Cost of splitting detached house into two spaces

gkcf22

Hello all,

Just seeking some input on this from anyone who's done a renovation/something similar in Dublin.

My partner's father lives alone in the old family home which is a large detached residence (4 bedrooms upstairs, 1 bedroom downstairs to the side) with an ample garden side space. He has recently had some health issues and is no longer able to drive and this has brought us to the idea that we could potentially sell up our own property (we've only lived here around two years) and renovate the house/extend it to basically facilitate two separate residences. I've seen other large houses have this done and I figure it'd be affordable between our own sale/my father in law's input (if this is something he actually wants himself of course). The house is an BER E2 property and in need of some general redecorating/retrofitting. Before his illness he had new windows on order and these are probably going to be going in regardless of what happens in the coming months but if we decide to move ahead with the plan then we can delay this to some extent. We were also planning to get the whole house wrapped (external insulation) before this happened. So these were things that would have been done to the property regardless.

Has anyone here split a property in this way and would they have any roundabout cost ideas? In my head (not an architect by any means) I figure we could take the side of the house and do a small extension to the rear and take in half the house to create one home, while the other side of the house would create the other. Apologies if that doesn't make sense! Internally I think new bathrooms and kitchens will be a must as well as some replastering of the ceilings, I've no idea how much that costs but I know kitchens can go wild. I've seen lots of houses in the area being bought up, ripped out and fully renovated so I figure this would cost something similar but I just want to make sure it's a feasible option before going into it. Thanks so much for you time and input.

DOCARCH

I assume you are talking about splitting one house into two separate houses (rather than one house and a large 'granny flat)?

If you are talking about splitting into two separate houses, it's not for the faint hearted!

You need to get planning permission for the split/for two houses, with each house complying with relevant/current development plan standards for overall size, garden size, off street parking, etc.

And then when it comes to building, each house must comply with current building regulations for new houses (energy performance, sound, disability access, etc.), For one of the new houses, new drainage and service connections (electricity, water supply, etc.) will be required.

gkcf22

Hi Docarch,

Tha ms for that, yes I suppose not a granny flat as such, but I suppose that could be an option as well, it's more so to create a space where we as a couple can live separately but also still be in proximity to help out more easily, and so my father in law isn't as isolated (he is widowed in recent years).

Ether way I think it won't be a project for the faint of heart but hoping that there is a feasible option! I suspect to do it the way you've set out would be significantly more expensive than a granny flat type option, if we just did a self-contained unit within the house I'm guessing we could avoid those costs?

downtheroad

This is a bit of a tangent but if you sell your home, move in with your father in law and don't have an interest in another property you can avoid capital acquisition tax on inheriting the house. Not sure if this would apply if you split the house in 2 though.

https://www.revenue.ie/en/gains-gifts-and-inheritance/cat-exemptions/exemption-for-dwelling-house/qualifying-conditions-inheritance-on-after-25-december-2016.aspx

DOCARCH

Doing a granny flat would definitely be the cheaper option, as any addition to the existing house would be an extension to the existing house (rather than two new houses and all the red tape that brings) and refurbishment of the existing house would be more straightforward too.

The only requirement for a granny flat is it has an internal direct connection (i.e. door) to the main house. The granny flat itself can be as big as required/as big as space allows. I have seen in the past granny flats with separate living room, separate dining/kitchen and with two bedrooms both ensuite. It does not have to be as dingy as the term granny flat sounds!

From a planning point of view, it would normally be conditioned the flat be used by a family member and when that use expires, that the flat be used as part of the main house.

gkcf22

Yeah that sounds like the way to go then, there is a front porch which could definitely provide for a sort of separate entrance type of thing without making it separate (if that makes sense).

The intention would definitely be to keep the space as part of the main house in the long run it's just to make it work as two independent spaces to be honest! We are planning on getting am architect to take a look and see what design could work, if anyone has any recommendations please feel to pm me! Again thanks for the advice.

Gael23

The easiest way would be to construct an extension and build a granny flat sort of thing.

As for the financial side usually how families do it is they would be set to inherit the house but you and your partner would fund the renovation. It’s still substantially to your benefit

gkcf22

@Gael23 This is it, definitely would be. I just don't know how it would work with other sibling re inheritance yet but I think that will have to be sorted too. I don't know if anyone would have ballpark figures for something like that that they've done (Grammy flat extension type thing and a bit of redecorating/renovation)? I know completely impossible to say in current times but would be good to get an idea of what others have done.

Gael23

https://www.boards.ie/discussion/comment/118885571#Comment_118885571

That’s a conversation you all need to have regarding inheritance. Perhaps if there is other assets or cash that would go to the rest of the family. The cost depends on so many factors but it’s not going to be cheap like 5 or 10k. One of these I’ve seen was an en-suite bedroom and it’s kitchen/living area combined linked to the main house by a door. So then on the eventual death of the older person it was easy to combine into the main house

gkcf22

@Gael23 yes I saw a few exactly like that when I was researching, it's exactly what we would be hoping to do and certainly wouldn't expect it to cost 10k 😂

BryanF

https://www.boards.ie/discussion/comment/118895814#Comment_118895814

How much were you expecting?

ax530

Knew people who did this. I'm not sure on costs my only input is they didn't officially make two houses as such shared enterance hall but had two kitchen living room ECT. However can go from one side of house to other once inside. From outside still looks like one house. The other family opposite started with two semi Ds joined however built internal doors so separate houses joined

Imagine plumbing ECT could be expensive if most pipes currently on one side but want new bathroom s or kitchen on separate sides.

From watching Bannon ECT on TV can see that there is no limit to what you could spend however clever design would go a long way in this type project so worth talking to an architect

Shau_98

Just wondering if you managed to get this priced?

AndrewJRenko

Might be worth getting in touch with these folks

https://www.avahousing.ie/