If you live in a moderate or hot climate, a barn with a roll-up curtain on one or both sides can be both advantageous and economical. The roll-up feature allows a cross-breeze in warm weather while still providing overhead shade and shelter. You can easily unroll the curtain in cold weather. A smaller barn, like a single-stall pole barn, is best suited so the wall is not larger than a readily available tarp, and also for rolling ease. A heavy-duty canvas tarp is a good example of an appropriate material for a roll-up curtain.
Roll up the tarp so that the underside is on top, making sure the reinforced riveted edge is the one you grab to unroll it. Carry the tarp and loaded staple gun to the top of the barn on your step ladder and lay the reinforced edge along the top of the girder.
Staple the tarp to the girder, starting in the centre. You can then affix the staples at each rivet, working your way to each side. Allow the curtain to fall to the ground.
Attach two or three bungee cords to the top of the barn, depending on how many poles you have going all the way to the top.
Affix rope or reinforced twine, such as braided bale twine, to the sides of the tarp about halfway down. When the tarp is rolled down you will tie the rope to the poles on each side to prevent it from flapping. You can cut holes in the tarp, lace the rope through it and simply tie them around each pole on the side. When you want to roll up the curtain, simply untie and remove the rope, and then tie the rope around the pole for safekeeping until you unroll the curtain again. Or you can insert a bungee cord in each hole, wrap around the pole and hook the bungee cord back onto itself.
Affix bungee cords to the bottom reinforced edge of the tarp at the sides and wrap them around each pole, hooking the bungee cord back onto itself. This anchors the curtain when it is rolled down. If your structure has a pole or vertical stringer in the centre of the wall, add a bungee cord to the bottom centre rivet to secure the curtain in the middle.
You can do this using the same bungee cords for the top and the bottom, but having separate sets is an additional convenience. When you roll up the curtain, simply remove the end of the bungee cord and hook it into the rivet or hole in the bottom edge of the curtain, which is now along the top of the barn, to secure.
A canvas tarp is preferred, but you can use a heavy-duty vinyl or plastic tarp as well. A danger of using a plastic material is the ease with which it blows in the wind, and the noise it makes, which can scare certain animals such as horses.