Onduline is less red mite friendly than felt, and also permits ventilation. A slide out floor makes cleaning easy, or stockboard, being smooth, has fewer hiding places for red mite. We have a variety of run designs, but all have a roof flap to permit drinkers and feeders to be put in the run, and the rest of the run is roofed with twin-wall polycarbonate, which keeps the area dry, lets in light and is also very light to carry. Hexagonal wire is more likely to bulge but is much stronger than the lightweight square sort. A 15cm board around the bottom of the run prevents mud splashing up from around the run and prevents spilled food being thrown out and attracting wild birds and rats.