Section 4: Mailbox Hardware

Introduction

This section presents common information associated with mailbox hardware. The mailbox standards sheets (MB-15(1) and MB-14(2)) contain detailed information about mailbox hardware, DHT numbers, and installation guidelines.

Types of Supports

There are two general types of mailbox supports and specific hardware associated with each type of support:
  • Single Mailbox Support:
     Any of these supports can be used to support a single mailbox.
    • Thin-wall Steel Tube:
       A 2 to 2½ inch diameter thin-wall steel tube. This type of post can be used with a small, medium, or large sized mailbox.
    • Wing Channel Post:
       A 2 pound/ft wing channel post. This type of post can be used with a small or medium sized mailbox.
    • Recycle Rubber Post:
       A rubber post. This type of post is used only for a small size mailbox.
  • Double Mailbox Support:
     This support is used to support two mailboxes on a single support.
    • Thin Wall Steel Tube:
       A 2 to 2½ inch diameter thin wall steel tube.
    • Wing Channel Post:
       A 2 pound/ft wing channel post.
  • Multiple Support:
     Either of these supports can be used for three or more mailboxes.
    • Coat Hanger Support:
      A 2 inch diameter thin-wall steel tube support frame that has a shape similar to an upside down coat hanger. See Figure 9-8.
    • Constant Radius Support:
      A 2 3/8 inch diameter white powder-coated semi-circular pipe with a constant radius. See Figure 9-9.
Coat Hangar Multiple Support (click in image to see full-size image)
Figure 9-8. Coat Hangar Multiple Support
Constant Radius Multiple Support (click in image to see full-size image)
Figure 9-9. Constant Radius Multiple Support

Types of Foundations

There are six types of foundations. Table 9-2 lists the foundations and indicates which type of foundation is used with each type of support.
Table 9-2: Support and Foundation Combinations
Type of Support
Type of Foundation
V-Loc
Wedge Anchor
Driven
Concrete
Embedded
Temporary
Thin-Wall Steel Tube
Type 1
Type 2
No
No
No
No
Thin-Wall Multiple (coathanger)
Type 1
No
No
No
No
No
Wing Channel
No
No
Type 3
No
No
No
Powdercoat Steel (constant radius)
No
No
No
Type 4
No
No
Recycled Rubber
No
No
No
Type 4
No
No
4 x 4 Wood
No
No
No
No
Type 5
No
Plastic Drum
No
No
No
No
No
Type 6
Figure 9-10 illustrates the orientation of the supports/anchors relative to the direction of traffic. Where a wedge is used, it is installed on the side of the support nearest the direction of traffic.
Orientation of Supports/Anchors for Single/DoubleMailbox Installations (click in image to see full-size image)
Figure 9-10. Orientation of Supports/Anchors for Single/Double Mailbox Installations

Mailbox Bracket

The TxDOT universal mailbox bracket provides a single bracket that can be used to mount a small, medium, or large mailbox to a single or multiple support. Figure 9-11 illustrates the basic mailbox bracket. The extensions are used only with a medium or large mailbox. Bolts with a 3/8 inch diameter should be used to provide a tighter fit and prevent the mailbox from rocking. Figures 9-12 to 9-15 illustrate the attachment of the bracket to mailbox supports.
Mailbox Bracket (shown upside down) (click in image to see full-size image)
Figure 9-11. Mailbox Bracket (shown upside down)
Attaching the Bracket to a Single Support (click in image to see full-size image)
Figure 9-12. Attaching the Bracket to a Single Support
Use of the Adapter Plate for a Double MailboxInstallation (click in image to see full-size image)
Figure 9-13. Use of the Adapter Plate for a Double Mailbox Installation
Attaching the Bracket to the Multiple Support (click in image to see full-size image)
Figure 9-14. Attaching the Bracket to the Multiple Support
Bolting the Bracket to a Multiple SupportTube (click in image to see full-size image)
Figure 9-15. Bolting the Bracket to a Multiple Support Tube
The following list of tasks provides step-by-step instructions for putting the bracket together:
  • Attach extension bracket (if required):
    • For a small mailbox, no extension brackets are used.
    • For a medium mailbox, an extension bracket is used on one side only.
    • For a large mailbox, extension brackets are installed on each side.
  • Bolt angle brackets to bottom of mailbox bracket:
    • See Figures 9-12 and 9-13 for orientation with a single or double mailbox support.
    • See Figures 9-14 and 9-15 for orientation with a multiple support.
  • Bolt bracket to mailbox.
  • Bolt assembled bracket/mailbox to support.