So you want to use an in-ground post for your mailbox install, but 12" isn't enough depth? Never fear- you can always add more length.
Contents
How to lengthen your post depth
About curbside installations
The most common installation for a mailbox installation is on an in-ground post. The In-Ground Posts we offer are 43″ in length, which allows you to install them 12″ in the ground, leaving 31″ above the ground above the road surface.
But how does this allow you to have your mailbox 41″ – 45″ above the road surface as required by USPS? The key is that for locking mailboxes, the USPS wants the incoming mail slot or bin-- not the bottom of the mailbox-- 41″ – 45″ above the road surface.
The incoming mail slot or bin on the Mail Manager, Mail Boss and Package Master are 11″ – 13″ above the floor of the mailbox. So, installing these mailboxes on an In-Ground Post buried 12″ in the ground places the incoming mail slot or bin 42″ – 44″ above the road surface.
How to lengthen your post depth
Perhaps you have a deep frost line, or a very heavy installation, so you need more than 12″ in ground for additional stability. No problem!
The bottom of the In-Ground Post has four predrilled holes in it, so you can easily secure a treated 4″ x 4″ wooden post inside of the In-Ground Post to add additional length. If you would like to go 24″ into the ground, place the treated wooden post inside of the steel post leaving 12″ sticking out, and bolt the wooden post to the inside. This allows you to still leave the necessary height of the steel post above the road surface to meet USPS specifications.
What if you need more height?
Maybe you have an unusual application. Perhaps the ground surface you are installing your post in is below the road surface or your postal carrier has requested your incoming mail slot or bin be above the standard requirements.
In this case, you will want to use a treated wooden 4″ x 4″ post inside of the metal post. You can bury as little as 3″ – 6″ of the metal post in the ground, with the rest of the in-ground length provided by the wooden insert. You can play around with the length as necessary.
Height and depth extenders
Our Post Height Extension, and Post Depth Extension allow you to quickly and easily extend the height and/or depth of our in-ground post. The Post Height Extension will raise the height of your post six inches once installed. It can be color matched to your existing post and easily installs with the included hardware. The top mounting pattern fits all Mail Boss brand locking curbside mailboxes, and is ideal for landscape changes or when the mailbox is mounted too low to the ground.
The Mail Boss Post Depth Extension is perfect for increasing the length of any of our steel posts. The extender can be bolted inside the post at variable heights. Holes are pre-drilled at set distances of 3″ apart, allowing for various installation heights. Optionally, at the bottom of the post depth extension, there are 4 sets of aligned cross holes, which accommodate up to 4 sections of #4 rebar (1/2″ Diameter).
Avoid measurements, save time, and shore up your install with the Mail Boss Post Depth Extender.
Still Have Questions?
Don’t hesitate to contact us with additional inquiries!