The building itself is constructed entirely of English oak, with mortise and tenon joints and is, in this sense, an "authentic" 16th-century timber-framed building as no structural steel was used. The seats are simple benches (though cushions can be hired for performances) and the Globe has the first and only thatched roof permitted in London since the Great Fire of 1666. The modern thatch is well protected by fire retardants, and sprinklers on the roof ensure further protection against fire. The pit has a concrete surface, as opposed to earthen-ground covered with strewn rush from the original theatre. The theatre has extensive backstage support areas for actors and musicians, and is attached to a modern lobby, restaurant, gift shop and visitor centre. Seating capacity is 873 with an additional 700 "Groundlings" standing in the yard, making up an audience about half the size of a typical audience in Shakespeare's time.