Split certification doubts

I can't imagine NOT doing a split review, but to each their own.  I do usually submit the design review after the construction documents are done, though.  Some projects submit for design review before CDs are done, but I have not been successful in hitting that timeline yet.

1. You do NOT have to submit all your design credits during the design review; only design credits can be submitted during design review but both design and construction credits can be submitted during the construction review. 

2. If a design credit that has been reviewed during the design phase experiences changes during the construction of the building, the credit needs to be reopened and modified, and then submitted for review with the construction credits and any remaining design credits during the construction review.

I agree with Renee, and generally submit the design review right after CDs are done. There are so many benefits to doing a split review. It is my preferred way of managing the LEED process.

In my experience, design review credits tend to be a little more subjective and open to interpretation. Having them done before the construction review feels great and helps the team determine what, if anything, needs to change during the construction review. Maybe a different innovation credit needs to be pursued or another credit needs to be added to achieve the project's LEED certification goals. 

I echo Renee and Sara's comments about the advantages of a Split Review. In addition, it really helps the design team get the majority of their items done while the design is still fresh in their minds, which I think paramount to a successful project. (Many designers hand off Construction Administration responsibilities to other team members, and you can lose the designer's perspective on why something was designed the way it was.)

For a little history, reviews have gone back and forth between Split vs. Combined over the years. LEED Online v2 was set up with a "Design Submittal" followed by "Construction Submittal with Certification Award" as the default timeline. Teams had the choice to combine the two reviews into one - "Design and Construction Submittal with Certification Award." USGBC changed LEED Online v3 to make a combined application the "Standard Review" so I can imagine many teams just took this approach as the way to go (maybe not even knowing about the Split Review option). And another motivation for a Combined timeline may be that there is slight certification fee cost as compared to the Split timeline - https://new.usgbc.org/cert-guide/fees. 

And thanks to this post, I was able to find where USGBC defined when the Design Submittal was supposed to be submitted (at least under LEED Online v2). LEED Online v2 stated: "Credits marked as "Design" may be submitted and reviewed at the end of the design phase, defined as 100% Construction Documents." I've never understood how teams could possibly submit the Design Submittal prior to the completion of the CDs as the design work was not complete.