Can I sue for half of his share?

Ontario's Family Law Act sets out the regime for property division between spouses upon the breakdown of a marriage known as equalization. Parties are required to exchange financial disclosure in order to calculate each party's "net family property" (NFP). NFP is the value of each party's property on the date of separation, taking into account all assets and liabilities, and excluding property held by each party on the date of marriage, subject to certain exceptions. Once the NFP's of both parties have been determined, ​in most cases, t​he spouse with the greater NFP will owe the other spouse an "equalization payment" of one half the difference between the two NFPs. In your specific situation, if your husband purchased the new home prior to your date of separation, it is an asset that will be​ likely be​ taken into account in determining his NFP and may affect the amount of any equalization payment.​ You should see a lawyer to discuss the particulars. There are factors such as length of marriage, exclusion of certain inheritances and gifts, which could impact whether certain property is subject to be divided and how.​