It means that your husband is entitled to 26% of the equity of the property, with you entitled to the rest.
The Mesher Order means that he is not entitled to the money, and you are allowed to live in the property until any of these occur:
The youngest child reaches 18;
You remarry;
You die
As soon as one of the above occurs your ex will become entitled to his share in the property. Of course, you could give him the money and stay in the property, perhaps by raising a mortgage, when any of these events occur.
It is designed to ensure you and the children have security in living in the family home, whilst protecting his legal entitlement.