If the defendant intends to claim allowance for improvements made upon the premises by himself or those under whom he claims, he shall file with his pleading a statement of his claim therefor, in case judgment be rendered for the plaintiff.
Va. Code Ann. § 8.01-160, under Chapter 3. Actions..
Va. Code Ann. § 8.01-160
If the defendant intends to claim allowance for improvements made upon the premises by himself or those under whom he claims, he shall file with his pleading a statement of his claim therefor, in case judgment be rendered for the plaintiff.