They installed two velux light tubes almost four years ago in our home. Last early autumn and through this winter some dirty water started to puddle in one of the units. Inside the lens. They came out and inspected the installation. Took the lens off and put it all back together. The leak turned out to be from another vent in the roof above the velux installation. It dripped in the attic and onto to velux tube inside the attic and then leaked through an installation screw Strange but leaks usually are. They reseated the vent and went on their way. Talk about customer service. We have enjoyed the velux tubes in a bathroom and laundry that always needed a light on during the day. No more. I highly recommend Eric & sons and the velux tubes.