SylvanLMP
Please note that in our locality we must conform to the 1997 IPC.
Reference section 905.3 and 905.4 – Vent Conections and Grades. My Question is this:
I recnetly had to install a dry vent on a water closet. I rolled up with a 4×2 wye on a 45 degree angle, then proceeded to the wall behind the toilet to contiue in the vertical (Approx 20″). What is the intent of the above listed code, and is this installation a violation of the code? Thanks in advance for your input.
Regarding 905.3 my personal interpretation would be this Mickey mouse code wants to make sure the vent line is above the center line of drainage as most sanitary/waste lines are designed to run no more then 50% of capacity and thus little possibility of the vent being blocked by waste.
So far they are right on the money
Regarding 905.4 All fixtures should be vented above the “flood level rim” not the over flow.
This is to prevent the vent lines from becoming a drain line during a blockage.
Point of information IMHO ONCE you see a code saying “wet vent” other then possibly acid waste systems you know from the get go this code is one of the worst going and has no place in a civilized society BUT the Almighty dollar and politicians who can be paid for do sell out to the highest bidder case in point AAV’s and wet venting.
Good luck as any code that allows circuit venting you know does not really take public safety seriously 
