How to Plan your Garage Conversion Granny Annexe

If you’ve got an elderly relative that could benefit from living closer to you, you might be considering converting your garage into a granny annexe.

There are plenty of benefits to converting your garage into an annexe, including:

  • You’ll increase the value of your property
  • You can keep an eye on your relative’s health
  • It will reduce loneliness common in older people
  • There is no longer a council tax burden on homes with annexes

So if you’ve decided that you are going to go ahead and build a granny annexe, take a look at these things to consider to help you plan your garage conversion.

As long as you cover all the bases, you’ll create a peaceful area for your family member to live in their own space but with support from you when they need it.

Suitability of your garage

How far away from the house is your garage? Will your relative need to move to and from areas? How mobile is your relative? These are some of the things you should consider.

granny annexe
This kitchen is perfect for a wheelchair user. Image via HomeLodge
You’ll need to make sure that the garage can accommodate the elderly person’s changing needs as they get older.


Are there design elements you’ll need to consider? Will you need to install wider doors and low thresholds to allow for wheelchair access?

It’s also worth considering sensory needs as well as physical. Does your family member have dementia? If they are often found wandering, it might be useful to see what measures you can take to stop this from happening near busy roads.

Independent living technologies are also important features to consider. These include grab rails and step-free showers.

The value a granny annexe will add to your property

Although this will be the last thing on your mind when you’re caring for a relative, it is not selfish to consider the value you will add to your property by adding an annexe.

Do some research online to find out what properties with annexes in your area are going for. You could even ask an estate agent to come round and give you a rough estimate.

Whatever your reasons for converting your garage into a granny annexe, make sure it’s fit for purpose. And once you’ve worked out what you’re going to need in the annexe, get in touch with at least 4 builders to give you a quote so you can compare and find the best deal. For information on planning permission and building regulations, click on the links to read our guides.

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Approx. £12,000

Construction time

1 week - 1 month

Depending on scale and scope

Advantages and disadvantages
  • Increase your property’s value
  • Keep an eye on your relative’s health
  • Combats loneliness in older people