I don't think I've ever come upon anything as useful and as clever as these winter homes for kitties. If you belong to a rescue group wouldn't it be fun to have a 'work bee' one evening and make a bunch of these for the homeless kitties you know? They'd also be a super fund-raiser for an animal charitable group.
For those of us that are not handy or don't know anyone that is handy with power tools this is a fast, easy and cheap way to help the homeless kitties make it through the winter.
Fast and functional, this is an innovative idea, costing around $30.00, less if you can find some pieces in yard sales and second-hand shops. Finding one plastic bin to fit inside another is the most challenging part of this project. One container should fit inside the other with room still left for polystyrene.
The inner box is an 18 gallon Rubbermaid 'Roughneck Tote' - Lowe's part number: 44894 - cost $5.00. The outer box is a 35 gallon Rubbermaid 'Latching Tote' that is a bit more difficult to find - Lowe's part number: 212261 - cost $15.00. In addition, 1 inch polystyrene sheets - cost of about $10.00 for a total of about $30.00 depending on your product sources.
If you have difficulty cutting the durable plastic, blew hot air from a hairdryer on the area where you wish to cut. The plastic will 'cut like butter'.
For additional warmth from the winter winds, consider surrounding the shelter with bails of straw. Homes insulated with 18 inch wide bails of straw can save up to 75% on heating & cooling costs. Just think what that could do for the cats!
Place shelters where they will be protected from wind and snow drifts -- particularly those without protective flaps over the door(s) -- otherwise snow could blow in and bury or trap the cats. If there are fixed objects, such as buildings in your feral cat shelter area, pay attention to the way the winds tend to circulate, and place the shelters where there is the least amount of blowing & drifting snow. This could be a lifesaver, particularly for those who endure extreme winter weather, where roads may be impassable for 1-2 days.
Depending on predators and other animals or hazards in your area, some cats may not use shelters unless there are two exits -- one for them to sneak out should another unwanted animal enter. Consider an emergency exit with a flap that opens from the inside only.
Happy building! I know that the outside kitties will be so thankful for their cozy homes.