Horses need shade, they at least deserves a little shade to stand under. You may ask yourself why, when you seldom see them using it, but they do. Horse shade does not always have to be expensive or elaborate. A large shade tree is more than enough in some cases.
Horse shade can be easily constructed out of scrap two by fours and some used aluminum awning panels. This Loafing Shed page shows an inexpensive horse shade being built out of scrap material. This Pole Barn, while a little more expensive, is also excellent protection for your horses.
Tarps can also be used to create shade. They can be attached to any number of structures and give the horse a much welcomed place to get out of the hot sun.
The video below shows how four poles can easily be turned into a horse shade. The fabric is a shade sail made from Sunbrella material but it could just as easily be a sturdy tarp or a specially fabricated shade screen.
The Building Plans on this page could be easily converted into a horse shade. Also found here are plans for barns and loafing sheds. Horses will always need shade, this is true, and these building plans could help you provide it for them.
Doing an Amazon search for ShelterLogic (#ad) will turn up some of my favorite horse shade solutions.