We’ve written before about the cost of building a garage. But what if you already have a garage but want to convert it into proper living space?

A garage conversion can be a very cost-effective way of giving your family more space. A standard single garage will give you around 14m2 extra space. You could put that to very good use as another bedroom, an extra reception room, a new kitchen, playroom, office, home gym…there are lots of options. It tends to be much cheaper than converting a loft or building an extension, especially if you’re currently only using your garage to store junk (guilty!).

How much does a Garage conversion cost?

As ever, the final cost will depend on where you are in the country, the exact specification of your existing garage and the space you want to create.

However, as a guide, a standard single garage conversion will cost between £10k and £15k. If you add a kitchen or bathroom, the costs are likely to go up, depending on your tastes.

Compare that to a 3 x 4m extension which could cost upwards of £15k, and a garage conversion begins to look like a very good option.

What’s involved in a garage conversion?

In most cases, a garage conversion will be classed as permitted development so you won’t need planning permission. However, there are always exceptions, such as listed buildings, those in conservation zones or houses with special covenants in place. It’s worth double checking with your local authority before you start. Planning permission or not, you will need to comply with building regs so you will need to notify your local authority anyway.

Assuming the existing garage is structurally sound, and water tight, one of the best things about converting an existing structure, like your garage, is that you don’t need to lay new foundations or build any walls from scratch.  That helps keep costs down.

The major structural work will be around replacing the garage door with a weather-tight solution. But even this shouldn’t be too complicated. Just make sure it matches well with the rest of the garage’s exterior. You may also want to add a door between your garage and your home. Even if there is an existing door, it makes sense to reconsider whether this door is in the right place to work well with your new living area. You may want to move it as the garage changes its use.

You’ll probably need to add some windows, and potentially an external door, to make your garage feel like a living space, not just a box. The number and size will depend on your garage and its outlook, but expect to spend from £500.

It’s likely that you’ll need to insulate the floor and install a damp proof membrane to comply with building regs. You may need to pour some new concrete to even your floor out, and perhaps raise it to the same level as the rest of the house. In most cases, you’ll want to build some stud walls inside your garage, with insulation between these walls and the existing structure to make sure the space is energy efficient and complies with building regs. Floors and walls are likely to cost in the region of £1,750.

You may need to upgrade your garage roof to make sure it’s water-tight. Use tiles that match those of the main roof to make sure the finish is in keeping with the rest of your property.

Many garages already have electricity, which is a bonus. However, depending on what you’re going to use your new space for (kitchen? Bathroom?) you may need to allow up to £3k for moving pipes and/or adding new ones. You will also need to think about heating the space; you can extend your existing system into the garage or add in a separate heater.

One more thing to think about – if you are clearing junk out of your current garage to make way, where’s it all going to go? Will you need to invest in a new garden shed?!

Adding value to your home

Converting your garage into extra living space might be a good investment with the potential to add value to your home. According to property experts, it can add as much as 10% to the value of your home. But that’s not a given.

If adding value it a priority, it’s worth doing some research before you take the plunge. In some areas with little off-road parking, a garage might actually be more valuable than an extra room would.