Summary: Commercial mailboxes are built for centralized storage of mail for residential and business use. Cluster mailboxes are for outdoor use, and horizontal mailboxes are for indoor use unless in a covered area.
A commercial mailbox or set of mailboxes are built to accommodate a centralized mailbox location for businesses and residential blocks. Here is a quick overview of popular commercial mailboxes:
Cluster mailboxes are usually mounted on a pedestal and have several door units for buildings with multiple tenants. Cluster mailboxes are the most popular type of commercial mailbox due to use in residential buildings and small condominiums. With the approval of the postal service, you can install these anywhere outdoors. You can also order special number engraving on the tenant doors to match the numbers of the individual residential units in the building.
When it comes to indoor installations, Horizontal mailboxes are the most popular. The number of units can range from one to as many as thirty on a single installation. The horizontal mailboxes have to potential methods of mounting: surface mounted on the wall or recessed into the wall. USPS regulations dictate that for new construction projects and major renovations use horizontal mailboxes.
Both of the above types of commercial mailboxes are available in multiple colors and finishes. Some types are only available in anodized aluminum. Certain areas will have rules that govern the use and placement of commercial mailboxes, confirm any installations plans with the postmaster before you commence and work.