Gregg G
Member
New construction. Question regarding proper way to tie different vent line sizes together. On one end
of the house is a full bath - tub/shower, toilet, single lavatory. The 2" vent from this bath is routed
horizontally about 40' (straight line with 1/4" / foot grade) and is supported every 48" with J-hooks.
At 40', there is a 1-1/2" vent line from the kitchen sink/dishwasher that needs to tie in with the 2"
bath vent at 90 deg. I know that for drain lines, a sanitary tee is only used for horizontal to vertical
connections - never for horizontal to horizontal.
Is it okay to put a 1-1/2" x 2" x 2" san tee on its side to connect these vents? In my location the
local inspector wants all of the vents to have 1/4" / foot grade, so my thought was to roll the san tee
down a little bit so that the 1-1/2" vent would have the correct grade. Or should I use a 1-1/2" x 2" x 2"
wye fitting instead? It doesn't seem like it would make any difference for "air", and if there was a little
rain that got into the roof vent, wouldn't that moisture travel down a san tee just as easily as a wye?
I need to get "supplies" in the next day or two, so either way is just as easy. Just like to know what is
"correct".
Eventually, the 2" line will merge into a 3" roof vent. I've been told to make sure not to merge too
many DFU into a 2" line, but rather directly into the 3" line. I think the 1-1/2" kitchen sink and
DW vent are okay into the 2" bath vent though.
Kind regards!
Gregg G.
of the house is a full bath - tub/shower, toilet, single lavatory. The 2" vent from this bath is routed
horizontally about 40' (straight line with 1/4" / foot grade) and is supported every 48" with J-hooks.
At 40', there is a 1-1/2" vent line from the kitchen sink/dishwasher that needs to tie in with the 2"
bath vent at 90 deg. I know that for drain lines, a sanitary tee is only used for horizontal to vertical
connections - never for horizontal to horizontal.
Is it okay to put a 1-1/2" x 2" x 2" san tee on its side to connect these vents? In my location the
local inspector wants all of the vents to have 1/4" / foot grade, so my thought was to roll the san tee
down a little bit so that the 1-1/2" vent would have the correct grade. Or should I use a 1-1/2" x 2" x 2"
wye fitting instead? It doesn't seem like it would make any difference for "air", and if there was a little
rain that got into the roof vent, wouldn't that moisture travel down a san tee just as easily as a wye?
I need to get "supplies" in the next day or two, so either way is just as easy. Just like to know what is
"correct".
Eventually, the 2" line will merge into a 3" roof vent. I've been told to make sure not to merge too
many DFU into a 2" line, but rather directly into the 3" line. I think the 1-1/2" kitchen sink and
DW vent are okay into the 2" bath vent though.
Kind regards!
Gregg G.