Create the Ultimate Garage Conversion

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There are a plethora of reasons why you could consider converting your garage into a brand new space for you and your family to enjoy.

For example, your brood may be expanding and you need a new bedroom but love your current house and the area it’s in. Maybe you’ve set up a new business and need a dedicated room to focus. Also, let’s face it – few households use their garage for its intended purpose anymore – vehicles are usually parked on the roadside or in a driveway anyway.

Plus, while you’re carrying out that exciting extension and creating an additional room in your home, you can easily store your belongings currently in the garage, in a storage unit – while you decide what you want to do with them.


So what do you need to consider? This type of project is a big undertaking if you’re looking at how to convert a garage into a room yourself. You also need to think about the level of finish you are hoping for on your project, as to whether you seek outside help or DIY the whole thing.

There are also different avenues for what space you have available; for instance – integrated or attached garages can flow far more easily into and as part of your home and detached garages offer a different type of option.

An attached garage gives an excellent option for an extra bedroom, bathroom or kitchen. Or to be honest, anything you like for additional living space.

A detached garage can offer lots of options but naturally lends itself to something along the lines of an annexe, home office, gym, guest room, playroom or even (if you’re feeling fancy) a home cinema!

The average single garage offers up roughly 15m2 of floor space and a double 30m2 so you can see that both offer up ample space. But while a double garage gives you extended possibilities, you may also require planning permission depending on your intended uses for the space.

It isn’t usually required if the work is all internal, but you could encounter some red tape so make sure you check the regulations before you get started! Call your local planning department and if the response is positive, send them a letter to ask for written confirmation to make sure you’re covered.

Make sure you are super organised every step of the way. Keep on top of all the official paperwork and regulations to make sure your special project runs as smoothly as possible.

There are lots of options – so we’ve put together a comprehensive list of what you need to think about, plus pros and cons to help you make your decision on whether to convert the garage or not.

Space assessment

First and foremost, you need to carry out an assessment of the space you have to work with. If the space is currently used for storing your belongings then you will need to come up with an alternative solution.

Next, you need to assess the condition of the foundations, walls and roof to determine whether this is a viable space to begin work. Chances are these things will need some work so be prepared for that. Also, prepare yourself for the possibility that your garage is in an unsalvageable state. Demolition and replacing could be more cost-effective than renovating, in some cases.

You will always need to consult the advice of a professional when it comes to converting a garage space. An architect will need to assess any plans to extend or amend the building and a builder will need to have input on the groundwork that needs to be done and consult. However, once the experts have offered their suggestions you can then DIY – and save a lot of money!

Next, we’ve gone on to feature everything that you’ll need to consider and work on, to get the job done.

Rules and regs

You will be required to comply with Building Regulations, including sending a building notice to the council.

These regulations apply to the following:

  • Ventilation
  • Moisture proofing
  • Insulation
  • Fireproofing
  • Escape routes
  • Structural soundness

The building inspector will also visually inspect windows and doors, fireproofing and foundations before handing over a certificate of completion.

Before you get carried away

Foundations, foundations, foundations! Everything needs stripping back to basics to make it watertight and structurally sound before any other work can proceed.

Insulation and damp proofing

Walls, floors and roofs all require appropriate insulation so their own ‘U-values’ meet Building Regulations.

Damp proofing is necessary for the walls and floor. Ensure you verify whether your walls already have a damp proof course in them, as many garages do. But if yours don’t, that will need to change. You should damp proof the floor at the same time as the floor is remade by laying a damp proof membrane.

Your floor

The floor you already have in your garage will be strong enough and, as we’ve just mentioned, it will require damp proofing and insulations to meet regulations.

When it comes to flooring, your options include:

  • Concrete floor – this can be easily created and the damp proof membrane added between the two layers with insulation added under the new floor.
  • Raised timber floor – this can be built over the floor you already have and the damp proofing can be laid under the timber with insulation between raised timbers and joists of the floor. Consult fire regulations when adding a timber floor.

Plumbing and wiring

This can get complicated – if it wasn’t already! You clearly need a thorough account of the plumbing and wiring in the house and garage. Check the walls and ceiling of your garage for wiring and note that rewiring your garage to make it livable with lights and heating will place additional strain on the household mains. This might mean you need to install a separate unit. If you’re planning to install a bathroom you will need to identify the main outflows for water and soil.


Your external walls are covered by building regulations and they must hit the mark for moisture-proofing and insulation. If the garage is integrated into the house, these walls will usually meet building regulations already. If not, consider a stud wall inside the existing exterior wall to house insulation, power and water lines.

Don’t forget the interior walls and the doors through these walls will also need to meet proper fireproofing requirements.

Windows and doors

To meet building regulations you will require ventilation, should you choose to have a second room in the garage conversion. This is coupled with an escape route to comply with fire regulations. Regulations also state that a window must have trickle vents, be 1/20 the floor area of the room along with a 600mm base opening plus a total area of no less that 0.45 m2.

To simplify, windows that meet these requirements are:

  • Metal frame (must have a ‘thermal break’)
  • uPVC (find examples of uPVC windows here)
  • Wood frame windows (must be of sufficient depth to accommodate a double-glazed unit of 24mm)

Doors must meet the same requirements as windows.


As long as you’re not unlucky with structural stumbling blocks, converting your garage should save you money in comparison to adding an extension to create more space.

However, pricing relies entirely on whether you are converting a garage into a room DIY style or if you call on outside expert help. In addition, if you’re looking to put in a lot of plumbing and electrical work this will add between £2,000-£3,000 to your total bill, so that’s definitely something for you to keep in mind.

Should you choose to take on the task yourself when it comes to the cost of a single, integrated garage you could be looking at as little as £6,000 for the whole project. That works out at an impressive £400 per m2.

Detached garages could cost far more, however – up to £1000 per m2 and if you were looking at bringing in external help, take a look at this cost breakdown to help you compare.

We’re now going to try and help you weigh up the pros and cons of converting your garage to further help you make your decision!


  • Can add value to your home, providing you have alternative parking arrangements.
  • If you need more space, you can add space and value to your home and avoid the hassle of moving in the process.
  • Makes use of a space that could be going to waste.
  • Could be a rentable option to make you extra money.
  • Expands your small home.
  • A more cost-effective way to add space than building an extension.
  • Allows you to stay in an area you’re happy in and means you don’t need to move your children out of school.
  • Total design control – subject to legal restrictions, obviously!
  • The space already exists, you might as well utilise it.
  • Could be a fantastic solution for ageing parents – they get personal space on a ground floor and you can look after them when they need it.
  • If you have the money and resources it can be completed in just a few weeks.
  • It’s a brand new room you can design from scratch – exciting times!
  • Waiting on planning permission for exterior? You can still crack on with the interior while you wait!


  • Loss of storage space.
  • Have to consider future buyers if you think you may sell in the future – would they prefer to have a garage?
  • It could be disruptive and any adjoining rooms may be unusable during the conversion.
  • You are responsible for the legality of the work done and in turn, it could become time-consuming.
  • If you do need planning permission you may not receive it and will still be charged for the application.
  • Uncertainty of costs – you also may be required to pay for additional improvements or repairs.
  • Could be lots of red tape – you need to do your research
  • You could be in danger of upsetting your neighbours with the upheaval and noise.
  • While it could add value, it could actually also decrease value of your home if you don’t have ample parking space.

So what do you think? Is a garage conversion for you? If you decide to go ahead, ensure you get your hands on a completion certificate when your hard work comes to fruition. Any project that requires a building notice needs one of these to show the work met regulations. Make sure you submit the documentation to the building inspector upon final inspection. The certificate should follow within 28 days.


If you need somewhere to house your belongings while work is carried out, a storage unit is a great idea and we offer a whole host of sizes.