A system for securing a hydrant to a roof of a building is provided that includes a hydrant support that rigidly interconnects to the roof deck. In addition, a method of sealingly interconnecting a standpipe of the hydrant to the hydrant support is provided wherein a plurality of seals are employed. In order to enhance the seal provided between the standpipe and a hydrant support, a boot may be used that covers the interface between the standpipe and the hydrant support.