Granny Annex FAQ | Planning, Costs, Heating, Construction...

If you’re considering a granny annexe for you or a loved one, it can be hard to know where to start. Elderly care tends to be the driving factor behind most annexe projects, and the whole family needs to agree prior to making such a commitment.

So, with this being one of the most significant purchases you’re likely to make, please read our list of quick-fire granny annexe Frequently Asked Questions to learn more about garden living, and help you make the right decision for you and your family.

Granny Annex Planning Permission

Will I need to obtain planning permission for one of your annexes?

If a building is used for habitation with all the main services, a kitchen, bathroom and bedroom, then yes. This can be done with either householder applications or the ‘Caravan Act’. Either one requires approval from your Local Planning Authority (LPA), which we can obtain on your behalf.

What’s the difference between planning permission and the ‘Caravan Act’?

Planning permission is development of land, whilst the Caravan Act relates to the use of land. Both are decided by your local LPA.

Do you guarantee planning permission?

No, nobody can guarantee that, and it really depends on the merit of each application. Our planning consultant specialises in annexe applications and has over a 90% success rate in both England and Wales.

Do annexes need to adhere to Building Regulations?

Most annexes are built as ‘mobile homes’, and as such, they don’t fall under Building Regulations. That said, at Family Annexe we ensure that all of our annexes are put through Building regulations for added peace of mind.

How long does it take to obtain permission to build?

In our experience, it typically takes around 12-weeks to obtain permission via a householder application or via the Caravan Act. Every planning application has to be dealt with within 8 weeks of your planning application being verified by your LPA (a process, which can take up to 4-weeks itself). When LPAs are busy, time extensions can often be requested.

I live in a listed building. Can I have a garden annexe?

Yes you can. Some external materials may have to be adapted to pacify your conservation officer (i.e. adapting Thermowood cladding to untreated oak), but many annexes have been built in the gardens of listed properties.

My garden is in a conservation area. Can I have an annexe?

Yes, it’s quite possible. Our team have plenty of experience when it comes to planning, and we can usually find the perfect solution that provides you look you desire whilst adhering to local conservation guidelines.

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Granny Annexe FAQs: Finances

How much does an annexe cost?

Our pricing is extremely transparent. Everything is included within the price barring wetroom upgrade (£1,500), pitched roof upgrade (priced per model), or any site preparations prior to the groundworks. The Bluebell is our entry-level one-bedroom annexe, which costs £64,450. This price includes everything detailed within our specification, as well our fully-managed planning service. Our two-bedroom annexes start from £92,450, with our largest model being prices at £109, 450 including planning application.

What are your payment terms?

We take a £2,500 non-refundable payment for our planning service when you initially place your order. This fee is deducted from the overall cost of your annexe, and we then split the remaining balance into four payments.
The first is due once we obtain planning permission and book your build slot.
The second is due on week two of your build — once groundworks are complete and your annexe materials arrive on site. The third payment is due once all internal walls have been plastered. And the final payment is due just before we hand over the keys, subject to your approval.

Can I sell my annexe as a separate dwelling in future?

No, we’re afraid not. Planning permission will state that the annexe must remain ancillary to the main house and can never be sold separately.

Will I pay council tax on my garden annexe?

Probably not. Annexes are exempt from council tax as long as it forms part of the main home and the person living in it is a dependent relative.

Will an annexe add value to my property?

Yes, without question. A garden annexe adds value to a property by providing at least one extra bedroom and bathroom. “House with annexe” is a growing trend online with estate agents, as potential buyers can turn it into a holiday let or spread their own family out.

Are your annexes cost-efficient to run?

Yes, they’re comparable with a small new build home. The timber structure is super-insulated and uPVC windows are A-rated. We install digital electric radiators, which when properly calibrated, are extremely efficient. Water, gas and/or electric are all fed from the main dwelling.

Can my annex have a kitchen?

Yes you can. We supply a choice of kitchen cabinets, handles and worktops from Howdens, and you can pick from a range of colours.

Do you provide bathroom fixtures and fittings?

Yes, each annexe comes with a fully-fitted shower room and additional ensuite facilities in our larger two bedroom annexes.

Can I have a wetroom?

Yes, we can install a wet room instead of shower room for an extra £1,000.

Does it cost extra to connect my annexe to services?

No. We include a standard 10m service run for all annexes within the price.

Are all electrics and heating included within the price?

Yes. Gas central heating or digital electric radiators are fitted as standard.
We also install all electric sockets, switches and LED downlights throughout.

How long will my annexe last?

There’s no reason why one of our annexes won’t last at least 70-years.

What cladding do you use on the outside?

Marley Cedral Lap weatherboard is our standard finish, which is available in over 20 colours, or green untreated oak for a more natural finish (a popular choice in conservation areas).

Don’t flat roofs leak?

Not at all. EPDM synthetic roofs have significantly advanced over the past few years, and all our flat roofs come with a 50-year manufacturers warranty.

Can you build a pitched roof?

We certainly can. For a small upgrade, each of our annexes can be finished with a warm pitched roof, available with a choice of roof tile. Ceilings are vaulted in main living/dining areas to create an additional sense of space.

What are your annexes built on?

We typically use Swift Plinths, the Swift Plinth system is extremely strong and can take.