I know this has been covered before, but I just received the following
comment from a GBCI reviewer for a v3 Core and Shell project I'm working
on. The project is basically an existing 5-story warehouse with almost
no windows. Part of the renovation is adding windows. The comment is
as follows:

Table 1.4.1B indicates that the window-to-gross-wall ratio is identical
in both cases; however it is unclear whether any fenestration was added
or removed as part of the renovation. The baseline ratio must reflect
the ratio as it existed prior to the renovation and the proposed ratio
must reflect the ratio as it exists after the renovation. Revise the
Baseline and/or Proposed cases as necessary so that the
window-to-gross-wall ratio is accurately modeled and provide a revised
prerequisite form and updated energy model output summaries as
necessary.

I didn't think that this was the case - I thought that if you had an
existing building, any EXISTING-TO-REMAIN windows would show up as the
existing window type, but any NEW windows in the proposed alteration
would be matched in the baseline model and comply with the Table 5.5
requirements. Meaning the WWR remained the 1:1 as long as it was < 40%
glass.

I think this is just a matter of educating the reviewer on our building,
but I wanted to make sure that there hadn't been a shift in how GBCI
reviews existing buildings.

Thanks!

James Hansen, P.E., LEED AP