How much extra do you think a granny flat would add to a property?

[user746016]

We already have the building there but thinking of converting it. It's currently a brick stable block with power and water. It would become a small detached granny flat with a living room/kitchenette (3m x 5m), a separate bedroom (3m x 4m) and a shower room.

I'm just toying with the idea at the moment. Googling just tells me 20-30% but that doesn't seem even vaguely realistic (Detached house worth c800k in the Midlands).

Hi, before you proceed, just work out the council tax. In some circumstances, you have to pay council tax on it, and depending on who is living in it, they may or may not be exempt. I think annex properties are a bit more complicated now.

I don’t know about the added value but do look into how two kitchens affects the status of a property. Two kitchens can put people off as there are anxieties about council tax liabilities. Also insurance and mortgage companies can be nervous about them.

I think it opens it up to a different market.
It would put us off a house.
Friends snapped up a house (as in put theirs on the market to get it) a house with an annex, as they can see in 5 years her Mum is likely to be living with them.

I wouldn't do it for the sake of it, but if it's something you would make use of, go for it.

We have older teens and aging parents so it would probably get used and in the meantime I would use it as an office.

Yes a self contained granny annex will have its own council tax. But that wouldn't put me off.
Suss out how much to do the work first. You'll probably get that back. But also ask a local estate agent how much value it might add.

About £30k to do the work.

I agree with the person who said it just changes the market rather than being a straightforward "this adds value". It's not the kind of feature people are indifferent towards, it's one people will either really, really want or consider a total turn off. So it narrows your pool of potential buyers, but I imagine the buyers that remain will pay over the odds for it.

I'd say to work out the value, you need to only compare to other properties in your area with annexes. It's not "here's the value of an equivalent 'normal' house, now add on £x for the annexe", it's "how much for a house with a granny annexe".

Do you need a granny flat? If you are in need then do it. If it's a longterm family home then you do what you need to make it work for you.

As more young people are unable to get a place if their own what used to be a granny annex can be an adult child annex for a few years before Granny needs it. I think they are more popular than they used to be.

Or as an airBandB if you can get the right sort of tenant. My old neighbours have a salesman living in their annex Mon-Fri each week.

If it can easily be added into the main house I think they are more valuable than those which couldn't flow as part of the larger property.

In my area they are hugely sought after as granny/adult child flats, or spacious home offices. It's difficult to get the 'change of use' planning for them but your council could be different.

These are popular with people operating businesses from home eg dog grooming, nail parlour. These need planning permission though.

I believe that if it connects to the main house and doesn’t have a kitchen then it is just an extension.This was my situation with my mother’s annex when she went in a care home.I was told to not pay council tax I needed to remove the kitchen even the pipe work.We left it as it was and rented it as a holiday let.

It’s a separate building about 6m away from the house at the back.

Take the point that it might put some people off.

It wouldn't be the sort of thing I would do to add value, more because I needed it. Adding value to the house might be a (far) secondary consideration.

Have you thought about designing it in such a way that it could easily be considered an extension or changed into one ? That way it is either an extension or granny flat - a lot more flexible and open to more buyers.

@user746016 I have a similar situation, very large stable+bath house detached from the house. Bearing in mind what I have read about the kitchen and council tax I was considering designing it with a free-standing kitchen and electric cooker that can all be removed if needed. That way it could be marketed in the future as a games/hobby room not an annexe. I think any change of use to living accommodation needs change of use - but it is only eligible for council tax if it could be lived in self-sufficiently and separately from the main house.

It is definitely something we are considering for the same reasons you give.

As others have suggested you need to look into the council tax implications.

A granny annexe has huge appeal to those that want/need one and absolutely none to those that don't!

A separate teenage den / office space / home gym can have wider appeal.