Venting Materials question

i see quite often when two appliances are venting into the same chimney that the furnace is vented above the H20 tank. are you guys writing this up as a potential safety risk and that they might not vent properly? i am, but am getting nasty looks from realtors!

How is this a safety issue?

I see the vent penetration as too close to combustibles and as long as the upper vent is smaller than the lower vent, the venting situation is fine.


i guess this picture isnt that great but the lower vent was smaller

Then I’d call it out as such. “See my diagram above”.