If you have a domestic, or house insurance policy, in the terms and conditions, it will state that normal cover applies, as long as the home is not empty for either 30, 45 or 60 consecutive days, depending on the insurer.
If you have a commercial building insurance policy, you will find that it is slightly more restrictive. Again, it depends on the business insurance company that you have, how restrictive the terms are if your building is empty.
You can either have a policy that is normally for a tenanted property, which will automotically restrict cover as soon as the property becomes untenanted.
The other option, is to have a policy that is specifically designed for unoccupied building insurance. The insurers are aware at inception, or the start, of the policy that the property is empty, so you are clear straight away about what cover you do, or do not, get.
Some insurers are very cautious and will offer fire, lightning, explosion, aircraft and property owners liability. Given the number of unoccupied properties that are spread throughout the land, certain insurers have seen this as a bonus and have designed wider ranging products that give better cover.
You may have to pay more money, but you can get storm, theft and malicious damage cover. You will never get fixed glass cover, because empty buildings, unfortunately, attract vandalism. Burst pipes cover can be bought, but this can be an expensive option as it is only provided if you drain down the tanks and the water pipes.
To get the best cover, speak to a broker.