My dog — a 45-pound terrier mix with strong opinions about squirrels — put his paw through the screen door last summer. The hole was the size of a grapefruit. I looked up replacement screen doors and they started at $80. For a piece of mesh in a frame.

I fixed it for $3.47 and you cannot tell there was ever a hole. Here is exactly how.

Assess the Hole First

Not all screen damage needs the same fix:

• Small tear (under 2 inches): Clear nail polish or super glue. Paint a thin layer over the tear and let it dry. It seals the edges so the tear does not spread. This is not invisible but it is functional.
• Medium hole (2-6 inches): Screen patch kit. $3-5 at any hardware store. Comes with a small rectangle of screen material and adhesive. This is what I used.
• Large or multiple holes: Replace the entire screen panel. Still cheaper than a new door — screen roll is about $10 for enough to do a whole door.

The Patch Method (For Medium Holes)

1. Trim the hole into a clean rectangle or square using scissors or a utility knife. Ragged edges do not hold adhesive well. Cut away any bent or frayed screen strands.
2. Cut your patch material half an inch larger than the hole on all sides. You need overlap for the adhesive to grip.
3. If your kit came with adhesive dots, apply them around the edge of the patch where it will contact the existing screen. If no dots, use clear silicone adhesive — a thin bead around the edge.
4. Press the patch over the hole, adhesive side down. Hold firm pressure for 30 seconds.
5. Let it cure for at least an hour before touching it. Overnight is better.

The patch will be slightly visible — the new screen material is brighter than the old, weathered screen. After a few weeks of sun and dust, it blends in. If you are particular, buy a patch kit in the right color — they come in charcoal, silver, and bright aluminum.

For Fiberglass Screens Specifically

Most modern screens are fiberglass, not metal. Fiberglass does not bend back into shape like metal and it frays at the edges. If you have fiberglass, the clear nail polish trick for small tears works, but the patch method above is more reliable for anything larger than a pinhole.

If the screen is really old and brittle, patching one hole often leads to another tear nearby as the material continues to degrade. If you find yourself patching the same screen repeatedly, it is time to replace the whole panel.

Prevention: The Screen Guard

After I patched the hole, I installed a screen guard — a metal grille that attaches to the bottom half of the screen door. It protects against pets and kids pushing through. They cost about $15-20 at hardware stores and install with four screws. My dog has thrown himself against it multiple times and the screen is still intact.