Definitely!! When I first got this house in tropical Nth Qld, I put in Air-conditioning and Insulation! The roof has the highest grade Gold Batts,and the walls are also done,though with very,dense(in fact, extremely so,purpose made styrene foam which was part of the deal when I had the place vinyl clad!! The house was instantly cooler in the warm months and much warmer in the cool ones,PLUS when I use the air con it is so much more effective as the cool air stays inside the house! This also means that I do not need to use it so much,and also my power bill is cheaper because of the insulation! Great Investment!!