Install a window or through-wall AC unit
New York City · checked on November 6, 2026
Not fully confirmed. The city's own pages do not settle all of this answer:
- Whether cutting a new sleeve opening in an outside wall that is neither load-bearing nor fire-rated needs a permit is not stated.
- Whether installing a window or through-wall unit needs DCWP's home improvement license is not stated.
Permit needed?
It depends on the job
It turns on what the job is:
- Where does it go: Existing window or existing wall sleeve; How big is the unit: 3 tons (36,000 BTU/hr) or less: No permit.
- Where does it go: Existing window or existing wall sleeve; How big is the unit: Over 3 tons, up to 5 tons, in a 1- or 2-family house: No permit in an existing 1- or 2-family house.
- How big is the unit: Bigger: Permit needed.
- Where does it go: New hole cut in the wall: Cutting any part of a load-bearing or required fire-rated wall is not a minor alteration, so a permit is needed; for other walls no source decides it.
- Does it need a new electrical circuit: Yes: New wiring needs an electrical permit by a licensed master electrician.
Only when:
- Packaged unit (not a split system)
- Not part of an alteration that otherwise requires a permit
Confirm with the NYC Department of Buildings before you start.
The city's own words on the permit (5 quotes)
- “Packaged air-conditioning unit not exceeding 3 tons rated capacity, installed in an existing building, including installations in existing windows or in existing sleeves under windows, and that is not part of an alteration that otherwise requires a permit.” — 1 RCNY §101-14 Categories of work that may or may not require a permit (NYC Department of Buildings rule, PDF), page date: Rule effective 2011-10-02; latest amendment effective 2026-06-10 (per DOB promulgation details)
- “Packaged air-conditioning unit not exceeding 5 tons rated capacity, installed in an existing building, including installations in existing windows or in existing sleeves under windows, and that is not part of an alteration that otherwise requires a permit.” — 1 RCNY §101-14 Categories of work that may or may not require a permit (NYC Department of Buildings rule, PDF), page date: Rule effective 2011-10-02; latest amendment effective 2026-06-10 (per DOB promulgation details)
- “A work permit or equipment use permit is generally not required to install a common window AC unit, unless the unit exceeds three tons/36,000 BTU/hr.” — Installing Air Conditioning Units (DOB), no date on the page
- “1. The removal or cutting away of any load bearing or required fire rated wall, fire door, floor, or roof construction, or any portion thereof; 2. The removal, cutting, or modification of any beams or structural supports;” — NYC Administrative Code Title 28, Chapter 1 Administration (2022 NYC Construction Codes, as amended; DOB-hosted PDF), page date: Edition includes Local Law 128 of 2024 (effective 2025-12-21) and Local Law 142 of 2025 (effective 2026-02-24)
- “No installation and modification to any electrical systems can be performed without a permit and a Licensed Master Electrician.” — Project Requirements for Owner - Electrical Systems (DOB), no date on the page
License needed?
No DOB license named for setting a packaged unit in an existing window or sleeve; any new wiring by a licensed master electrician.
DCWP's home improvement contractor license: not confirmed.
Confirm with the NYC Department of Buildings for trade licenses, and NYC Department of Consumer and Worker Protection for the home improvement license.
The city's own words on the license (3 quotes)
- “Make sure the unit is installed securely. Support the unit from underneath, or firmly fasten it from inside with angles.” — Installing Air Conditioning Units (DOB), no date on the page
- “1. To perform electrical work unless such person is a licensed master electrician or working under the direct and continuing supervision of a licensed master electrician.” — NYC Administrative Code Title 28, Chapter 4 Licensing and Registration (DOB-hosted PDF), page date: Edition includes Local Law 128 of 2024 (effective 2025-12-21) and Local Law 142 of 2025
- “Central air or heating installation” — Home Improvement Contractor License (NYC311, official City portal), no date on the page
Sales tax on the invoice?
New York State's answer, from its tax department's pages. The sales tax rate, with any local share, was not checked here.
It depends on the kind of work, so here is each answer, side by side:
- Repairing a thing
- Taxed
- Repairing a home or building
- Taxed
- Installing
- Depends
- New build
- Not taxed · see the caveat
Installing: Installing something that becomes a permanent part of the building (water heater, kitchen cabinets) is a capital improvement and not taxable. Installing things that do not become part of the building (freestanding appliances, above-ground pools, canvas awnings, weather stripping) is taxable.
New build: The contractor pays sales tax on the materials.
Worth knowing: The certificate the customer gives for capital-improvement work (Form ST-124) is not quoted here.
Confirm with the New York State Department of Taxation and Finance. Every answer for New York: sales tax on labor in New York.
New York's own words on the tax (8 quotes)
- “Installing, maintaining, servicing, or repairing tangible personal property that is not held for sale by the purchaser of the service in the regular course of business (for example, servicing automobiles, repairing appliances, and repairing radio and television sets).” — Publication 750: A Guide to Sales Tax in New York State, page date: Pub 750 (11/15)
- “A contractor or subcontractor must charge sales tax to its customers if the work performed is repair, maintenance, or installation work.” — Tax Bulletin ST-129: Repair, Maintenance, and Installation Services to Real Property (NYS Dept. of Taxation and Finance), page date: Issue Date: March 17, 2016
- “For example, building a deck, installing a hot water heater, or installing kitchen cabinets are all capital improvement projects. Repairing a broken step, replacing a thermostat on a hot water heater, or painting existing cabinets are all examples of taxable repair and maintenance work.” — Tax Bulletin ST-104: Capital Improvements, page date: Issue Date: July 27, 2012
- “The service of installing items that do not become part of the real property is taxable. This includes the installation of items such as: freestanding appliances above-ground swimming pools canvas awnings weather stripping” — TB-ST-129 (installation of items that do not become real property), page date: Issue Date: March 17, 2016
- “Building materials and other tangible personal property purchased for capital improvement work are taxable, whether purchased by a contractor, subcontractor, repairman (hereafter contractor), or homeowner.” — TB-ST-104 (materials), page date: Issue Date: July 27, 2012
Paperwork
The official forms for this job:
The city's own pages give two answers
The dollar line for the home improvement license
- “Repairs costing more than $200” — Home Improvement Contractor License (NYC311, official City portal), no date on the page
- “Handyman work costing less than $250” — Home Improvement Contractor License (NYC311, official City portal), no date on the page
Which buildings the home improvement license covers
- “A person or business must have a Home Improvement Contractor license to do construction, repair, remodeling, or other home improvement work to any residential land or building in New York City.” — Home Improvement Contractor License Application Checklist (NYC DCWP), page date: not shown on page; linked checklist PDF dated 9/11/2026
- “Work performed in buildings with more than four units/apartments EXCEPTION: If a building has more than four units/apartments, a license is required for work contracted by an owner or tenant that is performed in the specific unit/apartment in which that person resides” — Home Improvement Contractor License (NYC311, official City portal), no date on the page
Where to take the waste
What this job leaves, the rules for a business, then places that take it from one. Call ahead before you go.
Appliances with refrigerant (window and through-wall AC, mini-splits, refrigerators, dehumidifiers) if an old unit is taken away
The rules for a business, in the official words, and every place that takes it.
Not for contractors: household-only routes, never a place to take a job's waste.
- DSNY SAFE Disposal Events: residents only, no businesses or commercial vehicles. “NOTE: These events are for NYC residents ONLY. NO businesses or commercial vehicles.” — SAFE Disposal Events — DSNY
- “Appointments made by a business may result in a Notice of Violation.” — CFC Removal — DSNY
- DSNY CFC/Freon removal appointment (curbside): households only (“Service is available for residents ONLY.”, CFC Removal — DSNY)
- SAFE Disposal Events: households only (“NOTE: We DO NOT accept plug-in appliances (microwaves, vacuum cleaners, box fans) or ones containing CFCs.”, SAFE Disposal Events — DSNY)
A place that takes it from a business:
The place
- Licensed scrap metal processors (see the metal list) · from a business: Depends (“The final person in the disposal chain (such as a scrap metal recycler or landfill owner) is responsible for ensuring that refrigerant is recovered from equipment before its final disposal.”) · source: Stationary Refrigeration Safe Disposal Requirements — US EPA · checked on: November 6, 2026 · Call ahead
Confirm with each place before you go: call ahead.
Sources
Every page quoted (13 pages)
- 1 RCNY §101-14 Categories of work that may or may not require a permit (NYC Department of Buildings rule, PDF) — page date: Rule effective 2011-10-02; latest amendment effective 2026-06-10 (per DOB promulgation details); checked on November 6, 2026
- Installing Air Conditioning Units (DOB) — no date on the page; checked on November 6, 2026
- NYC Administrative Code Title 28, Chapter 1 Administration (2022 NYC Construction Codes, as amended; DOB-hosted PDF) — page date: Edition includes Local Law 128 of 2024 (effective 2025-12-21) and Local Law 142 of 2025 (effective 2026-02-24); checked on November 6, 2026
- Project Requirements for Owner - Electrical Systems (DOB) — no date on the page; checked on November 6, 2026
- NYC Administrative Code Title 28, Chapter 4 Licensing and Registration (DOB-hosted PDF) — page date: Edition includes Local Law 128 of 2024 (effective 2025-12-21) and Local Law 142 of 2025; checked on November 6, 2026
- Home Improvement Contractor License (NYC311, official City portal) — no date on the page; checked on November 6, 2026
- Home Improvement Contractor License Application Checklist (NYC DCWP) — page date: not shown on page; linked checklist PDF dated 9/11/2026; checked on November 6, 2026
- SAFE Disposal Events — DSNY — no date on the page; checked on November 6, 2026
- CFC Removal — DSNY — no date on the page; checked on November 6, 2026
- Stationary Refrigeration Safe Disposal Requirements — US EPA — no date on the page; checked on November 6, 2026
- Publication 750: A Guide to Sales Tax in New York State — page date: Pub 750 (11/15); checked on November 6, 2026
- Tax Bulletin ST-129: Repair, Maintenance, and Installation Services to Real Property (NYS Dept. of Taxation and Finance) — page date: Issue Date: March 17, 2016; checked on November 6, 2026
- Tax Bulletin ST-104: Capital Improvements — page date: Issue Date: July 27, 2012; checked on November 6, 2026
This is a plain-words summary of official city and state pages as of November 6, 2026, not legal or tax advice. Rules change and have exceptions: confirm with the departments named on this card before you start or bill.