Alteration Type 1 Application

Used when you need to change the occupancy of a building that's designated on the existing Certificate of Occupancy
or if there is no Certificate of Occupancy present.

Typically takes 3-4 months to process in the DOB.
Costs roughly twice as much as an Alteration Type 2 Application (About $5,500)

Paperwork included in this application:
EF1 Electronic Filing Cover Sheet
PW1 Plan Work Approval
PW1A - Occupancy / Use Schedule
PW1B - Plumbing / Sprinkler / Standpipe Schedule
PW3 - Cost Affadavit saying how much you're spending on the project. (DOB uses this info to figure out how much to charge you for the permit)
ASB-4 - Asbestos Forms (You will need to get an asbestos inspection for any work in NYC)
ST1 - Street Tree Checklist (Shows compliance with or exemption from street tree zoning requirements)
PW4 - Mechanical Use Permit (This is coordinated with the mechanical engineer)

All of these forms are found here

The DOB won't close out an Alt 1 until all construction, electrical, fire alarm, elevator, sprinkler, structural, mechanical and plumbing permits have been closed out.
This presentation explains the exceptions to that rule.