I know that a lot of people here say outdoor enviroments aren't good for a guineapig but in alot fo cases it is . We have an outdoor enviroment of 2square meters in our garden and there are alot of cats in our neighborhood .We have put pins on the walls the cats crawl over if they attack our guineapigs and since then no cat has entered our garden . Our guineapigs have two wooden boxes in their part of the garden and a dugged in , large stone cave with golfplates on it to keep them dry . We keep the cave dry with hay and we isolated it with plastic against moisture and cold . Allso its never to cold in the winters because we created a little heat tube that gives some heat . It takes 2 minutes to warm up the cave and then we put our guineapigs in it . It doesn't burn em because its too cold for that . I can tell you our guineapigs are very happy with it . I will post pictures later on