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Everything You Need to Know About Garage Conversions

15 March 2022

A garage conversion is often seen as a great way to extend the indoor square footage of a property, without having to go through the hassle and rigmarole associated with a traditional extension to a building.

However, whilst you may be excited at the prospect of turning your garage into a new and viable space for the inside of your property, it can always help to have the bare facts laid in front of you regarding what you can expect in terms of planning, the build itself, and what you might be able to expect from the finished room.

So, what do you need to know about garage conversions – and where do you even start when it comes to converting your garage?

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Should I Convert My Garage?

It doesn’t matter what kind of property you have, or even if the garage itself is attached or detached from the property itself – additional habitable square footage that is linked to the property itself is always a boon to property value, raises the quality of life for those who use the property, and often improves the overall health of the garage as flaws and faults are exposed and fixed or improved as construction takes place.

You don’t even have to consider the garage separate from the property itself – with a little work, you can always extend existing rooms within your property into attached garages for an extended room. Wider kitchens, longer dining rooms or much bigger living spaces – all achieved easily through the upgrading of a garage, either as a standalone project, or as part of larger remodelling works in your home.

However, if you are thinking about converting your garage, there are a number of considerations to take into account before you dive in. First, think about whether or not you will be granted planning permission to undertake the works themselves.

Consider Planning Permissions

Converting your garage will sometimes require planning permission from the local authorities – this means unfortunately if your home is a listed building, or built within a regulated zone, that you are going to have a much harder time in getting permission to get your garage conversion project going – especially if your plans defer from the original façade or use of the garage quite significantly.

The Purpose of the Room

You also need to consider the use of the room the garage will be converted into, and whether or not the garage will actually be suitable for those purposes and if your budget can cover the cost of the conversion itself. Remember, a living space or extra dining room might only need some light electrical work doing, or maybe even modification of the electrical wiring in place within the garage already.

However, if you are planning for a more substantial conversion, like maybe turning your garage into a functional kitchen, then you could be looking at higher costs. It isn’t just costs that have to be factored into your thinking either, but also the usability of your property as the improvements take place.

So, if you were getting your garage converted into a kitchen, or a bathroom (for example) and the work renders your current kitchen or bathroom unusable? Will you be able to cope with the loss of your at home facilities for the duration of the upgrade?

Further to this, any work done you are going to be held legally responsible for. That means that if you make the decision to sell your property, you need to have all the correct documentation for electrical and plumbing work undertaken in the construction of your converted garage.

Keeping all of these documents safe, alongside the original planning permission, is vital when it comes to selling your property. This is because you will have to satisfy the searches that will inevitably crop up during the purchasing process, providing the necessary documents to prove all work carried out is legal and safe.

If you cannot provide these for whatever reason, there is every chance the potential buyer may pull out of the sale due to a lack of legal assurance that the garage conversion is all above board.

With all of that in mind, and assuming that you have considered all of the above factors and decided to go ahead with your garage conversion, what might the next step be?

Request a survey

Need a survey? call 0800 288 8660 or

Does a Garage Conversion Need Planning Permission?

Often, when conducting property improvements, extensions, or remodelling, you may require planning permission from the local authorities. However, in the case of garage conversions, you may be relieved to find out that in many cases (especially regarding integral, or connected garages), that planning permission is not required.

Instead, the works may well come under permitted development, which means you do not need to seek and have planning permission approved. However, it is definitely not advised to plough ahead with a garage conversion under only the assumption that planning permission is not required.

It is always best to consult with and retain evidence from, the local authorities to clarify that your garage conversion does or does not need planning permission.

If you don’t need planning permission (and have been told so by the local authorities), then you could look into obtaining a lawful development certificate. A lawful development certificate is a great way of covering yourself in the future, as if planning permission isn’t required but you still want to prove that the work conducted is legal and recorded, a lawful development certificate can help with that.

If your garage conversion is not covered under the definition of permitted development then you may well need to pursue planning permission for your project.

Also, if you are looking to convert a stand-alone garage that is separate from your property you may need to look into applying for a change of use – a way of alerting and noting with the local authorities that the garage will now be used for a separate purpose than its original intention.

Request a survey

Need a survey? call 0800 288 8660 or

Does a Garage Conversion Need Building Regulations?

Whilst the question of whether a garage conversion will need planning permission depends on the circumstances surrounding the garage conversion itself, it’s almost a certainty that you will require building regulations in order for the various works to be completed.

These regulations will apply to various different aspects of a structure’s safety features, including the fire safety and preparedness of the structure, the ventilation level, the thermal performance and insulation factor, and the acoustics of the inside of the structure itself.

You will have to submit a building notice to your local building control authorities, who will then register your garage conversion, and periodically check in on your project to ensure that the guidelines are being followed and adhered to.

Request a survey

Need a survey? call 0800 288 8660 or

What Work Will Need Doing on My Garage Conversion?

When it comes to actually working on a garage conversion you will find that there are a couple of jobs that nearly everyone will have to undertake.

The first of these concerns the garage floor. Commonly, in order to complete a garage conversion, the garage floor will need to be damp proofed, insulated and levelled.

This means that a damp proof specialist will need to install either a DPC, or other form of waterproofing to put a full stop to the kind of damp that could potentially ruin your carpet and see the growth and spread of dry rot and moulds.

Levelling and insulating the floor is pretty self explanatory when it comes to creating a comfortable space. So, you won’t be surprised to learn that another common job to do when it comes to garage conversions is insulating the walls and the roof as well, and then potentially covering that same insulation in plaster, or plasterboard.

These are all necessary steps in creating a successful and long lasting garage conversion, and once they are complete you will find that decorating your garage conversion to look like a proper extension of your property becomes much easier.

Of course, these are only actions that need to be taken in order to get a garage conversion in line with the rest of the property. One very common question that comes up when garage conversion are being discussed is ‘can I brick up my garage door?’

The answer is actually a pretty simple one: yes. The real issue is making sure that the masonry used to fill in the cavity left by removing the garage door is not only up to building regulations and damp proof capabilities, but in keeping with the rest of your property.

The two most common routes are as follows. You can take the opportunity to fill the garage door cavity with damp proof walling and insulation before applying an external rendering to match the rest of the properties exterior, or, using walling that matches your properties exterior to brick in what was once your garage door.

Obviously, plaster will need to be applied internally in both instances in order to decorate properly, and there are options outside of bricking your garage door shut, such as having the space filled with glazing – just be sure that the glazing you choose has adequate ventilation options to ensure that condensation and moisture doesn’t build up within the new room.

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Need a survey? call 0800 288 8660 or

Does My Garage Extension Need New Foundations

Garage extensions do not always need a brand new foundation laying in order to make them sound. It all depends on the space beneath where the door once was on the garage already has foundations installed beneath.

If so, then you may well be able to brick in a wall above where your garage door once was. If not, then you will want to speak with the technician, builder, or engineer you are consulting with over the build of your garage extension.

Request a survey

Need a survey? call 0800 288 8660 or

How Do I Insulate and Damp Proof My Garage Conversion?

If you want your garage conversion to be a comfortable and liveable space then you need to consider the insulation methods you employ to keep your space heated.

One option to consider is cavity wall insulation. Quality cavity wall insulation is placed within your walls as they are being built, potentially between the exterior brickwork and the interior plasterboard. Depending on the quality of cavity wall insulation you are using, you might find that this already conserves a lot of thermal energy easily.

You can always extend the thermal retaining qualities of your garage’s walls by using a thermally insulating coating on the walls before you decorate. Our specialised damp repelling and thermally insulating wall coating ThermalTek is a brilliant option for those looking to both retain heat within their property, whilst also maximising damp proofing effectiveness.

A coating like ThermalTek will actively repel water droplets, stopping the onset of damp, whilst also reflecting thermal energy – preventing heat from escaping in colder months.

You will also need to consider your converted garage floor. We already mentioned that a DPC would be essential in the insulation and damp proofing of your garage and that’s because in many cases a garage floor is built lower than that of the building it is attached to. With this being the case, a survey from a damp proofing expert could be appropriate to identify whether or not your property is in need of a new DPC being installed.

Of course, you may need to take it a step further and look into a form of waterproofing your garage if it has been prone to water ingress, leaks, or flooding in the past. Luckily, a qualified waterproofing engineer will be more than capable of surveying and recommending a waterproofing system that can protect your garage from water damage in the future.

You should also consider the roof of your garage when it comes to insulation and damp proofing. Obviously, insulation will need to be placed within the roof cavity if at all possible, but also consider the ventilation and breathability of your garage conversion. Insulating your garage conversion is important, but making sure that adequate airflow is allowed is vital in reducing the build up of condensation, which could in turn lead to damp in your walls and the spread of black mould through your new space.

Consider different methods of ventilation, including the installation of a positive pressure system. A positive pressure system, fitted in the loft of your property, can adequately spread a low level current of fresh air through your property, changing the pressure therein and subtly forcing warm, moisture laden air out of your home, removing the worry of damp.

Request a survey

Need a survey? call 0800 288 8660 or

Can I Add Plumbing and Electrics to a Garage Conversion?

There is absolutely no reason that you wouldn’t be able to connect your garage extension to your electric, water, or gas supply. Just make sure that you contact a relevant technician, plumber, engineer, or electrician that holds the necessary qualifications and accreditations to complete the work.

Remember, unless you are professionally certified you should not attempt to undertake any form of work involving gas, electricity or plumbing, as it can have disastrous, harmful, or even lethal consequences.

If the work is undertaken by a professional though, you could easily have your garage conversion powered and heated during its construction. You might even find that it already has power, wired into your homes supply when it was initially built.

Request a survey

Need a survey? call 0800 288 8660 or

How Do I Keep My Garage Conversion Healthy?

The best way to ensure that your garage conversion is in a good and healthy state is by having regular checks performed by qualified surveyors.

The Timberwise team can help here. Our surveyors are on hand to not only look over your garage conversion once it’s complete, or has existed for years – but to actively assist and advise during the construction process to help you make sure that your garage conversion is fully protected against damp and timber decay from the very start.

If you would like to talk to our surveyors about offering their input on your garage conversion, either during the building process, or afterwards to make sure the new conversion is protected against damp and timber decay, then call 0800 288 8660 or submit a survey request online.

We cover the entirety of Great Britain, and our team are ready to help you make the most out of your garage conversion.