Maisonette buildings insurance is awkward because a maisonette is usually half a house, and half a house cannot be insured on its own. The roof, the walls and the foundations are shared with the flat above or below, and a fire or a subsidence claim will not respect the line between the two demises. How this is handled depends entirely on the leases.
The three arrangements you will meet
A freeholder insures the whole building and recharges both maisonettes through the service charge, which is the tidiest. The two leaseholders jointly own the freehold and insure the building through a company or jointly. Or each lease obliges its own leaseholder to insure their part, which is the arrangement that causes trouble and which some lenders will not accept.
Why separate policies are a problem
Two insurers on one structure argue about apportionment on every shared element, and a total loss produces two partial settlements that will not rebuild one building. Lenders dislike it for exactly that reason. Where the leases require it, the practical fix is a joint policy in both names by agreement, which most insurers will write.
What to check before buying
The lease, first: it will say who insures what, and whether the roof and structure are demised or retained. Then whether any existing policy covers the whole building or only one maisonette. Then whether the mortgage lender has a requirement, because several specify whole building cover on maisonettes as a condition.
Letting a maisonette
Where the structure is insured by the freeholder or jointly, a landlord letting a maisonette needs the same package as a landlord letting a leasehold flat: contents, liability, loss of rent and tenant damage, without a buildings section. Where the leaseholder insures their own part, the landlord policy needs a buildings section written on the right basis, which is a conversation to have with the insurer rather than a box to tick.
Questions people ask about maisonette buildings insurance
Can a maisonette be insured on its own?
Not satisfactorily. The structure is shared and a claim will not respect the line between the two demises. Whole building cover is what lenders expect.
Who insures a maisonette building?
Usually the freeholder, recharging both leaseholders, or the leaseholders jointly where they hold the freehold. Separate policies per maisonette cause problems.
What if the other owner will not cooperate?
Start with the leases and the lender's requirements, both of which usually favour a joint policy. Advice is worth taking early rather than after a claim.
Do I need a buildings section if I let mine?
Only where your lease makes you responsible for insuring your part. Where the building is insured as a whole, you need contents, liability, loss of rent and tenant damage.