Originally Posted by horsecrazygirl13
Does it have to go down farther than the frost line? Here it is around 6 feet. It would be impossible to find posts that long.
How much frost heave you get depends a lot on the type of soil you have. If you have soil that drains well, you'll have less heave, and for a horse shelter, I wouldn't worry about a the potential for a couple inches of lift. If you have clay soil where the water sits and freezes, you'll have a bigger problem and using the spikes would certainly reduce the heave.