You can get a gauze fabric at like 60p/m. You could make a nice recessed frame to hold it and hide the edge. There's tables online of particle size so you can p

You can get a gauze fabric at like 60p/m. You could make a nice recessed frame to hold it and hide the edge. There's tables online of particle size so you can pick a mesh size. Got some to use over windows and air vents. Works great and so cheap it's just replaced instead of cleaned. Airflow on the finer sizes would be interesting. Mines a spider guard.