Bull Head Tee on vent pipe

[Ken Amelin]

I know that a bull head tee connection is not "Best practice", but is there any code reference that confirms this?

Thanks.

[John Dirks Jr]

I'm not sure about the specific code reference you are asking about but the vent pipe should have an upward slope toward the chimney. 1/4 inch per foot minimum. That one looks level at best, or maybe even slightly down sloped toward the chimney.

[John Dirks Jr]

Here's some good venting information. The 1/4 inch per foot requirement is mentioned at this page.

Guide To Flue Vent Connectors - Heating Boilers, Furnaces, Water Heaters & Chimney Flues (http://www.inspectapedia.com/chimneys/Flue_Vent_Connectors.htm)

[A.D. Miller]

G2427.10.8 (503.10.8) Slope. A vent connector shall be
installed without dips or sags and shall slope upward toward
the vent or chimney at least 1/4 inch per foot (21 mm/m).

Exception: Vent connectors attached to a mechanical draft
system installed in accordance with the manufacturers’
instructions.

The ideal chimney or vent configuration is a totally vertical
system, even though it is not always practical.
This section requires all portions of a chimney or vent
connector to rise vertically a minimum of a 1/4 inch per
each foot (21 mm/m) of its horizontal length. The connector
slope is intended to induce the flow of flue
gases using the natural buoyancy of the hot gases.
Connector slope can promote the priming of a cold
venting system and can partially compensate for short
connector vertical rise. Low points, dips and sags
could also trap condensate and accelerate corrosion
of the connector. The exception allows connectors
without slope where connected to mechanical draft
systems because the connector is on the negative
pressure (inlet) side of the exhauster and slope would
provide no benefit.