Is My Project an Alteration or New Construction?
It is the first question to settle, because it decides which requirements apply and how much has to be documented. And the answer is not always the obvious one — a first-time fit-out of a space that has never been occupied is treated as newly constructed, not as an alteration.
Why the category decides everything
New construction is assessed as a whole building against the full applicable requirements. An alteration is assessed only on what changes: the altered components and any new equipment serving them. An addition is assessed as new conditioned area.
The same physical work can therefore carry very different obligations depending on which bucket it lands in. Getting the category wrong is not a documentation error — it means the wrong requirements were applied from the start.
The first-time fit-out trap
A tenant improvement in a space that has never been occupied or used meets the definition of a newly constructed building, not an alteration. Shell-and-core buildings produce this constantly: the shell was permitted, the space has stood empty, and the first tenant's fit-out is new construction.
A fit-out in a previously occupied space is an alteration. The distinguishing fact is whether the space has ever been in use — not whether the building is new, and not whether anything is being torn out.
Changing the occupancy classification
Where an alteration changes the occupancy classification, the alteration requirements apply to the new occupancy type rather than the old one. Converting retail to medical office means the medical office requirements govern, even though the building's history is retail.
This is how a project that looks like a light refresh becomes a substantial compliance exercise: the new occupancy may carry ventilation and lighting expectations the existing building was never built to.
Newly conditioned area is a third case
Bringing previously unconditioned space into conditioned use is newly conditioned floor area, and it is treated as an addition rather than as an alteration — regardless of whether anything is built. A change of use that also conditions a former storage bay is doing two things at once and needs to be scoped as both.
Alterations are assessed on what changed
Once a project is genuinely an alteration, the scope is bounded by the work. Prescriptively, the altered components and new equipment serving them meet the applicable requirements. On the performance path the compliance software takes the standard design for each altered component from a table, which is the mechanism that lets a shortfall in one place be traded against a gain elsewhere.
That trading mechanism only exists for alterations, and it is a substantial reason the category matters commercially rather than only technically.
Four questions that settle it
Has this space ever been occupied or used? Is any floor area being newly conditioned? Is the occupancy classification changing? And is existing-building work in the same permit as new work? Answer those four and the category, the requirements and the documentation all follow.