Now there is a planning law restricting garden buildings to 2.5m high (if they are within 2.0m of a boundary, which they mostly are - the only other choice is to apply for planning permission), the flat or pent roof summerhouses are becoming more popular because apex rooves don't look quite right as the pitch is just too flat.
Supplied with EPDM rubber roof sheet for a long-lasting solution for what is normally a weak point of a flat roof structure.