Anytime you build something out of wood you expect it to last a long time. That may be true for desks or tables that are meant to remain inside but not so for those that will spend their days outside in the cold rain and snow. The elements will break down the strongest of woods in just a few short years. Stains and sealants will prolong the life of any wood project as long as it is done properly. I have installed many fences and decks and the one problems that always show up are twisting and warping of the wood. Gates have an additional problem – sagging. The weight of the wood itself will pull nails and screws, which opens cracks in the wood. The twisting and warping adds and compounds the effect on the gate’s structure. This is a common problem with pressure treated pine. As the pine dries out its shape begins to change.

Over the years, I have repaired many gates that had this sagging problem. Some gates were built by others and some built by me. This process was getting very frustrating. My first line of attack was to tear them down and rebuild as they were before, but using longer screws. Some of the gates were fine but signs of sagging would eventually show up.

One day I was at The Home Depot and saw a system where the gate was built using brackets holding the 2 x 4s together. The design was practical and would work but it seemed to be a lot more structure than necessary. While in the shelving department I discovered the new way I would build my gates. No longer would I have to use a 2 x 4 on a 45 degree angle for support. My fix utilized regular shelving brackets. The brackets connect the frame of the gate together and are much stronger because they are designed to hold weight. Ta Da! See if this will work with your next sagging gate. (DC)
How to design a wood gate that won't sag.