AmeriVent Type B gas vent uses a double wall of metal pipe for insulation and safety. The inner pipe of reflecting aluminum heats quickly, containing the warm flue gases inside. The airspace between the inner and the outer pipes provides insulation against heat loss to keep the warmer flue gases on the rise.

Is B vent single wall?

The single-walled portion of the vent is called a “connector” and is only allowed from the appliance to the B-vent. … Aside from the fact that the results look jackleg and the vents leaked, the result was loss of gas buoyancy and damage to the vent system.

What is double wall venting?

Type “B” double-wall vent pipe allows you to install it within 1 inch of combustible materials, such as wood framing and wall materials. The air space between the inner and outer walls of the vent’s double wall construction insulates the pipe, preventing the hot inner wall from coming in contact with combustibles.