(a) Where there is a metering device inside the building or structure to which the water is being delivered for use, "plumbing" shall begin at the outlet or house side of the metering device which is closest to the inside face of the outermost foundation wall of that building or structure; and
(b) Where there is no metering device inside the building or structure to which the water is being delivered for use, "plumbing" shall begin at the outlet or "house" side of the main control valve which is closest to the inside face of the outermost foundation wall of that building or structure.
2. The Installation of Drainage Systems
The installation of drainage systems, storm and sanitary, presents different issues: There are very specific plumbing code provisions, particularly with large capacity rood drains, that must be satisfied. For this reason, the Board of State Examiners of Plumbers and Gas Fitters has interpreted the definition of plumbing as it exists in M.G.L., Chapter 142, Section 1, to include all building drains beginning from a point ten (10) feet from the inside face of the foundation wall and running into the building structure.
The reason that the Board has determined that all drains within the above area fall within the definition of "plumbing" is that this drain piping needs to be installed by licensed plumbers due to code requirements regarding cleanouts and location of cleanouts on drainage systems that exist inside the foundation wall. Drainage system cleanouts are frequently located close to the inside foundation wall on the section of the drainage piping that runs to ten (10) feet out from the inside face of the foundation wall. The ten (10) foot measurement is based on the standard length of cast iron soil pipe. That ten (10) foot length of pipe is typically installed at the end of a drainage system, and runs to ten (10) feet from the inside face of the foundation wall. Also, under revisions to the plumbing code to be implemented at the end of 2007, cleanouts can be installed on the drainage piping immediately outside the foundation wall.
In addition, drainage systems running to dedicated systems (rain water retention systems or gray water recovery systems, for example) are within the definition of plumbing, and must be installed by licensed plumbers.
For any storm or sanitary drainage pipe that runs through or under the footprint of a building or structure to a point ten (10) feet out from the inside face of the foundation wall shall comply with 248 CMR and be installed by licensed plumbers.
Pipes receiving discharge from exterior downspouts or gutters not entering the building or structure are not included with the definition of plumbing, and may be installed by unlicensed personnel.
Finally, perimeter, sub-soil or French drains that are installed within or outside the building or structure but do not discharge, communicate or convey discharge to the storm or sanitary drainage systems may be installed by unlicensed personnel.