As a starting point, he would be entitled to his 'beneficial interest' in the house. (e.g. if you both owned 50% each and no mortgage he would be entitled to 50% as would you)
BUT (big but!!!) you NEED to get a good divorce lawyer, because you need to get the situation moved on from the his/yours beneficial interest scenario, which may see you having a large charge or being forced to sell.....
You need to strongly argue that your children deserve a place to live, there are so many things to consider which will shape the final outcome of the settlement. Everything is negotiable. It is so fluid.
Last divorce lawyer i spoke to (very recently) told me that the judge doesnt like to see one party come out of a long term marriage with nothing.
(from my POV that really pissed me off since my abusive H has used and abused me and the kids for years, especially financially, so as far as im concerned hes sucked the marriage dry financially for years, hes already had far more than his fair share of 'maritial assets'..FFS).
ONE very important point: remember that everything that has been bought since the marriage began, even if it was bought by one partner alone or even gifts received by just one of the couple...all of these are potentially up for grabs in the split. So if he has any valuable things he thinks of as his own, (car: for instance) you might be able to 'trade' your half share of them them against his share of the equity in the house, to get it smaller. Divorce lawyer told me to photograph everything. Photograph all 'his' valuable stuff, because its half yours.
If hes thinking of forcing a sale and therefor making you and DCs possibly homeless or in a precarious housing position, Thats just not a nice way for him to treat his DCs....fight back