Horses have survived for millions of years in the wild, with the only shelter being whatever they could find in the natural landscape for protection. But, as they have become more domesticated, horses have become more delicate and require more care. A fancy barn is not required to keep a horse safe and sound today. You can build a simple one-horse shelter and keep him healthy and protected.
Begin by choosing a spot for the shed that is not prone to flooding. It must be in the highest and driest part of the paddock or pasture.
Bring in sand to a depth of 18 inches to build up a "pad" for the shed. The sand is important to drain away any urine and other fluids that can end up under the roof of the shed. It also will provide a soft, dry bed for the horse.
Cement your 4-x-4 posts to a depth of 24 inches in the corners and at every 12 feet of length for of the shed. These will support the entire weight of the roof, so it is imperative that they be solid and secure.
Frame your shed with the lumber. Remember to make the walls solid lumber to a minimum of 4 feet in height, to avoid the horses kicking through the siding you are about to apply. When framing the roof, place the lumber every 12 inches to make the strongest roof possible.
Apply the siding to the walls and the roof of your shed. Aluminum siding is the most economical and can sometimes even be found as a recycled material. Use roofing nails when securing the roof.
Always take your time and do the best job possible. It is better to spend a little more in the initial phase, than to spend all your time on repair and maintenance.
Make sure you follow the manufacturers' instructions when you use power tools, and wear protective gear.