In looking to achieve this credit, I am planning on writing a Cx plan that meets the requirements described in the Reference Guide, but I am planning on putting the frequency of each inspection right at 2 years and doing them all at the same time, rather than spread them all out. This would be both cost effective for the client and make it easier for the CxA.
However, in reading the Reference Guide it seems that LEED is assuming all these inspections required will be done at different times. So the CxA would have to make multiple site visits throughout the year to perform each task, why not do it all at once? Would LEED frown upon this approach and would it still meet the intent of the credit?
Thanks!
Pierce Holstrom
Director of EngineeringEnvironmental Building Strategies
69 thumbs up
November 8, 2010 - 5:34 pm
Ben,
A lot of the ongoing commissioning items typically feed into a buildings normal operating plan. Checking calibration of thermostats, confirming supply temperatures, confirming functionality of lighting controls... Are the retro-commissioning items you are referring to similar to an outside air balance or another larger maintenance service?
Maria Unruh
Electrical EngineerAntella Consulting Engineers
72 thumbs up
November 8, 2010 - 6:11 pm
Well I am certainly referring to all of those items you listed, as well as bigger picture items such inspection of HVAC equipment, pumps, fans, filters, motors etc. The items you listed are certainly included in my list but from what I understand the intent of the credit is for a 3rd party to complete the tasks, not the building maintenance staff. So why have a CxA come to the site to simply confirm supply temps, wait three months then come back and confirm functionality of lighting controls? The fact that LEED wants 50% completed during the performance period is confusing, wouldn't it be logical just to it all at one time?
Pierce Holstrom
Director of EngineeringEnvironmental Building Strategies
69 thumbs up
November 8, 2010 - 7:44 pm
I'm not sure a 3rd party is required for this credit. It does ask that the commissioning team take a systems wide approach that is beyond the normal operation and maintenance scope. If the operations staff contracts with a 3rd party to perform a detailed functional testing every 2 years it will certainly add great value by helping to calibrate the ongoing commissioning testing that is being performed as part of the operating plan. It should be noted that the ongoing functional testing piece of the commissioning process can be automated through a buildings BMS system. Check out this article for a case study: http://resources.cacx.org/library/holdings/050.pdf.