Guide
The order to arrange self build insurance in
Updated
Self builders arrange insurance when they think of it, which is usually when something prompts them. The order below is the one the project actually requires, and following it removes almost every avoidable problem in this area.
Before anything happens: the warranty
A structural warranty covers defects in the finished house for a period of years, typically ten, and it is what a lender will want to see before offering a mortgage on a newly built home, whether you are selling or refinancing.
It has to be arranged before construction, because the provider inspects at stages during the build. A warranty provider cannot certify what it never saw, which is why this is the one cover that genuinely cannot be fixed later. Self builders who discover this at completion face a house that is difficult to mortgage or sell.
Before the first delivery: site and works
Materials on site are worth stealing from the moment they arrive, and they are usually delivered before anyone starts building. Cover that begins on the build start date leaves that window open.
Check specifically that unfixed materials are covered, because that is the category most often sub-limited, and it is precisely what gets taken.
Before anyone works for you: employers liability
This is a legal duty for employers in Great Britain, and the question of who counts as your employee is broader than most self builders assume. It turns on how the work is directed rather than on how the invoice is worded, so labour-only help and family assisting on site can fall inside it.
Take advice on your specific arrangements rather than assuming that describing everyone as a subcontractor disposes of the question.
At completion: closing the gap
Site and works cover ends and buildings cover begins, and the join is where an uninsured period appears. Arrange the buildings policy before you need it, not after the last trade leaves.
Then deal with unoccupancy. A finished, empty house is a different risk and many wordings restrict cover after 30 to 60 days standing empty. If you are not moving in immediately, that is a conversation to have before the restriction bites rather than after a claim.