To not pay off DP's debt?

Absolutely not.
This man is always going to have debt.
Is he taking on an extra job?
Nope?
Just hoping you are foolish enough to step in.
Save your money for your children who need one parent who isn't a loser with money.

Maybe offer him an interest free loan and get paperwork drawn up with a repayment schedule so you are just putting off your renovation by a year or so. Does he pay towards your mortgage or does he just pay bills?

How much of the debt is directly attributable to your maternity leave? Pay half of that.

Have you full oversight of all his finances?

So he's in debt because you had another baby and were on maternity leave.

You both should have considered if you could afford another child at that time really.

If you are buying a house together, and you aren't married, please make sure you are protecting the equity/deposit money you are bringing into the purchase. Especially as your relationship is on Rocky ground.

No reasonable partner would object to you protecting yourself. Is he putting any pressure on you to help with his debt?

Get the slate clean then and then have a sit down every month to review finances to make sure things can't get off track again.

The financial grief may drag you all down. However, credit to you both for deciding to face up to it and deal with it. But please for all your sakes have a red line re. more debt.

Well if this was reversed the man would be told he has to help the woman out

You want to stay with him financially no idea why so you will keep on getting this forever he won't change

Honestly? Speaking from experience? I wouldn't ever saddle myself with someone else's debt. Especially if we weren't married. Been stung before.

If he's on £45k and spending over half his take home on clearing the debt, it should be gone in 18 months no? So he grits his teeth and gets on with it. And if you want to give your relationship a chance, you grit your teeth and accept that for the next 18 months you're paying for most of the kid and household expenses.

If he manages to clear the debt in 18 months then going forwards he can contribute what he should to the household. But make sure the house remains in your name only, for the sake of your DCs.

Hard no to paying off his debt.

could at least partly have been to try to support our family,

I think you should give a bit more detail. If it could, partly have been supporting the family, what was the rest for?

Given he's done it before I don't think paying off his debts will benefit them as a family at all because he'll just do it again!!
If the relationship were in a better place I'd perhaps think differently but in the current circs, not a chance.

He needs to grow up to be honest, though being honest I also think you should walk away from him and leave him to sort his own problems too seeing as no amount of helping him seems to help.

Over how long a period has he built up this debt, and for how long have you known about it? Before paying anything like that off, I would be wanting a complete breakdown of everything the money was actually spent on.
I'd also be wanting to know how come he has been able to get into so much debt again when he has an IVA against him.
You can't get into debt unless lenders allow you to have loans, credit cards or an overdraft. So how come they let him borrow so much with his poor credit history?

No way. I think if it was the first time and there was a very clear reason for it then I might consider it. But no... I don't think you can trust him not to do the same again. I think he needs to make a clear budget plan, stick to it and pay it off his own income. I'd get an independent charity like CAP or debt action to work with him. A quick fix isn't necessarily the solution you think it is if he has a pattern of running up significant debt. You'll kick yourself if you do this and then he's done the same again and you still can't do the work to the house. He needs to set a clear budget plan for himself and stick to it. If he's struggling with another underlying cause like gambling or mental health then he needs to address that.

You mention he's run up debt to cover things while you were on maternity but it sounds like you weren't aware of this happening? Was it all absolutely essential spends? If there were unavoidable things you needed as a family that you agreed on then yes I'd give something towards it, but i would only cover essential family spends. It sounds like you need to stay communicating much better over money - 20k is a very significant debt to work up without one partner being aware of it. For me I'd tell him I need absolute transparency with money from now on and all credit spends should be agreed as a couple. Anything less than this tbh would be a deal breaker.

If you're going to stay with this man then you'd be a better-off family if you were debt-free.

Are you going to stay with him?

You've obviously never had a partner who runs up debt with apparently no clue how it happened.

Nope. It's mytserious how your identical income to his goes so much further, is it not?

I have to say that I think I'd pay it.

He's drowning in debt - half his monthly income is going on debt. There is no way he's going to get straight without help. And you need him to get straight in order that he can function as an adult, rather than an idiot who is burning and mismanaging money.

Unless he has parents who might be able to contribute something towards the debt repayment, I would pay it. I couldn't contemplate house renovations if he was in debt.

You are supposed to be a team working towards a common goal - family/kids. If you own the house and he's just servicing debt, essentially he will be a long term cocklodger whilst you do the adulting. If you clear the debt, he at least has a chance to grow up and function. Especially if some of the debt was acquired during mat leave when the family were short of money.

I don't know. Either you are a family or you aren't. I'd want to be a family and try to work as a team and unfortunately that involves paying this off.

Honestly this is just so unfair. Surely if he's run up debt supporting you on maternity leave, then it's not his debt alone is it? It's family debt.
You need to sit down and go through it properly and use your equity to pay off any that could be considered as family debt so he's not disadvantaged.