A more thorough explanation:

Ameliorative waste

Ameliorative waste is when a tenant makes changes to a property that increase its value without getting permission from the landowner or future interest holder. This is different from permissive waste and voluntary waste, which both decrease the value of the property. In the past, the property owner could recover the costs of undoing the changes, but in the modern-day United States, they can only recover damages if the value of the property decreased.

If a tenant on a farm with a life estate destroys an old barn to plant more crops, this would be considered ameliorative waste. Even though the barn was destroyed without permission, the overall value of the farm increased because of the additional crops that could be grown. Therefore, the remainder owner cannot sue for damages in the United States.

Another example of ameliorative waste could be a tenant installing a new heating system in a rental property without getting permission from the landlord. If the new system increases the value of the property, the landlord cannot sue for damages.

These examples illustrate how ameliorative waste is different from other forms of waste because it does not decrease the value of the property. Instead, it increases the value, even if the changes were made without permission.