Did a new home today. The gas water heater had a single wall vent that went through the ceiling of the garage into the attic. Inside the attic, the single wall vent ran about 8 feet and connected to a B-vent and traveled about 25 feet to exit through the roof. The run of pipe was only supported at the ends. The joints for the vent sections were taped.
Question 1: can a single wall vent pass into the attic at all?
Question 2: can you use tape on the joints?
Question 3: Is there a c-de that specifies the support distances?
Pics attached. Thanks for your help.
P.S. The guy who did this work was the electrician, plumber, and HVAC contractor. All those systems had problems.