Here in the Dayton, Ohio area you can buy them at Lowe's for 19.95. I don't think you could make one any cheaper than that ...and it's a lot easier !!!
Do you just want some ventilation and not much cost? If so, you can just buy a tension rod (two if you want one for the top and bottom) and hang a drapery panel (sheer or lace). You'll get ventilation, and if you move, can take it with you and use it someplace else later. These little curtain tension rods are really cheap and you could probably find cheap panels at a thrift store or yard sale.
For a home? Standard screen doors aren't too expensive, I understand. However, if for another area, remember that you can use patio door screens and drill hinge holes and reinforse the screen with punched aluminum sheeting or wire fencing over the existing screening if not too large. Shade cloth makes a better screen door for sunny exposures IF you have a spline roller? to tighten it in it's track.
I find folks tossing curbside old useable but lightweight screen/storm doors as they improve their properties cosmetically whose frame can be spray painted a med dark bronze or white to freshen it up.
If for a balcony patio door, remember you can weight patio shade cloth/screening, hem the edges by hand and have a draped screen door by adding magnets to the edges so it will catch on the frame of the patio door.
These used patio screens can also be used for drop-down screen doors on a garage door for summer ventilation.
Here's an article I clipped from a do it yourself website and I'm building one for myself next weekend. I'm on a pretty strict budget so I'm using scrap wood from old recycled closet doors (sliding doors). I got a new circular saw for Christmas and can't wait to try it out. Hope this helps!
The site won't let me upload the file but if you email me at lunarmom at gmail dot com, I'll be glad to send it to you!
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