Envelope CxA Requirements

An interpretation from 2016 gives guidance on this issue, look for ID10447. Besides defining the role of a Prime CxA. For those instances where fundamental and enhanced may be done by different firms with different contractual relationships. Toward the end of the ruling (which was not in the question by the way) it clarifies the envelope CxA. It is not too long, so here you go.

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For projects pursuing Option 2, envelope commissioning, the building envelope commissioning agent (BeCxA) may be completely independent of the lead CxA, and oversight of envelope commissioning activities by the lead CxA is not required. However, in this case, the BeCxA must meet all credit requirements for the Commissioning authority. Specifically:

• The BeCxA must have documented envelope commissioning process experience on at least two building projects with a similar scope of work.

• The BeCxA may be a qualified employee of the owner, an independent consultant, or a disinterested subcontractor of the design team.
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Now your question. The scope of an envelope consultant, in my experience, varies significantly. If the role is truly consulting, ie no content or design development, then I think you could have them be the BeCxA. This is similar to previous rulings where a LEED Consultant can be the CxA. However, if the role is more design related, producing details, drawings, specifications, etc., then I do not think they can act as a disinterested party.