The ground is frozen rock hard, but it is possible to correctly install a mailbox post in the winter.
If you live in a cold weather area, it’s likely only a matter of time until your mailbox is taken out by a snow plow or a sliding vehicle. Then you are faced with the problem of trying to install a mailbox post in the winter season, which is not ideal. You could hire a contractor, but we are DIY people and you just need a post in the ground and your mailbox back up.
If the ground is frozen and/or covered in snow and ice, it’s pretty difficult to dig a hole in the ground or get concrete to set in freezing temperatures. However, there are a couple of ways to get the job done.
If needed right way, you can use a 5-gallon bucket with concrete. Just place your post in the bucket, add a bag of concrete, and then mix in some water. You will need to allow the concrete to cure in your garage or somewhere warm. Be sure to prop the post up vertically so that it doesn’t fall over while curing. Similarly, if you expect your outside temperature to stay below freezing, you can fill a bucket with half sand and half water. Place it outside, again propping the mailbox post up, and allow it to freeze. Then move your bucket and post to your curb. This will be very heavy to move and is a temporary solution. This is not our recommended method, but will suffice in a pinch if you plan on replacing your post later.
Permanent Solutions for Wood Posts
This method involves a metal spike, with an attached post bracket, that you can drive into the ground. These spikes are almost 3 feet in length, with a post collar of just under 6 inches. Because of how deep the spike goes and the depth of the post collar, these easily provide a more than sturdy foundation for a mailbox post. As a result, this method is considered a permanent installation. We recommend the Simpson Strong-Tie EZ Spike because of its quality, but we have not found it at your local big-box stores. It does sell on Amazon for under $30.00.
If you have a sledge hammer or other heavy-weight hammer, your job will go faster. Set your spike in the desired location, place a short 4×4 block into the existing bracket or use another piece of scrap wood, and pound away. Using a piece of wood to pound on is important because you don’t want to damage the bracket that will hold your 4×4 post. Take care that your spike is going in vertically level. You can hold a small level against the side of the top portion of the spike to check yourself, or use a corner level which is made for posts. Once you get it deep enough so that the top of your bracket is ground level, you’re ready for the next step.
If you any have trouble penetrating the ground, try pouring a bucket or two of hot water in the spot where you will place the spike and allow it to soften the ground a bit.
Once your spike is in place, you can then place your standard 4×4 wood mailbox post into the top bracket. If your old post was broken off in or near the ground, it may still have enough length to reuse since you are not going all the way into the ground with it. If you think this may be possible, read our mailbox regulations article for specifics on the correct mailbox height for your post. You can then cut your post to size or slice a small section off the bottom so that your post is flat and straight.
If your post is broken in half or it’s just a good time to upgrade, you can buy a new wood post at any home improvement store. You will want to make sure you choose either a cedar or pressure-treated post as these are the most resistant to rot and insects.
Finally, place your post in the bracket and make sure it’s level and at the correct height. If all looks good, attach screws on the sides through the provided holes. You will need 4-8 galvanized screws. The post will fit snug in the bracket, so the screws are more for holding the post down, not holding it upright.
Some other advantages to this method are that your post will not be in constant contact with the ground or concrete, which tend to rot the post over time. Second, if your post is broken off again or you just want to change your look, you can just loosen a few screws and you are able to pull out your post for replacement. Lastly, the spike will allow you to install the post without creating the damage to your lawn and/or tree roots that digging a large hole would cause.
You could likewise use a “screw-in” ground anchor, such as the Mayne No-Dig Anchor, which sells for less than $20.00. This is the same concept as the metal spike, but this product does not require you to drive the anchor into the ground with a hammer. Instead, you can screw it into the ground using a crossbar.
We have previously written about the screw-in anchor in our article, How to Install a Mailbox Post Without Concrete.
With either method, you will have a nice and sturdy mailbox post once again. Just in case you are wondering…if you are not trying to install a mailbox post in the winter, this method is still equally recommended in the warmer months.
If looking for a way to combat ever having to install a mailbox post in the winter again, check out our article on the popular Swing Away Mailboxes.
Where does one find the hardware and post to get started?