Fire insurance is a contract to indemnify the insured for destruction of or damage to property or goods, caused by fire, during a specified period. The contract specifies the maximum amount, agreed to by the parties at the time of the contract, which the insured can claim in case of loss. This amount is not, however, the measure of the loss. The loss can be ascertained only after the fire has occurred. The insurer is liable to make good the actual amount of loss not exceeding the maximum amount fixed under the policy.