Loss of use is for the downtime of the vehicle. When the rental vehicle is damaged the rental agency can not use the vehicle, and the rental agency has a right to be compensated for the loss of use of their property.
Loss of use is a property right to which any owner of property is entitled. It is based on the principle that an owner of property has the right to use that property in whatever lawful manner that they choose. When an owner of property suffers damage for which another party is responsible, the owner is entitled to be compensated fully for the injury. Compensation for a harm to property includes the amount of damages to property and loss of use.
Section 928 of the Restatement (Second) of Torts provides that damage for harm to chattels includes damages for the loss of the use of the chattel. Section 931 discusses loss of use damages. Comment (b) provides that "[t]he owner of the subject matter is entitled to recover as damages for the loss of the value of the use, at least the rental value of the chattel or land during the period of deprivation. This is true even though the owner in fact has suffered no harm through the deprivation, as when he was not using the subject matter at the time or had a substitute that the used without additional expense to him."
