Final answer:
The maximum horizontal length for a required 2-inch vent pipe varies based on local codes, such as the UPC or IRC. It is essential to refer to these specific regulations or consult with a plumbing expert to determine the exact measurement in any given area.
Step-by-step explanation:
The question asks for the maximum horizontal length for a 2-inch vent pipe. In the context of plumbing, this refers to the venting system that helps protect trap seals in drainage systems by balancing the air pressure within the pipes. The answer to this question may vary based on local building codes and regulations. Generally, the Universal Plumbing Code (UPC) or International Residential Code (IRC) would have specific measurements for these limitations.
For instance, the IRC specifies that a vent can be as long as needed, provided that the developed length of the vent is within the limits established by the code, and there are proper supports. However, certain distances like a 1/4 inch per foot grade for drainage should be maintained, and the vent system must remain within the building's pressure zone to function correctly. To find the exact maximum length, you should check the specific code applicable in your area or consult a local plumbing expert. Without a specific context, giving an accurate measurement is not possible.