Would it BU of us to write our Will this way?

I think you and your partner are lovely people considering everyone's needs. I have a large family and one of my siblings struggles much more than the rest of us, all of us always try to help her. In your position, I would leave 50% to my DB and share the remaining to your nieces and nephews. I think leaving him to live his days out has problems. They also have an inheritance coming from their parents, I would assume, so I think this is fair. You see what people are really like when money is involved.

This.

Slightly different situation but my Mum left her house to me and my brother with the proviso that her partner can live there for as long as he wants - we can't sell it without his written permission. His daughter has his POA and is determined not to make things easy for us.
I don't really care about the money, my Mum had an illness that meant I assumed anything she had would be needed for care so I was expecting nothing at all BUT its a very difficult situation for the following reasons
Me and DBro have no closure, all my Mums things are there and he has completely neglected the garden that meant so much to her. I don't visit as its too hard (appreciate this probably won't be an issue as you don't have DC)
He has dementia and there are carers going regularly but he would actually be better in a home (my Mum actually said that to me before she died) but because he has somewhere to live he can't access the help he needs. In the 6 months before she died they had started discussing moving to sheltered housing or similar and they were getting to that point of needing it I think
The house is starting to deteriorate and getting him to maintain it (a condition of the will) is difficult as we have to deal with his daughter who sees no reason to
Its a struggle to get him to pay any costs associated with the house such as management charges, again this is a condition of the will.
With hindsight my Mum should have really put a time limit on it but we always assumed he would die first as he is older than she was with a couple of health conditions. IF she had done this then he could have done a slow transition into somewhere where he is more supported with regular company and proper care instead of stubbornly living in a house where he is mostly alone surrounded by reminders of my Mum and carers calling in for 15 minutes at a time that will increasingly not meet his needs - its too big and he is starting to struggle with stairs.
Before anyone criticises me for not doing more I don't like him and tolerated him for my Mum and he has 2 daughters and 4 nephews who can help him if they choose to.

They have no right to your money. It might feel different if they were your children but they're not so tough luck if they don't like it. They should be grateful for anything they get!

No kids and just changed our wills leaving everything to each other and then split evenly between 10 reputable charities. None of our relatives needs our money. We've been very good to them in the past but it's all been taken for granted and the favours continue to go one way. Decided none of our lot deserve to inherit from us and we're happy that our money will benefit people who really do need some help.

This is the best advice I’ve seen so far.

Get everything liquidated & leave him a share. He can then use it for a deposit for a better rental or whatever his need is at the time.

If he lives rent free who is going to maintain the place? It could cause a lot of stress for your extended family/inheritors at the time the roof starts leaking, the boiler fails, the windows fall apart. Who will sort and pay for that?

Would I lt be easier to leave an amount to him and then split rest between dns? So he could use it as he chooses.

Or split it between him and dns.

By giving him a free rental he is restricted to where he lives. It may not be suitable for work/ relationship. In which case the house is sold and he gets nothing.

Family may also pressure him to sell/ fall out with him.

This has disaster written all over it! Just leave the house to him and let him decide where it goes in his will. Fuck the grabby ones who expect things, that's not on.

"This would of course mean that they’d have to wait for their money, which we know that they’re expecting because of comments made over the years (although we’ve never said what our plans are)"

That is very predatory of them. I would not want to leave as much as a brass farthing to such people.

I think I'd start casually mentioning what my plans were. The plans I'd voice would be totally fictitious, involving donkey rescues, medical research, clean water - whatever charity request next comes through the post/on daytime TV. Let them get shirty at that, but I'd definitely introduce them all to the idea that they will be getting nothing.

I'd then draw up my will to have that brother as my sole beneficiary.

I would be thrilled if this was me. I’d AirBnB it straightaway, and live in SE Asia for the rest of my life.
Or turn it into a crack den. Not sure which.

I’d definitely leave everything to charity if that’s what you really want. Don’t tell your family, the resentment won’t matter if they don’t know in advance because you’ll be dead when they find out.

Please don't leave anything to the grabby folk. Look after your brother.

My childless great uncle has written his will so that his estate is split evenly between his living nephews and his great nieces and nephews. That seems fairest.

A properly written immediate post death interest trust will provide for him to live there for his life, or to downsize, at which point any capital freed up can be distributed amongst the other beneficiaries, or held on trust with him entitled to its income (ie interest)

It needs to be done properly, and will then work fine, but only a solicitor can really draw up such a thing correctly.

As you get older you may need some support to live at home. One of your nieces/ nephews may step up to help you both from kindness not grabbing. You may want to leave it all to them. Also if you die first an inheritance from your unrelated dh may incur serious inheritance tax for your dB or even the others. It would in lreland anyway.
This may be a mad thought but could you sell your home now and buy 2 apartments. A small one that your DB lives in for his life and a bigger one for you both that can be distributed immediately after death.
A lot to think about.

@WillOrNot sorry I didn't get to edit my post in time. I wouldn't have suggested it if I'd realised it wasn't possible.

Is it possible for you to give your brother any help now while you are all alive, well and relatively young?

I'm not sure what help would be useful, maybe a pension review for him and looking at what plans he has for his old age. Or seeing it is possible to give him smaller amounts of money now to pass onto his children if it would be of use to them. There might be a small thing you can do now which will be of more help than possible help in the future if his younger sister predeceased him.

Cross posted - just seen you have mentioned potentially using equity release so my suggestion is likely not possible.

Not with a barge poll. The money will be spent on fees.
OP, I’d just leave him the house.
Your estate would get to the nephews nieces eventually and they deserve to wait for mentioning it to you. Greedy fuckers.

My friend has never married or had children and lives alone. Her sister is fine and her adult nephew has certainly made it known he expects to inherit everything of hers. She is asset rich and cash poor as has a small pension and has never ever lived with anyone so everything has been on her. She is thinking of doing equity release because she doesn’t care how much she leaves now because of his grabby attitude.

When your dead resentment is irrelevant.

What you need to do is think about what makes you happy and what you actually want. Put aside what any other person has said or intimated over the years and concentrate on what you both want.

You haven’t said what stage of life you are at either.