You don't even indicate how the project will be funded, but I presume the building--not individual owners--is footing the bill. Generally, this should be classified as a cap improvement by the building's auditors, who should share with owners every year a total of all such improvements. Each owner--depending on his/her tax situation--is generally entitled to multiply the total building expense by their % ownership & add to their basis, reducing taxes on the eventual sale of their unit.

Auditors & Boards often don't bother to do a thorough job of calculating & reporting capital expenses; some don't do it at all. Summary dismissal/recall seems appropriate in such instance.

Additionally, NYSERDA & other programs might allow/award extra tax credits for major energy-saving initiatives such as you describe; it's worth investigating.