Should I Build A Granny Annexe In My Garden?

Should I Build A Granny Annexe In My Garden?

If you own a property with sufficient space in your garden to accommodate a granny annexe, you might already have considered building one for a family member. There are many advantages and disadvantages of building a granny annexe, so if you’re trying to decide whether it’s the right course of action for you, here is some helpful advice for you.

Granny Annexes – What Are They? In simple terms, 'granny annexes' are secondary buildings that are constructed away from your main house, typically in a garden, usually to accommodate elderly relatives, hence their name.

While it’s still one of the most common reasons for constructing an annexe, particularly with high fees for care homes in mind, their use has changed over the past few decades.

Now, homeowners are just as likely to build a granny annexe for their child as for their ageing parent! It’s an especially useful way for parents to give their children independence when they are struggling to get onto the property ladder.

As an added benefit, it also increases the main house’s overall value.

Do Granny Annexes Have Any Planning Rules? If you’re thinking of building a granny annexe, you’ll need to find out whether you have to apply for planning permission.

There are several factors that are taken into account, including whether the annexe will be covered by the Caravan Sites Act. If your intended annexe will be classified under the Caravan Sites Act as a mobile home, and it won’t be rented out or sold separately from your main house you may require no planning permission.

However, you’ll require a local authority Lawful Development Certificate to confirm this and to clarify the annexe will be “incidental” – this means that is seen as another of your main residence’s rooms, but in an outbuilding form.

It's wise to hire an expert in planning in situations like this, as a mistake could be expensive to rectify at a later date.

How Large Can I Make My Granny Annexe? The regulations vary between councils but in general, the footprint of any annexe cannot be bigger than that of your main house. Also, it’s likely the combined main property and annexe footprints will be considered in relation to all the land that you own. The greater the percentage you’ll be building on, the harder it is to get planning permission.

How Much Will A Granny Annexe Cost? As you’d imagine, there are many variables in the cost of building a granny annexe. The price will depend on whether you’re building it from scratch or buying a pre-designed garden portable annexe.

The size and build type will also affect the price as will the fittings and fixtures. On average, though, building a granny annexe in the Cotswolds and the Vale of the White Horse will cost you somewhere between £30,000 and £120,000.

Do I Have To Pay Council Tax For A Granny Annexe? If one of your family members lives in your annexe there will be no council tax to pay if they are dependent, or it’ll be reduced by half if they are non-dependent. If somebody lives in the annexe who isn’t one of your family members, though, the full amount of council tax applies.

If you’re thinking of buying, selling, or leasing a property, don’t hesitate to get in touch with us today.












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