The house I’m in had a couple of screens with serious holes in them. It looked like vines had grown up and sent anchoring tendrils into the screen and someone had attempted to rip the vine off. The vine was gone and so were patches of screen.
I have replaced screening before. It’s any easy job anyone can do. You need a spline (the rubber stuff that holds the screen in the frame), a spline roller, and screen. The spline and the roller will cost you about $3 or $4 and a roll of 36″ by 25′ fiberglass screen should be around $15.
Family Handyman has a great how-to at http://www.familyhandyman.com/DIY-Projects/Doors—Windows/Window-Repair/how-to-fix-a-window-screen/View-All. I can’t do a better job than they did so I will refer you to that for instructions. They had the great suggestion of putting a brick in the center of the screen so you don’t get it too tight and warp the frame. I used heavy books instead.
Just be careful when you’re cutting the excess screen off and don’t slice your finger like I did…
This is one of my almost completed screen — I have one side left to cut the excess screen off. You can see the books I used as a weight over to the right and the left over spline to the left.
The screens look great and I can open the windows now 🙂