Town of Islip, New York Building Permit Guide

The Building Division of the Department of Planning and Development administers building and plumbing permit applications in the Town of Islip, reviewing them for compliance with the New York State Uniform Code and the Town of Islip Zoning Code. It is at One Manitton Court, Islip, NY 11751, with office hours M-F 8:00am-4:00pm.

This guide covers the Islip Building Division, its residential fee schedule, plumber licensing and the Town offices for zoning, engineering, fire prevention and right-of-way work. The Building Division page does not show e-mail addresses, so use the phone numbers below.

What requires a building permit in the Town of Islip?

Islip’s residential fee schedule covers new dwellings, additions and alterations, decks, accessory structures, pools, spas and hot tubs, solar panels, generators, demolition and plumbing and HVAC work. A generator needs a separate plumbing permit for any gas piping.

Residential work completed 4+ years ago without permits is handled with a compliance permit, valid for 1 year. Work done without a permit less than 4 years ago is charged a multiple of the current permit fee.

New York builds on one statewide code, the Uniform Code, outside New York City; the 2025 edition and 2025 Energy Code took effect on 31 December 2025 (the all-electric provisions remain suspended by court order). Cities, towns and villages administer it, and local standards stricter than the code need Code Council approval. The Uniform Code in New York

Who handles permitting in the Town of Islip?

Other Town of Islip offices on the way to a permit

Zoning Board of Appeals

The Zoning Board of Appeals, (631) 224-5489, handles variance applications arising from building permit denials, accessory apartment applications, two-family family-use-only (“Mother Daughter”) applications and special exceptions.

Subdivisions, site plans and land clearing

Questions on the Subdivision and Land Development Regulations go to the Engineering Division at 631-224-5360.

Work in the Town right of way

Repairs or new construction in the Town right of way need a Right of Way Work Permit from the Department of Public Works, and a copy must be on site. Department of Public Works: (631) 224-5610.

Fire Prevention

Fire Prevention sets its own inspection requirements; contact it at 631-224-5477.

Town of Islip permit costs and fees

From the Building Division’s residential schedule, effective May 1, 2024. Residential building permits are valid 1 year with 3 consecutive renewals unless noted.

The base fee is due when the application is accepted for intake, and square-footage fees before the permit is issued.

Plumbing licences and fees in the Town of Islip

Islip licenses its own plumbers: the Building Division issues master and limited restricted plumbing licenses, and the Town has a Plumbers Examining Board. Residential plumbing and HVAC fees are $160 plus $25 each for fixtures, $160 each for gas piping or a gas test, and $300 for the first ductless mini-split, split or heat pump system. Electrical inspections are done by a third party.

Where a municipality issues separate trade permits, the work is done under whatever electrical or plumbing licence that city, town or county requires; many places license neither trade. Trade licences in New York

How to get a building permit in the Town of Islip

Every permit carries an expiration date set by the Town of Islip, which may void a permit if work does not start in time; confirm the expiry on phased or delayed work. Permit validity in New York

Inspections in the Town of Islip

Call the Records Office at 631-224-5470 to schedule inspections, with at least 48 hours’ notice; the inspectors cannot schedule them, and an owner’s representative must be on site. Framing and rough-in work such as HVAC, plumbing and electric must pass their inspections, with electric inspected by a third party.

For all new buildings, house lifts and additions over 50% of the existing footprint, a foundation as-built survey signed and sealed by a NYS licensed surveyor (elevations referencing NAVD 88) and a design professional’s certification are needed before backfilling. Construction beyond the foundation cannot start until the Town accepts them.

Official Town of Islip permitting resources

These are the primary sources behind this guide. Codes, fee schedules and procedures change — confirm the position for your filing date.

• Town of Islip Building Division
• Islip residential fee schedule
• Islip inspection process, building and plumbing
• Islip Zoning Board of Appeals
• Islip Department of Public Works

Frequently asked questions

Can I file an Islip building permit on paper?

Applications must be filed electronically, following the Town’s Electronic Submittal Process flyer. Paperwork can be left in the Drop-Off Pail by the Building Division entrance.

Who schedules inspections in Islip?

The Records Office, at 631-224-5470, with at least 48 hours’ notice. The inspectors cannot schedule them.

What does a deck permit cost in Islip?

Under the May 1, 2024 schedule, $160 plus .37/sf for a deck 30 inches or under in height, and $220 plus .37/sf for one over 30 inches.

Simplify Town of Islip permitting with Alliance Permitting

• Confirm the Town office for the parcel and the zoning, highway or fire approvals that go with the permit
• Prepare the application, surveys and plans and file them through the Town’s portal or counter
• Schedule the Town’s inspections and follow the permit through to the certificate of occupancy

Alliance Permitting is a permit documentation and submission company in New York. We prepare your paperwork, file it correctly and coordinate with the permitting authority through issuance. We are not a contractor and we do not perform licensed plan review or inspections; that work stays with your licensed team and the jurisdiction.

This guide is provided by Alliance Permitting for general information about Town of Islip permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.