Anyone built a Granny Annexe?!

[GuruK]

Hello, I’m wondering if anyone can offer me some advice. In the next year or so I’m hoping to purchase a house that we can modify to create an annexe to accommodate my mum. Depending on the property (likely a semi-detached house) we would either like to build a lodge type dwelling at the bottom of the garden, or if the garden is not large enough, a 2 storey extension on the side of the house. Has anyone done anything similar? Can you tell me what sort of restrictions we’d need to be aware of or what permissions would need to be obtained? Any other pitfalls to be aware of?

Thanks in advance!

Stuff to think about: council tax, utilities etc - you will need to fulfil whatever conditions your council has for it to count as one dwelling for council tax purposes. For example it might need to have an internal door joining the 2 areas and there might be rules about having a separate front door. Also it may not add much value as you might think. Expect it to add less value than it costs, possibly by quite some margin.

You'd have to have its own water and gas supply. I work for a water company and depending on how far into the footpath and pavement they need to dig it could be anything form £1000 upwards.

If it needs a road closure for connection you could be looking at £2500 just for traffic management.

Does she need to live completely separately? I believe there are different rules depending on whether there is a full separate kitchen or not. If she can make do with a living room, bedroom and en suite, maybe with a little tea and coffee station and wee fridge, and share your kitchen, it may be simpler. Also should your situation change or (in the very far future hopefully) she pass away it can be a guest room or something.

Re: planning the easiest would be to go for houses with precedent set for extension. When a house comes up go onto your local planning portal and see what’s been approved. You can also have a preliminary consultation with a planning expert between making your offer and exchange to give you more confidence.

You may get stung on the council tax thing anyway - there isn’t much rhyme or reason in what councils bill as a second dwelling. In practice, it seems pretty random. So although the council may have rules you can try and follow to avoid a second council tax bill, be prepared for them to send you a bill anyway.

I grew up in a set up like this - Granny flat on side of our house. It was lovely as we saw a lot of Granny growing up, but pitfalls - once she'd died we then had a separate property to pay for, including council tax. We did let it out to students for a while but it was v annoying as they were in very close proximity (shared garden, washing machine etc). It then took AGES to sell once my parents wanted to downsize - at least 18 months on the market because there's a limited number of people who want a property like that.
Who will own the actual building? Ours was complicated as my parents owned the land, but my Gran's money was used to build the flat, which she then left to me and DB, except it couldn't be sold as the land was separate.

Also, what happens when the relative becomes very infirm? Eg can't manage stairs?

Who would be funding it? If the money would be coming from your mum, then if she later needed expensive care - and there wasn't enough money left to pay for it - the council could take the view that it was deprivation of assets and come down hard.

We're hoping to add a guest annexe when we build our extension but thinking about how to make it suitable for wheelchair user as my DH has a progressive illness and may need one later. Looking at wider doors, shower access etc and I expect these are considerations for you too. Also easy use taps and storage possibilities.

Where I live you’d be unlikely to get planning permission for a detached annexe. One attached to and integral to the family house might get pp. no separate access or front door and no separate staircase (as these would make it potentially severable).

I have seen several houses that have converted an attached garage to a bedsit. Would that be a consideration?

Hello All, I can only apologise for this very late reply and thank you all so much for your tips and suggestions. There is a lot I hadn't thought about here, particularly regarding issues with full separate kitchen or additional staircase. On reflection I think probably a two storey extension on the side of the house would probably be the better option rather than a garden dwelling. At the moment mobility isn't an issue but obviously something to consider for the future.

@GETTINGLIKEMYMOTHER yes it would be my mother funding the extension so that is certainly a concern, though I would aim to pay for my mothers care of do it myself if I can't afford it!

@PooWillyBumBum I think for the sanity of everyone involved, including my mum (we have two young kids!), an entirely separate living space would be necessary. Would be more than happy to put internal doorways in but she'd definitely need her own kitchen. That's really helpful regarding planning thank you.

@longearedbat yes I think thats probably going to be our best option actually, thank you.

It sounds a bit complicated to me to have a 2 storey extension with a full kitchen. Will it need its own staircase as well, won’t that need to be large enough to accommodate a stairlift one day. Otherwise they will need to be in and out of the main home anyway to go upstairs?

I had a few friends who had grannies who lived in annexes, but they were always - living room, bedroom and bathroom only - usually accessed by main family kitchen (I have seen a few for sale like this).

MIL nearly bought a house right next door to BIL. It was a one bedroomed house and BIL has 4 bed house. She didn’t in the end because of the stairs as eventually they would be an issue. They were going to knock down the garden wall to have access between them.

@GuruK just be aware of the cost of care if you end up paying for it yourself (as the value of her house has gone into yours). Could you fund £800-£1000 a week indefinitely? Or would you have to sell up to release the money?

I was thinking there is a house near me which had a large patch of garden to the side. This has been separated and they have built a small bungalow on there. It seems to have taken quite a while but it’s a nice separate dwelling and bungalows are in short supply here so probably worth a bit too.

Best wishes with whatever you decide, OP, but please be aware that if, God forbid, dementia should strike your mum, it can be unbelievably exhausting and stressful to care for. And the care needed, if and when you can no,longer cope, is very expensive.
( I say this as someone with 2 worn out T shirts, from my mother and my FiL, both now RIP. )
My mother was in a dementia care home for very nearly 8 years, and she was 89 when she went in, having already had it for several years. I should add that she was not typical, though.

We did this but instead of a separate dwelling it’s an apartment within the house. Much easier for tax purposes and we rent it out quite frequently when it’s not in use by parents as the entrance is quite far from our living space.

Thanks so much, lots of considerations to take into account here. Based on this advice I think we would aim for my mums annexe to be just on the ground floor with her kitchen being listed as a utility room just off our kitchen. This future proofs us for when she is less mobile too.
I should say that she is only 64 at the moment so the need for care and or being in a home is hopefully a fair way into the future. Our reason for this plan is that she has been on her own for 30 years and suffers with ME. She currently lives a 40 mins drive from me and there is not really a way to reduce that as she's in a Park home so wouldn't have enough from the sale of that to buy even a 1 bed flat close to me. Living with us would enable her to see me and her grandchildren more regularly but for shorter intervals which would be much more manageable with her condition and would hopefully improve her general wellbeing as she'd have more social interaction.

Your responses have really helped me narrow down the sort of extension we'd need to build and therefore the style of house we need to find. Thank you!