Homes have many things that can either last a long time, or can breakdown only years after purchase or installation. Sometimes with good reason, sometimes because of faulty manufacturing. Alongside the misery of having to replace a roof or a furnace, is the fact that the expense can run you into the tens of thousands of dollars. So how long can you expect the basics in your home to last? Let a knowledgeable and trusted  general contractor  tell you. Roofs : As mentioned in the introduction, roofs are expensive if you need it all replaced. Metal and stone roofs (like copper, slate, and tile) can last 50+ years; wood about 30 years; and asphalt/shingle 25 or so years. It's also important to consider climate when figuring longevity. AC Units : Outdoor cooling units have the worst experience working all day in the heat and sun, especially if they are left to do...