest type of garage to convert with costs coming between £400 per m² and £700 per m².

Attached: This type of garage shares at least one wall with the main property. Conversion costs between £750 per m² and £1,000 per m².

Detached: This type of garage stands apart from the main house and is the most expensive type to convert with costs coming between £1,000 per m² - £1,600 per m².

2. The condition of your garage

Older and more dilapidated garages will require extra service and end up costing more to convert. The walls, roof and floor are of main concern and if they are not structurally sound or watertight, are likely to raise the overall price of your project.

3. What you are going to convert your garage into

A kitchen or a bathroom for example is going to cost more than a bedroom, gym or living room, due to the associated plumbing costs. If plumbing work is needed for your conversion, you can expect to roughly pay an extra £3000

Who do I approach for a garage conversion?

If the plans for your conversion are complex or quite ambitious, your first step should be to approach an architect, who can guide you through some creative designs and let you know what is possible. However, architects do come at a cost, and if you have a straightforward conversion idea, you can approach an experienced builder or specialist conversion company directly. The advantage of using a specialist company is that they have experience dealing with the administrative side of a conversion, are used to working to a budget and are less likely to make the basic mistakes that will cost you in the long run.

What are the key works that are completed during a garage conversion?

1. Replacing the garage door

The garage door must be replaced with a block wall, resistant against rain and wind. This is a straightforward job as it simply involves filling in the space left by the door and (if in the design) leaving room for a window.

2. Flooring

The majority of garages have rough and uneven flooring, and so need to be leveled out with a new layer of concrete. Upon this new slab you will be able to add a nice even carpet or tiled floor.

3. Wall installation and insulation

Stud walls are typically used as the internal structure of a garage conversion, with insulation packed in to increase energy efficiency. Wall types may differ slightly however depending on the type of garage that you have.

4. Door and window installation

Doors and windows are an essential part of making your garage conversion feel like a more integrated part of your home. The amount of windows and doors will be decided on during the design stage and will vary depending on what you are going to use your conversion for.

5. Roof insulation

Much like the walls, the roof will also need to be filled with mineral wool to preserve heat and save energy.

6. Utilities

The extent to which your garage will need new electrical and plumbing work will of course depend on what you intend to use your new space for. Bedrooms and living rooms shouldn’t need more than a few socket installations, while kitchens and bathrooms will require more intricate plumbing and gas pipe work.

Will I need planning permission?

Given that the majority of garage conversions only require internal work and don’t affect the structure of the building , it is likely that the project will fall under “permitted development” - meaning that you will not require planning permission. However it is still worth checking with your local planning authority as there are quite a few exceptions.

For example, if you are converting a detached garage, there are different rules and you may have to receive “change of use” permission before work can start.

Additionally some attached garages have conditions attached to them, for example, it may be stipulated in the deeds of the property that the garage must be kept as a parking space, given a limited availability of parking on the road outside.

And if you live in a listed building or a conservation area you will not have the same permitted development rights as other houses. Your architect or contractor will be able to advise you on whether you’ll need planning permission and guide you through the administration process.

Will my garage conversion be subject to building regulations?

Given that the garage undergoes a change of use, every garage conversion is subject to building regulations. To make sure you comply with building regulations your contractor/architect will either:

Need to submit a building notice.

This type of notice is used for more straightforward projects. A building notice needs be sent to your local authority at least 48 hours prior to work starting.


Submit full structural plans

This is necessary for more complex projects. Full planning drafts and are sent to your local planning authority and reviewed before work starts. If they approve your drafts, you are safe in the knowledge that if the building follows the blueprint you have sent, your project will comply with building regulations

Either way, a building inspector will come and review the conversion once it is finished and check that key works are in alignment with regulation standards.

Further questions

If you have any further questions relating to garage conversions or the Property Makeover build process, please do not hesitate to get in touch! We offer a free consultation and quote for every potential project.