We returned from the Christmas break today only to find our kitchen under water. We've lived in this house for 10 years and not once had a leaky roof. Last summer my husband decided it was time to add a new roof. The roofers set down a new roof on top of the old one and, to say the least, I was not happy with how it looked. What's worse, we now have a horrible leak. We've never had a leak before. It's dripping through the vents and door jams. I've spent the evening researching roof overlays and would like to say one thing: NEVER put a roof on top of a roof. Do it ONLY if you have an experienced roofer who does it routinely. Make sure they repair the underlying roof first, install all flashing first, and lay the roof according to manufacturer instructions. If you want to know more about roofing, I've included a link in the title above.
roof overlay, roof installation