Planning a home renovation in the Town of Islip

What this page covers

This page is about interior renovation planning for single-family and two-family houses in the Town of Islip: kitchens, bathrooms, finished rooms and whole-floor updates. Structural alterations, additions and new construction are not current planned services. Project availability and service-area approval have not been established.

Town, village or shared hamlet

Which hamlet, and which jurisdiction?

The Town of Islip's own list names 17 hamlets: Bay Shore, Bayport, Bohemia, Brentwood, Central Islip, East Islip, Great River, Hauppauge, Holbrook, Holtsville, Islip, Islip Terrace, Oakdale, Ronkonkoma, Sayville, West Sayville and West Islip. It marks Hauppauge, Holbrook, Holtsville and Ronkonkoma as only partly located in Islip.

A town plan hosted by the New York State Department of Environmental Conservation names the other towns involved: Hauppauge is shared with Smithtown; Holbrook, Holtsville and Ronkonkoma with Brookhaven; and Lake Ronkonkoma with Brookhaven and Smithtown. The same plan lists four incorporated villages, Brightwaters, Islandia, Ocean Beach and Saltaire, and says land use in those villages is controlled by their own zoning ordinances, while the town controls land use and zoning in the unincorporated areas.

Sort the scope first

Does your plan raise a zoning question, or only a building-code one?

The town's Building Division administers building and plumbing permit applications and reviews them for compliance with the New York State Uniform Code, the Town of Islip Zoning Code and the town's subdivision and land development regulations. Zoning rules are in Chapter 68 of the Code of the Town of Islip. A separate Zoning Board of Appeals handles variances, accessory apartments and two-family "mother/daughter" special exemptions.

For planning, that suggests sorting your wish list before any estimate. Replacing finishes, cabinets or fixtures in the same layout is one kind of question. Adding a second kitchen, creating space for a relative or a tenant, or anything that changes the outside of the house is another, because it may involve zoning and the board, not only a building permit. Which applies to your house is for the town and a qualified professional to say.

The town also publishes a zoning FAQ, dated April 2021, that explains how a homeowner can check a property's zoning classification and how a variance request goes to the Zoning Board of Appeals after a denial. The FAQ describes itself as general guidance, not legal advice, and it is several years old; check current town information before relying on any specific rule in it.

Before you schedule work

Timing: the December 2025 code update and electronic filing

Permit applications in the town are filed electronically, and the town's building permit types include an 'Interior Arrangement' type (the buildout of a shell building). The town has given notice that the updated New York State Uniform Code and State Energy Code take effect on December 31, 2025. Its notice says applications not accepted for intake with the fee paid before that date are reviewed under the updated rules.

If a design was drawn some time ago, ask the designer whether it was prepared for the code that now applies. The town publishes requirement sheets for particular kinds of residential work; one published sheet covers foundation-only work and lists items such as signed and sealed plans and a recent survey. That list is specific to foundation work. Ask the Building Division which requirements, if any, apply to your scope instead of assuming one sheet covers every project.

Zoning and flood information

Use the town map before the walkthrough

The town's Planning and Development department points to the Town of Islip Map Viewer for zoning and FEMA flood-zone information. Looking up the address before a site visit gives a starting point for questions about the zoning district and whether a flood zone affects ground-floor or basement work. A map result is not a determination; flood-zone implications for a particular renovation need professional review.

For the wider Suffolk picture, see the Suffolk County page and the permits guide. For older houses, the older-home guide lists the checks to make before walls are opened.

Then write a brief that can be priced consistently

• The exact address, the hamlet name, and the jurisdiction once confirmed (town or village)
• Each room in the plan, marked keep, replace or investigate, as in the whole-home guide
• Which items you sorted as possible zoning questions, and the answer you got
• Who lives in the house during the work, and which rooms must stay usable
• Selections still undecided, with an allowance noted for each, so proposals can be compared like for like

Scope examples are on the kitchen remodeling, bathroom remodeling and whole-home renovation pages. The estimate comparison guide explains what to line up across proposals.