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Our complete guide to building an annexe in the garden

Annexes are one of the most popular areas of property investments, and it’s easy to see why.

The benefits that annexes offer are unique, and include everything from increasing the value of your property, to getting young people on the property ladder, and providing the opportunity to create a completely bespoke, personalised expansion of your home.

With an annexe, you can design a brand new, customised and completely private living area, for young or elderly relatives.

What’s more, the majority of gardens are ideally suited to the addition of an annexe.

One of the most common reasons why people are hesitant about buying an annexe is that they are concerned that they don’t have the right style or size of garden. But actually, an annexe provider like iHus can work with a huge range of outdoor spaces, and a solution can be found for almost any garden.

So, to help you determine whether or not building an annexe in the garden is the right investment for you, we’ve answered all of your most common FAQs, in this complete guide to garden annexes.

Can I build an annexe in my garden?

Although this is a question that we get asked a lot, what many of our customers are surprised to learn is that the majority of gardens are suitable for annexes to be built on them.

Annexes are precisely designed to be built in domestic gardens and onto existing properties. As a result, they are extremely flexible and can accommodate a wide range of different settings and situations.

If you’re debating how suitable your garden is for an annexe, we suggest considering the following factors:

  • The size of your garden – although your garden certainly doesn’t need to be huge, you need to make sure that you have enough space in your garden that, if you do add an annexe, your garden’s aesthetics and usability won’t be affected. We’ll cover this point in more detail later on.
  • The layout of your garden – think about how your garden is laid out. Do you have a conveniently located space in your garden, where an annexe could sit? Ideally, you’d want to choose a corner of the garden, or a tucked-away area, rather than in the centre of your lawn.
  • The purpose of the annexe – annexes can be used for a huge range of different purposes. These include everything from elderly living to offices, and first homes for young people, to accommodation for guests. So, your intended purpose for the annexe will naturally determine your specific requirements for it, and whether or not your garden is able to accommodate it.
  • Environmental factors – in some cases, a garden might be prone to environmental factors, which could make an annexe a risky investment. Common examples of this are flooding areas, a case of Japanese knotweed, or close proximity to weaker or unstable trees.
  • Any building regulations in your area – we’ll provide more detail on this point below.
  • Your plans for the future – then, personally, you need to think about what your plans are for the property. How long do you think you’ll live there? This will impact whether you want to perceive an annexe as a long-term investment for your own quality of living, or if you want to use the annexe as a way to increase the value of your property.

But, what about cases where it might be tricky to build an annexe? Are there any instances where you might want to reconsider investing in an annexe?

Examples of instances where it could be difficult to build an annexe in your garden include:

  • If your garden is too small to accommodate an annexe (keep reading for our breakdown of how much space you need in your garden for an annexe)
  • If your garden is an unusual shape, which means there isn’t an area large or flat enough for an annexe
  • If your garden is prone to flooding
  • If your garden does not offer access to utilities
  • If your chosen garden area would cause issues with property boundaries or neighbouring houses
  • If planning permission gets refused, or specific regulations or laws prevent an annexe from being built in your garden (we’ve outlined more details on how to find out about local regulations below)

If you’re unsure about whether your garden would be suitable for an annexe, or if you would like expert guidance about the best space in your garden for an annexe, you can book a free consultation with iHus.

Annexe customers stood talking to iHus staff members in their home.

Do I need planning permission for an annexe in my garden?

If you are building an annexe in your garden, you will need to obtain permission from your Local Planning Authority (LPA).

If someone is living in your annexe on a day-to-day basis, you will need approval from the LPA, either in the form of planning permission or a Certificate of Lawfulness.

In the case of most ‘straightforward’ annexes, you can achieve this through the process of a Householder’s Planning Application route. This is the standard course of planning permission, which you would take if you were building a house extension, for example.

But, if your LPA deems your annexe to be a new dwelling, then you will need to complete a Full Application.

Planning approval can only be granted once you’ve completed all your LPA’s requirements, and answered any concerns that the Local Planning Office that is managing your application has raised.

If you aren’t sure whether you will need planning permission for your annexe, then speak to one of our experts, and we will offer you a free on-site consultation service, which covers all of these bases. With a planning permission success rate of over 90%, our iHus experts will maximise the likelihood of your application being successful.

If you have any further questions about the legalities surrounding building an annexe in the garden, you can find our full guide to gaining annexe planning permission.

How much space do I need for an annexe in my garden?

Of course, this is very much like asking, ‘how long is a piece of string?’. The answer depends on how big the annexe is that you want to build!

But, you can choose an annexe type based on the amount of space that you have available.

Annexes are available in a huge range of different sizes, meaning there’s something out there to suit almost every garden.

If you take our range as an example, The Bawtry is one of our most popular one-bedroom annexes. It is a very convenient size, at 7.05m long and 5.05 metres wide. This makes it an ideal choice for most gardens.

Our entire range of annexes are precisely designed for back gardens, and include a wide variety of annexe shapes and sizes.

When deciding on the size of your annexe, you will also need to consider the requirements of your LPA, and whether your Local Planning Office has any restrictions in place regarding annexe sizes.

In fact, one of the most common reasons for an annexe application to be rejected is if the annexe is too large for the garden.

So, if you are unsure about whether your preferred annexe is a suitable size for your garden, make the most out of our free consultation service. Our expert team can share their specialist guidance, and help you to find the best annexe for your specific garden.

What does an iHus annexe look like?

iHus is the UK’s leading annexe specialists, being renowned for the chic design and flexible, bespoke builds of luxury annexes.

We have worked with property owners across the UK, to create personally tailored annexes that tick all of their unique boxes.

Our range includes a huge variety of annexes, designed to suit every individual style, budget, available space and intended use.

You can even explore some of our annexes for yourself, by visiting one of our Open Hus show annexes.

To find out more about iHus annexes, or to book a free consultation for your garden, our professional team are on hand to help.

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If you would like to download our annexe brochure please complete the form below. You call also request for a copy to be posted to your home address. Have any further questions, why not request one of our team get in touch?