Making use of the unused space above your attached garage is a great way to add extra rooms to your home. Georgina Crothers looks at what you need to know

When extending your home, making use of any unused space within the existing floorplan is a no brainer, particularly if the outdoor area is limited. Many UK properties feature an attached single-storey garage, perfect for building over. This project could unlock a much-needed extra bedroom and/or bathroom, without requiring you to sacrifice your existing garage space garage. Of course, you could convert the garage at the same time to add even more room. Extending upwards could also save money on the cost of putting in foundations that you would shell out for a rear extension – provided those already in place are suitable for building on (more on this later).

In this guide, I look at the key factors to consider when assessing if your attached garage is suitable for building on top of, what the options are if extra support is needed, along with some big-ticket design considerations.

Is my garage suitable for extending over?

FOUNDATIONS Before you can go ahead with adding a room over your garage, you need to consider the structural elements involved, which will ultimately determine if it’s a viable option. The first key factor to consider is the garage’s foundations. These will need to be deep enough and strong enough to take the load of an additional habitable storey, and will need to stand up to scrutiny from building control. In some cases, the garage will have been built with the original house, both by the same developer. This is the ideal scenario, as they are likely to have the same foundations.