What is an area bed?
An area bed is an infiltrative zone similar to that of a filter bed. It generally consists of a clean stone layer 250 mm thick underlain by a sand layer 200 – 300 mm thick. The area bed may or may not have a distribution network of PVC laterals, depending on the technology. Some area beds are located directly beneath the treatment units themselves, which helps to save space. Area bed authorizations are not contained in the building code, rather they are granted by the Building Materials Evaluation Commission (BMEC). Area bed authorizations are technology specific and cannot be used with every alternative technology. Minute differences in area bed authorizations are present from one technology to the next, so you must consult the authorization for the technology you wish to install for specific area bed requirements for that technology. Area beds have very small footprints, are are only allowed in conjunction with alternative treatment units providing tertiary level treatment.