What Constitutes a "Major Renovation"?

A "major renovation" would occur anytime the condition of the wall is being modified where the existing wall-mounted mailboxes are presently installed.  If the rough opening of the wall is modified, the renovation would be considered "major" and mailboxes complying with the new USPS STD-4C regulation should be installed.

If you have any questions about which USPS mailbox standard should be applied to a specific project requiring "USPS Approved" mailboxes, please contact the local Post Office for assistance prior to purchasing your mailboxes.

How Do the New Regulations Affect How I Buy Centralized Mailboxes?

The quesitons below will help you determine the right wall-mounted mailbox product for your project.

1. Are the mailboxes being used in new construction? 
a. Only "4C" rated wall-mounted mailboxes or free-standing Cluster Box Units (CBU's) can be used.

2. Are the mailboxes being replaced using the same rough opening (R.O.) for renovation?  
a. "4B+" rated horizontal mailboxes or vertical mailboxes can be used. Contact your local postmaster for details. 

b. If the rough opening will change, then new "4C" rated mailboxes must be used.

Front View of 4B+ Horizontal and Vertical Mailboxes in Wall
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