How To Repair or Replace A Damaged Mailbox Post

by Mailbox Guru on January 4, 2010

How To Repair or Replace A Damaged Mailbox Post

Although high-quality mailbox posts are sturdy and tested to withstand the harshest weather conditions, there may still come a time when you have to repair or replace yours. 

Removing the old box from the post or vice versa requires a much higher degree of difficulty than removing both at the same time. Allow me to assume that you are here because you wish to replace your mailbox and post. 

Let there be no cement! When you are removing the old post, cement makes detachment harder. Wiggle, pull, wiggle harder, pull harder! Ask someone stronger to do it for you if you must. 

If there is no cement, you can nail or screw a piece of 2×4 or larger lumber to the post at or within a few inches of ground level. Then, using a big pry bar or the mason’s bar, pry the post straight up, using another board, toolbox, or if you’re running out of resources, even your wife or husband as a fulcrum! The latter does not promote a healthy relationship, by the way.

Unleash the MacGyver in you! You may even use an automotive tire jack to lift your mailbox post!

If your post is heavily set in concrete then that is a major issue. Those foundation-like clumps of rocks and gravel mix are most of the time so strong and so when the digging started, you just wish to choose a new location for the box!

You may be left with no option but to move the cement. Sometimes, it’s easier to dig the hole a little wider and muscle the ball of concrete aside. Just install the new post next to it.

US Postal regulations about mailbox location and height

To ensure safe and efficient mail delivery, the US Postal Service has issued regulations regarding curbside deliveries. However, the local post office has the final say in mailbox placement. The old guidelines were:

Vertical height from road surface to bottom of mailbox: Between 41" and 45".

Distance from outside edge of curb or edge of road surface to front of mailbox : 6-8"

These guidelines were in effect since February of 2001.  However, more recent requirements, starting December 9, 2004 are less specific in terms of height measurement and location.  Now the post has to be approved by the local post office and 2) accessible from the vehicle for curbside delivery such that the carrier does not have to leave his vehicle.  That means that any obstruction, including parked cars, snow piles, etc. , give the carrier the right to withhold delivery until the removal of the obstruction. (Click HERE for a complete list of the newer requirements.)

Need to install a post with an extending arm? Base the final position, not just on the arm, but on the box itself!  Make sure that the arm is much higher specifically if you plan to hang the box.  (More details on mounting the box below.)

If you feel your situation is quite different from normal circumstances and would like some exception, kindly ask your friendly postmaster or postal carrier for assistance.

Thinking of creating your own mailbox?  Before going solo…

Make sure you check with your friendly postmaster or carrier to seek approval before you spend time, extra effort, and money on it!  Remember that a poorly or mistakenly designed mailbox can halt your mail delivery! This can cause a lot of trouble!

Choosing your new mailbox post -  Going for wood or not?

You have the option to choose from a variety of mailbox posts.  Plastic mailbox posts are perhaps the most durable. They come in different shapes, colors, and sizes. You can expect to spend less if you choose a plastic mailbox post. That is, if you are not too keen on achieving that classy sophisticated feel that wood or metal posts exude.

Aluminum and galvanized steel
Metal posts are either manufactured from galvanized steel or aluminum. Expect both materials to be sturdy but aluminum is even more dependable. Although more expensive, aluminum posts do not rust and the finish withstands weather conditions that’s why they look new longer.

The traditional choice is of course, mailbox posts made from wood. Those who want to DIY choose wood because it is cheap and easy to assemble. The most inexpensive post is a simple 4×4 or 6×6 post of any wood variety.  A 3/4" – 1" thick pine, plywood or cedar wood base is attached to the top of the post and the mailbox is securely screwed onto it.  The base should fit into the recess under the mailbox.  On most boxes, you will need to leave some space at the door end of the base to prevent rubbing.  Test the door mechanism before making the final box installation.

If you have a bigger budget and want a more fancy post, you can buy wood posts with a horizontal arm, complex supports and other ornamentation and features (of course, you can always build one yourself).  These are available in redwood, cedar and various untreated and pressure-treated woods. 

Wood types have their advantages and disadvantages:

  • Cedar and redwood are expensive but proven to be insect resistant. However, it will eventually rot if buried.  To get the most out of your money, use an underground preservative (see next section for details) applied right to ground level to keep your cedar/redwood post looking great for a long time.

  • Untreated woods, e.g., Douglas fir and pine, can be used for mailbox posts but would require preservatives both above and below-grade.  Warning: They are not insect resistant and they rot quickly.

  • Pressure-treated wood is much more recommended as it has high resistance to rot and insects due to the infusion of a powerful preservative and will last longer underground than any other wood type.  However, it still needs to be coated with a protectant above ground. Otherwise, it may crack, twist and split! If you would like to learn more about pressure-treated wood, click HERE!

  • If you are planning to build a masonry mailbox post and/or include granite, concrete, stone or brick, make sure it conforms to both local or state code as well as postal requirements.  Safety comes first at all times and you don’t want your state or town to consider your post a community hazard! You could be spending hundreds of dollars when you are summoned to act on its immediate removal.

Underground Preservative for a Well-Prepared Mailbox Post (for Burial)

Fact: Creosote is definitely out!

Welcome to the New Age of Pressure-treated Mailbox Posts! They do not rot even after many, many years! Except maybe if they’ve been exposed to abnormal and extreme conditions of moisture, snow plow or injuries. 

Thinking of using Cedar? Sorry but give it over 36 months and you will see your $200 post being eaten by ants and worms like there’s no tomorrow! 
If you’re still on the lookout of quality underground preservatives, you can try Termin-8 by Jascoor Termin-8.

Another product that is new in the market but likewise works well is Woodlife Creocoat from Wolman

The end of your post is most vulnerable to water damage. Pour some of the preservative in a small pail and set the post into it to soak as long as you can… preferably overnight. For best results, cut off a few inches from the end of the post immediately before soaking it. Don’t forget to coat the rest of the post right up to ground level.

DO NOT install a mailbox post in cement unless absolutely necessary!

The reason is obvious! There will come a time when you will get tired of your mailbox post and would want to replace it with a newer model. How can you remove 160 pounds of rock-hard concrete mix, buried 18" into the ground, without breaking your back?!

Think about your health, please.

If you are particularly installing a fancy ornamental iron post, which generally don’t stand upright very well in soil despite what it says on the box,  you can use cement… but just enough to stabilize the post, again, just enough!

Don’t Go Way Too Deep in Digging the Hole! Here’s How to Do It Easily.

To tell you the truth upfront, there isn’t an easy way. But we just don’t quit the fight, do we? Purchase or rent a post hole digger so you disturb a minimum amount of soil.  The hole should be no more than 18-24" deep.   Don’t go way too deep, it’s just a mailbox post we’re about to bury!

For rocky soil, you may need a long mason’s bar, a rounded heavy steel bar from 4′ to 6′ long, flattened to a wedge-shape on one end. This can be used to pry out rocks and the flattened butt end can be used for tamping.

Adding gravel, leveling the mailbox post and filling the hole in steps…

For Cedar Posts: To improve drainage and to keep water from pooling at the bottom of the post, it’s recommended to put 4-6 inches of gravel (or any bunch of small stones) in the bottom of the hole.

Check the level of your mailbox post all the time. A leaning post is not really attractive, is it? Don’t put the level on the top of the post… the top might not be square!  Always check the level from the side.

You can screw or clamp boards to the post to hold it upright.  Or wedge a few rocks around the post in the hole for temporary support.  Or just hold the new post fairly level as you begin filling, making minor corrections as you fill.  (You can always ask the kind help of your family and neighbors if they are willing!)

Filling the hole around the post should be done in steps, packing or "tamping" down the soil as you fill around the post, 6-12" at a time. The post may be loose If you wait until the hole is full before packing. You can use almost anything that will fit into the hole to pack the soil… a shovel handle, the but end of your masons bar, 2×4, etc.   Just keep checking that level!!

Installing your mailbox on the post

You have two methods to choose from, depending on whether you want to mount your box directly atop the pole or onto the top of an extended arm, or if you want to hang the box beneath the extended arm

Don’t ever nail the mailbox to its support… always use galvanized or stainless-steel screws.  If your mailbox does not outlive your post, you want it to be easy to remove.  Galvanized square-drive decking screws are a great choice.

(1)  Mount a board directly on the mailbox post or on the arm extending from the post
If you don’t have a board for the post, you must cut a piece of ¾" plywood or pine that will fit into the base of the mailbox. It should be a tight fit widthwise so the box doesn’t bend when you screw it on, and short enough in length so the box door doesn’t hit the board when the door opens. Position the board as you like it on the post or arm and secure it with at least 4 wood screws. You can use #8 or #10 galvanized square drive screws, 2½" -3" long. If you are using a post with an arm, you may want to let the board overhang the end of arm for clearance of the door.

(2)  Hanging the mailbox under an arm extending from the post
You can buy a special set of bolts designed for hanging a mailbox from your local hardware or home store. The special set consists of an eye bolt and an screw eye, interlocked and ready to use. The eye bolt is screwed into the underside of the post arm and the bolt is attached to the top of the mailbox.  It may or may not come with a rubber washer to seal the outside of the hole.

If these parts are not available from your hardware store, you can either (1) use an eye bolt on the mailbox and a hook on the post arm, or (2) use an eye bolt and screw eye of the same size and bend either open to allow you to hook them together… then bend them closed. For each eye bolt, you should get two nuts, one for inside and one for outside the box, and a small rubber washer (a faucet washer will do) slightly larger than the nut, for the outside to prevent leaks.

Determine the location of the eye bolts on the box first. Some mailboxes have indentations or raised areas to indicate the suggested location for the eyebolts. Locate and drill the holes in the mailbox. Hold the box up under the arm in the position you want it, and use a pencil to transfer the location of the front-most hole you just made to the underside of the arm, being sure to center it along the width. Measure between the holes on the mailbox, and use this measurement to locate the second hole on the arm. Predrill both holes and install the screw eyes.

Put one nut on each eye bolt, and then push on the rubber washers. Bore out the centers of the washers with a drill if they are too tight for the bolts. Then put the eye bolts through the holes in the mailbox and secure them with the remaining nuts, tightening securely.

NOTE:  You can use a dab of caulk instead of a rubber washer.  The washer, however, will probably last longer.

More interesting facts! Mailbox numbers, etc.

  • Your street address number is required on the side of the box or post. It should be clearly visible and facing an approaching mailman. 
  • If your box location is on another street (for example, if your home is on a corner), regulations require that both the house number and street name be on the box or post. 
  • You do not have to put your name on the mailbox unless you want to for a more personalized effect. 
  • Placing offensive graphics, caricatures or effigies intended to ridicule or disparage an individual or group of people is obviously and strictly prohibited.
  • Advertising on mailboxes is also not allowed.

Previous post:

Next post: