Flooring material comprising sheet-shaped floor elements with a mainly square or rectangular shape. The floor elements are provided with edges, a lower side and an upper decorative layer. The floor elements are intended to be joined by means of joining members. The floor elements are provided with male joining members on a first edge while a second edge of the floor elements are provided with a female joining member. The male joining member is provided with a tongue and a lower side groove while the female joining member is provided with a groove and a cheek, the cheek being provided with a lip. The floor elements are provided with a male vertical assembly joining member on a third edge while a fourth, opposite, edge is provided with female vertical assembly joining member.