A mailbox post is a pretty simple structure. You need a vertical post to go in the ground and a horizontal piece to support the mailbox.
The way you join them can make the structure both sturdy and attractive.

A half-lap joint is a great way to do that with dimensional lumber:

• Using a circular saw, cut lines half the thickness of the 4×4 post and exactly the width of the post at the point where the vertical post where the horizontal piece will cross it.
• Make cuts every eighth inch or so in between those lines.
• Chip out the remaining wood by tapping with a hammer.
• Repeat this process on the horizontal piece.
• Fit the two notches into each other at a perfect 90-degree angle. Use a few deck screws to keep them in place.

Although not necessary, you can add diagonal support under the side that will support the mailbox.

Finally, cut a piece of three-quarter-inch-thick dimensional lumber to fit into the recess under the mailbox. This will make it easier to attach the box itself to your sturdy new mailbox post.

Watch the video above for detailed instructions.

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Danny Lipford


Danny Lipford is a home improvement expert and television personality who started his remodeling business, Lipford Construction, at the age of 21 in Mobile, Alabama. He gained national recognition as the host of the nationally syndicated television show, Today's Homeowner with Danny Lipford, which started as a small cable show in Mobile. Danny's expertise in home improvement has also led him to be a contributor to popular magazines and websites and the go-to source for advice on everything related to the home. He has made over 200 national television appearances and served as the home improvement expert for CBS's The Early Show and The Weather Channel for over a decade. Danny is also the founder of 3 Echoes Content Studio,, and Checking In With Chelsea, a décor and lifestyle blog.

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