For basement de-conversions the owner (if owner-occupied) may fill out a Certificate of Responsibility to remove partitions as well as an Easy Permit Application. If the property is not owner-occupied, then one needs a signed contract from a General Contractor. Also, a plumber’s letter of intent is needed (for cap and seal kitchen) as well as an electrical permit (applied for online) to remove any electrical components in the walls before they are taken down. One may keep the basement bathroom depending on how a particular violation is written. If the violation states "remove all partitions", then the bathroom must be removed as well. However, Plumbing fixtures may be kept for a washing machine.
For Attic de-conversions, the Dept. of Buildings requires a licensed architect to draw up plans and go through Standard Plan Review.