Do You Need Planning Permission for a Granny Annexe? Your Ultimate Guide with AnxSpace

Are you considering adding a granny annexe to your property? Whether it’s to create a comfortable home for an elderly relative, give a young adult some independence, or explore rental possibilities, granny annexes are increasingly popular across the UK. But one question often crops up: Do you need planning permission for a granny annexe? The answer varies depending on factors like size, location, and purpose. In this comprehensive guide, we’ll cover everything you need to know about planning permission for granny annexes, with insights from AnxSpace, your go-to granny annexe planning service provider. Let’s get started!

What Is a Granny Annexe?

A granny annexe is a self-contained living space built on the same property as your main house. Typically designed for a family member—often an elderly parent or grandparent—it offers independence while keeping loved ones nearby. These annexes usually include a bedroom, bathroom, kitchenette, and living area, making them fully functional homes within your property.

At AnxSpace, we see granny annexes in all shapes and sizes: extensions to your house, conversions of outbuildings like garages, or standalone garden structures. Their versatility is a big draw, but it’s this variety that can complicate planning rules. That’s where our expertise comes in handy.

Do You Need Planning Permission for a Granny Annexe?

Simply put: it depends. Whether you need planning permission depends on how your annexe is classified under UK planning law and whether it qualifies under Permitted Development Rights. Here’s the breakdown.

1. Permitted Development Rights: When Permission Might Not Be Needed

In the UK, Permitted Development Rights (PDR) allow certain home improvements without requiring full planning permission. For a granny annexe, this could apply if it’s considered an incidental building—like a garden room—rather than a separate dwelling.

To fall under PDR, your annexe must meet these conditions:

Size Limits: It can’t cover more than 50% of the land around your original house (excluding the house itself).
Height Restrictions: Single-storey annexes must not exceed 4 metres in height (or 2.5 metres if within 2 metres of a boundary).
Location: It should be in your garden or curtilage, not in front of your home’s principal elevation.
Use: It must be incidental to your main house—not a standalone residence.

If your annexe fits these rules, you might not need permission. However, councils differ, and properties in conservation areas or listed buildings have stricter guidelines. AnxSpace recommends checking with your local authority to be sure.

2. When Planning Permission Is Required

If your granny annexe doesn’t qualify under PDR, you’ll need to apply for planning permission. This often applies when:

It’s a separate dwelling with its own utilities, address, or council tax.
It exceeds PDR size or height limits.
It’s in a restricted area like a conservation area, National Park, or Area of Outstanding Natural Beauty (AONB).
It’s a permanent structure rather than a temporary one.

For instance, if you’re building a fully equipped annexe for long-term use, your council might see it as a separate home, requiring permission. AnxSpace can help you navigate this process smoothly.

3. The Caravan Act: A Clever Option

Here’s a neat workaround: the Caravan Sites and Control of Development Act 1960. If your annexe is a mobile structure—like a prefab cabin or static caravan—it might not need traditional planning permission, as long as it’s used by a family member and linked to your main house. It must meet caravan standards:

Max size: 20 metres long, 6.8 metres wide, 3.05 metres high.
Movable (even if it stays in place).

This is a great choice for quick, affordable annexes. AnxSpace can advise if this suits your project.

How to Apply for Planning Permission with AnxSpace

If your granny annexe needs planning permission, don’t fret—it’s straightforward with the right help. Here’s how AnxSpace supports you:

Pre-Application Advice: We’ll connect with your local council for early feedback, saving you time.
Submit Your Application: We’ll handle your forms and documents, including site plans, floor plans, and a Design and Access Statement.
Pay the Fee: Costs start at around £206 in England—we’ll manage the details.
Await Approval: Councils take 8-12 weeks to decide. We’ll keep things on track.
Appeal if Needed: If refused, we can assist with an appeal to the Planning Inspectorate.

With AnxSpace, your application will highlight family benefits—like supporting elderly relatives—that councils often favour.

Beyond Planning Permission: Other Considerations

Planning isn’t the only factor. Here’s what else to think about, with AnxSpace’s expertise:

Building Regulations

Even without planning permission, your annexe might need to meet Building Regulations for safety and efficiency—think insulation, electrics, and accessibility. We ensure your build complies fully.

Council Tax

A separate dwelling could mean extra council tax, but exemptions might apply for dependent relatives. AnxSpace can clarify this for you.

Property Value

A well-planned annexe can boost your home’s worth. We design annexes that add real value.

Why Build a Granny Annexe with AnxSpace?

Here’s why a granny annexe—and partnering with AnxSpace—makes sense:

Family Ties: Keep loved ones close with independence.
Cost Savings: Cheaper than care homes or separate housing.
Flexibility: Ideal for guests, kids, or rentals (with permission).
Expert Guidance: From planning to completion, we’ve got you covered.

Get Started with AnxSpace Today

So, do you need planning permission for a granny annexe? If it’s small and incidental, maybe not—but larger or independent structures likely will. The key is planning ahead. At AnxSpace, we’re here to guide you through Permitted Development, caravan options, or full applications—whatever your project demands.

Ready to build? Contact AnxSpace today to bring your granny annexe vision to life, hassle-free!