A little background: I recently invested in 5/16 nylon netting for the tops of my runs. It's nylon with 40# breaking strength. I installed it over the top of the existing 2" chicken wire. I did this because I'm sick & tired of battling MITES with my birds and I KNOW the sparrows are the culprits! Plus, they are POOPING on EVERYTHING in my coop, my lights, my door handles, my feed, my brooder!! ARRGHH! Last spring, I started feeding my chickens inside the coop (made the mice worse) then I put a cat in the coop overnights. Mice 0, cat 5. Then, the sparrows moved in! Butters (the cat) is outside during the day and the sparrows move in as soon as he's outside. A few weeks ago, I went & bought a canvas tarp at Home Depot. I cut out little squares, then made strips out of the squares and made "doors" for my pop holes-- thinking it would discourage the birds. At first, I tied back about 1/2 of the strips on each door until the chickens were comfortable and had figured it out...then I slowly let more of the strips down and now each door has the strips...alas...the sparrows would wait until there was a bump in the fabric and fly right in! So then I bought this nylon netting. It is 5/16 of an inch opening. I used it to cover the tops of my run which used to be 2''. I did leave the 2'' up. Now, the sparrows have been unable to get in (the sides of my run are hardware cloth & 1" wire). However, my hubby wants me to take it down for the winter because of the snow...(which really defeats the purpose of keeping the sparrows out!) Does anyone have this type of wire in a heavy snowfall area??