Commissioning on Multi-Family Building (Residential)

I do not have direct experience in this area, but the use of random sampling is an accepted method of commissioning. The more “packaged” the systems, the more conducive to sampling it is, especially if the installation has limited impact on performance. However, we have had some systems that required significant adjustment to ensure performance (such as lighting controls), and recommend 100% testing on those systems. We have also see some equipment have more “out of the box” failures, so at a minimum make sure they heat, cool, and turn on, and we do that for all units. Then more complete testing is done on a sampling of units. Another example would be something like an air handling unit, which can require significant programming and should have testing on 100% of the units.