One of the more difficult things a poultry enthusiast may encounter is the attraction of rodents into the coop. Most often mice can be stopped using baits and traps but rats are a more difficult battle if coop floor design is ignored. If you have a concrete floor then you are among the lucky 20% of poultry enthusiasts the rest are dealing with wood or wire or dirt floors or something in between. For those who want to prevent rats and other burrowing rodents from making their home under your coop here is a cost effective way to create an effective barrier under the floor. Save your glass jars and bottles. Yes save them as they are valuable building materials. Old timers I knew never started a new coop without a good supply of glass. Broken windows, jars, bottles it's all good material to break up and use to prevent rodents from taking up residence under the coop. If you are smart you have saved your feed sacks instead of throwing them away as they make breaking up the glass a safer process. Place your jars, bottles or window glass in a feed sack or several paper backs and break the glass up into shards. Accumulate the glass shards in a metal trash can as this is the safest place. For an 8'x10' coop you need about two inches of broken glass under the floor and this takes about 3 trash cans full of glass. Clearly this takes planning and time to accumulate. Old timers even used this broken glass method under concrete as an additional layer of protection. Under a wooden floor you want to lay the glass two inches thick and secure it to the ground with hardware clothe or wire or mortar it in place before starting the foundation. if you are putting sand or mulch in your run then put the glass down and then put hardware cloth on top of the glass before placing 6 inches of sand or mulch on top of the wire. In this method you want to make certain no glass is protruding through the wire before placing your mulch or sand to make this even more safe I use 1/4" hardware cloth instead of the standard 1/2" cloth. I also use a glass barrier 18 inches wide around the outside of the pens and coops and place plastic hardware cloth on top of it pegged down with wire pins. This prevents all animals from digging under the fence or coop. Especially effective with Red Fox. So if you want to try this method remember to get all friends and family involved with giving you their glass and you'll accumulate it much quicker. Remember old timers were the best recyclers long before it was fashionable and cool!