I had Over the Top Roofing install some ventillation vents. My house was not cooling off and the ac unit was running constantly. OTTR inspected my attic and roof and they said I needed 3-4 vents. I went with 4 of the wind turbine vents. The vents look really good and the installation is clean. It actually rained the next day and everything was dry with no leaks. When I was checking for leaks I could not help but notice the attic was about the same temperatue as outside. I was really suprised as it was an inferno before the vents. The ac unit will actually shut off now and the house is noticable cooler. I'm very satisfied with OTTR and will be recommending them to friends and family.