Sharing The Cost Of Living In A Granny Annexe

Many people realise that living in multigenerational households can be a cost effective way of providing care and support to each other. But how do you make sure you are sharing the cost of living in a granny annexe, and what are the additional costs?

Multigenerational Living On The Rise

These days more and more households contain more than 1 family. Indeed, the Office of National Statistics issued a report on the 15th November 2019 that stated it is the fastest growing type of household in the UK, albeit still the smallest.

The Guardian estimates there are about 1.8 million multigenerational households in the UK.

Motivators seem to be reducing isolation and rising living and housing costs.

So in this blog we are going to look at how you can share the cost of living in a granny annexe, and what those costs might be.

Will My Household Bills Rise With A Granny Annexe?

Naturally, a granny annexe is going to increase the overall costs of a household, especially in terms of food and energy consumption.

Because a granny annexe is an ancillary building the utilities are run from the main home.

This naturally means there will be an increase in energy costs from the primary house.

Each iHUS granny annexe has its own kitchen, which means the collective household will have two washing machines, two ovens, and two places consuming water.

There are also two spaces to heat, the main home and the granny annexe, so overall the costs will be higher for heating bills.

granny annexe kitchen


How Can A Granny Annexe Save Me Money?

But don’t panic. A granny annexe is extremely energy efficient, so the energy consumption won’t be that much higher.

Properly insulated and glazed, they are quick to heat and stay warm, even on chilly days.

Electric storage heaters installed as standard, mean you only need to heat the space you are in, so you aren’t paying to heat empty space.

Or, you can choose to upgrade to digital radiators, that you can control via an app. This allows you to save even more money by remotely turning on or off your radiators, depending on where you are.

You can also choose underfloor heating, which makes the most of convection heating, rather than heating a room from halfway up.

LED lights are installed as standard throughout, saving you even more money, as they are famous for their efficiency.

What Costs Can We Share Living In A Granny Annexe?

Many families do decide that sharing the bills through living in a granny annexe is the cheapest way for them to live.

Although the utilities are fed off the main property, we can install a separate counter that allows you to fairly proportion the electricity and water bills. That way, one ‘family unit’ isn’t paying more or less than their fair share.

There is also only one council tax bill to pay.

Many people over the age of 75 really struggle to get a mortgage but living in a granny annexe removes that complication.

You might find that sharing food bills is perfect for your family. You won’t need to have ingredients go out if date anymore, as you can easily share between you all.

Internet, streaming services, and subscriptions usually offer a family deal so you can have multiple accounts on one address and spread the cost between yourselves.


image of generations for ihus blog on sharing the cost of living in a granny annexe

Our Top Tips For Sharing The Cost of Living In A Granny Annexe

  • The owners of the main house should be realistic and well informed about exactly how much it costs to run their home before the granny annexe is built.
  • Proportion approximately a 30% increase in that baseline and monitor regularly.
  • Have a frank conversation before you agree to go ahead with living in a granny annexe to decide how the bills will be apportioned.
  • Consider a joint account for things like food and gardening items so one person doesn’t end up paying for everything all the time and another owing. Or worse, having to keep track of who owes what to whom.

Get In Touch

Here at iHUS, we have been building granny annexes for happy families for over a decade.

We have seen plenty of people happily learn to share the cost of living in a granny annexe without issue so we can pass on their expertise. Or, have a look at our iHUS Community and hear it from the horse’s mouth.

We also understand that sharing the cost is a big deal to people, rightly so, which is why our service is tailored to make it easy to share the cost.

If you would like to chat with us, get in touch on 0808 164 1111 or email enquiries@ihusprojects.com. We will be happy to discuss options with you.


View Our Annexes

The Cantley is the smallest annexe in our Core range and is one of our most popular models for independent living. The floorplan is designed to maximise space and fits comfortably into most back gardens.
As one of our most popular one-bedroom annexes, the Bawtry is the perfect choice for elderly care or an independent young adult looking for their first home.
The Ravenscroft is a spacious one-bedroom annexe, designed for those with a larger garden plot. All three footprints utilise a central shower room to separate the bedroom and the open-plan kitchen/living area to maximise living space.

Recent Projects



This idyllic annexe is home to Theresa and Austin situated at the bottom of their daughter and son in law’s garden. Having always lived very closely to one another, the family were convinced this way of life wasn’t going to end anytime soon, & their wonderful annexe has made this a reality!
Speedwell Annexe


Our customer moved into her Annexe in January and is thoroughly enjoying her lovely new home. She describes her Annexe as ‘Warm Sunny Cosy & Comfortable’. Click below to watch an exclusive interview with the owner and watch their Annexe walk through!
Williamson bespoke granny annexe

Jenny Williamson

The Williamsons family moved into their Annexe over 3 years ago. When visiting the family they told us life in their new home exceeded their expectations for many reasons. So much so, they wanted another iHus building! Click view to find out more about their story and take a look around their Annexe.

Wendy Hamm

In Autumn 2020 Wendy Hamm and her family approached iHus as they were contemplating an annexe build in their back garden to house Wendy’s mother. Wendy’s mother Jane, 82, was living over an hours drive away from the family. Wendy’s day to day responsibilities meant that visits to Jane were a lot less frequent then they would have wished. Read their story here.

Download Your Free Annexe Brochure

Simply fill in the form and you will be emailed a link to download our 32 page annexe brochure.

    Simply fill in the form and you will be emailed a link to download our 32 page annexe brochure. Please check your Junk mail if your brochure doesn’t appear in your inbox

    Request A Hard Copy?:

    Download Your Free Annexe Brochure

      Simply fill in the form and you will be emailed a link to download our 32 page annexe brochure. Please check your Junk mail if your brochure doesn’t appear in your inbox

      Request A Hard Copy?:

      Talk to a Consultant

      We know that building an annexe can seem daunting which is why we created our Signature Move process.

      It all starts with a conversation where we want to get to know you better, understand what you need and give you an opportunity to ask any questions you might have.

      To get started complete the form and a member of our team will get in touch to book you an appointment with a consultant…