Paying the mortgage or other household expenditure does not entitle you to a greater share of the equity.
You may, however, be entitled to compensation for the money you have spent by way of "equitable accounting". This allows the Court to make adjustments to the money received by each party, even where shares are fixed.
Included in equitable accounting can be payments towards the mortgage or, in some cases, improvements to the property or an obligation on one party in occupation to pay occupation rent to the other party post-separation.
If you have excluded your ex-partner from the property, then he may be entitled to ask you to pay rent for occupying the property and may insist on conditions for your continued occupation of the property.