build on top of single skin garage

Do you need more space in your home? One of the ways that you can do this while keeping property changes within your budget would be by building on top of your garage, essentially adding an extension. As well as providing more space, this can also elevate the curb appeal of the property.  There are a few key factors that you need to consider when extending over a garage – but is this even possible for a single skin garage? The short answer is – you’ll need a structural engineer to check as you’ll likely need extra support to build over a single skin garage. Here are a number of other factors to consider:

Do you require planning permission?

It’s worth noting that an extension on top of a garage is never going to be automatically compliant. Instead, you need to make sure that you do request planning permission and are following building regulations. 

When you make an application with your local authority, you should research the individual ‘Housing Extension Guide.’ This will provide you with the key criteria that will be used to determine whether your extension is going to be approved. 

For instance, the extension on top of the garage might need to be set back from the house front. It is also likely that it will need to match the overall details and design features that are already part of the home. 

Do note that if your home is in a particular location, then it could be held to higher standards when you attempt to gain approval. For instance, you might have a home in the open countryside. If that’s the case, then a conservation officer could also be consulted when deciding whether to approve your request. They will explore how your extension could impact the wider area. 

Once you have considered these factors, you then need to explore the building regulations for a change like this. 

Think About Regulations 

First, you need to make sure that you are thinking about the key regulations. You need to ensure that your extension meets requirements relating to everything from floor and wall separation to energy efficiency. 

Every element of an extension like this needs to be approved by the Building Control Codes as well as any local authorities in your area. 

There are various aspects relating to building regulations that must be considered including:


Do note that when you build on top of an existing structure you are always going to add more weight to the load that exists lower down. In this case that’s the garage and the designed use for a garage is important. 

Garages are only designed to store a car. So, they might only have a single skin or single brick layer. The ground around the  garage also needs to be able to hold the two storey weight. If this isn’t possible (best to check with a structural engineer) then, the ground around the garage could get damaged and there might be problems with sewers cracking as well as similar issues. 


If you are using the extension as a living area, then you will need to make sure that you are boosting efficiency levels. This can be accomplished by adding insulation at the necessary places. You could also think about making this space in your home more modern. One of the ways that you can do this is with solar panels on the roof. Through the summer, these could provide most of the energy necessary to heat this part of your home. 

Flooring And Walls

The flooring as well as the walls of your extension must be strong enough to hold the weight of the beams designed to support the extra space. You also need to think about the contents of an extension like this. They need to reach the standards of the latest fire regulations. Do make sure that you speak to your contractor about this and ensure that materials used in this new part of your home are fire proof. 

Remember, a garage is more at risk of issues with a fire compared to the rest of the home, due to what is usually stored in this area of your property. 

If you are adding a new extension on top of your garage, then a key point to consider is who is going to do the work for you. It is possible to build a fantastic extension but only if you hire the right experts for the job. 

We hope this helps you understand some of the key factors that you need to keep in mind when you are thinking about building an extension on top of your garage. Many people are eager to make this change to give themselves and their family more space. It could be a great new addition to your home, provided you meet all of the safety and building requirements stipulated by your local council.

If you’re based in the Surrey area, get in touch with our builders in Surrey and we can discuss your garage extension project with you.

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