I also failed SPD awhile back. When I retook it, I added Ballast and also Building Construction Illustrated into my study material mix.
I don't recall getting questions on Cx (Building Commisioning). But 12...wow.
I found this link that may be helpful to you:
https://www.gsa.gov/graphics/pbs/BCG_3_ ... 34K-pR.pdfHOWEVER, by looking at the reference material provided by NCARB for the SPD exam, you will find information about Cx in "Mechanical & Electrical Equipment for Buildings" by Walter T. Grondzik, Alison G. Kwok, Ben Stein and John S. Reynolds
https://www.amazon.com/Mechanical-Elect ... 0470195657That is literally where they would most likely pull questions on the exam.
Hope this helps.
I know it's frustrating....you go in knowing so much information and then the exam ends up being on completely new material.....i feel ya......