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Itching Inside the Screen Porch? It's No-See-Ums.

Getting bitten inside your screened porch? It's No-See-Ums (Sand Flies). Learn why standard screens fail and how 20x20 mesh stops them.

September 05, 2025 1 min read

Cluster of red itchy bites from biting midges on legs

You spent $5,000 screening in your porch. You sit down with a beer. Ten minutes later, your legs are on fire. You look... but see nothing.

You are victims of the "No-See-Um" (Biting Midge).

Why Your Screens Failed

Standard window screens have a 18x16 mesh. Mosquitoes can't fit through that.

But No-See-Ums are microscopic. They are so small they fly right through standard mesh like it's an open door. They laugh at your expensive porch.

The Bite

They don't just poke you like a mosquito. They have saw-like jaws. They slice the skin and spit anti-coagulant. That's why the itch is so intense and lasts for days.

The Fix: 20x20 Mesh

If you live near water (salt marsh, lake, or swamp), standard screens are useless. You need to re-screen with 20x20 mesh (often sold as "No-See-Um Mesh"). The holes are tighter.

The Ceiling Fan Trick

Midges are terrible flyers. If you don't want to replace your screens, turn on a strong ceiling fan. They can't fly in the wind current. It's the cheapest repellent there is.