Update as of 2÷1÷14: our dryer wasn’t drying clothes as fast as it should have, so after re-working the duct and getting a clean bill of health from the dryer repairman, we asked Al to stop by and take another look at our two-story dryer vent. He happily agreed to stop by and climbed up on the roof to clean the vent from the other direction. He also strongly advised us to reverse the ducting change we had made. The combination of his second cleaning and the change seemed to do the trick. Kudo’s to Al and Enviro for his no-charge service after the sale… we are fans!