The cattery is heated however it is not used in the winter.
Both catterys are joined by a tunnel for easy access by all cats and both are self contained on the inside.
http://www.petsathome.com/
http://www.catscratcher.com/
http://www.fabcats.com/
www.hillspet.com/products.html
http://www.gccfcats.org/