Thank you for you response and for clarifying that for me.
If you are joint tenants in relation to the property then the legal position for the division of equity in the property is equal.
That being said, as you have continued to pay for the property since your separation and your ex has not, then if agreement cannot be reached between you then you can ask a court to make a declaration as to your interest in the property to consider the additional monies that you have paid.
What you need to know is that any joint owner can make an application to court for an order that the property be sold so that there interest in the property can be realised.
If your ex did take such action then there is no guarantee that the court would agree that an order for sale in relation to the property be made. I say this because the court does have to give consideration to any minor children residing in the property. There does not appear to be sufficient equity for the house to be sold and the equity realised and for the children to be rehoused so it is not likely that a court will agree that the house be sold whilst the children are minors.
You need to consider family mediation. They are independent and will try and help you reach agreement as to the shares in the property that you both should get and when the property should be sold so that your ex's share can be realised. Google family mediation in your area and give them a call to self refer.
You also need to consider severing your joint tenancy. This is because as joint tenants the right of survivorship applies. This basically means that should either of you pass away then the whole property would then pass to the remaining joint tenant. If you are separated you may not want your share to go to him. see this link for how to sever the joint tenancy:
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