Smithtown homeowners ask us a version of the same question every week: "Huntington gets the $125K grant — does a garage conversion still make sense on my side of the line?" Short answer: yes, and the town's own code is the reason. The Town of Smithtown — including Nesconset, St. James, Kings Park, and the Smithtown side of Commack — permits accessory apartments for owner-occupied homes, and the rental market does the rest of the work the grant would have done.
What Smithtown Allows
- Owner-occupied properties can add one accessory apartment, subject to the town's size limits and approval process.
- Full code conversion — insulation, ceiling height, egress, its own kitchen and bath, smoke/CO protection, and parking that replaces the garage spaces you're converting.
- Certificate of occupancy after final inspections — the document that makes the unit legal to rent and countable at appraisal.
We prepare the drawings, file with the town, and carry the project through inspections. Construction runs 8–12 weeks for a typical attached-garage conversion once approvals are in hand.
The Math Without the Grant
A Smithtown garage conversion — one bedroom, full bath, kitchenette, mini-split HVAC — typically costs $50,000–$100,000. Accessory apartments in the Smithtown–St. James corridor rent for roughly $1,600–$2,200/month, or $19,000–$26,000 a year. That's a 4–6 year payback on rental income alone, before counting the 15–35% the legal unit adds to appraised value — or the assisted-living bills it replaces if the "tenant" is Mom or Dad. That comparison, in real numbers.
Watching the Grant Map
New York's Plus One ADU Program expands in funding rounds, and participating towns have changed between rounds. Smithtown isn't on the list today — but if it joins, existing plans and an approved unit put you at the front of the line. If grant money is the deciding factor for you, tell us during the walkthrough: we track the program's rounds because our Huntington-side clients use it constantly, and we'll flag you the moment eligibility changes.
Program status — verified September 2026
Plus One ADU is a New York State program (an $85 million allocation through the Housing Trust Fund Corporation) but it is run town by town, and each town's intake opens and closes on its own schedule. As of September 2026 on Long Island: Huntington and Riverhead are accepting applications; Brookhaven, Islip and Southold are closed. Babylon, East Hampton, Shelter Island and Southampton run their programs through Community Development Long Island rather than the Long Island Housing Partnership.
The $125,000 is a cap, not an amount every applicant receives, and it is awarded as a grant. Huntington's published guidelines cap household income at 100% of Nassau/Suffolk area median income (2023 HUD limits: $109,400 for a one-person household, $156,300 for four) and require that you have owned and lived in the home for at least one year. Applications go on a first-come waitlist and are then re-ranked on priority points, including whether the unit will be affordable at or below 80% AMI and whether it can be permitted without a zoning variance. Municipal code always overrides the program guidelines. Verify your town's status before you budget around a grant: LIHP (631) 435-4710. We also check it for you on the walkthrough — see our Plus One ADU grant page for the eligibility checklist and what the build costs if your town's round is closed.
Thinking about your garage?
Free walkthrough — we'll tell you if it qualifies and what it would cost. No pressure.
Get a Free Estimate
Tell us about your project — we respond within 24 hours.
No spam. No obligation.
Frequently Asked Questions
Are accessory apartments legal in Smithtown?+
Does Smithtown participate in the $125K Plus One ADU grant?+
What does a garage conversion cost in Smithtown?+
How long until a Smithtown conversion pays for itself?+
Related Articles
Work With Alec's Construction
This guide is written by the crew that does the work. See Alec's ADUs service — accessory apartments, garage conversions and grant paperwork. Licensed and insured on Long Island, one crew start to finish, free walkthrough and a written estimate inside 48 hours.
Booking the cold months now: we also handle Additions & New Construction and Bathroom Remodeling.
Every town here has villages inside it running their own building department. Our directory sorts out which counter your address actually files at.
Also Serving Smithtown
- ADUs in Smithtown — accessory apartments and grants
- Basement Finishing in Smithtown — egress, ceiling height and moisture
- Bathroom Remodeling in Smithtown — full gut renovations
- Chimney Repair in Smithtown — repointing, crowns, caps and flashing
- Deck Builders in Smithtown — new builds, repairs and railings
- Driveway Paving in Smithtown — blacktop, resurfacing and repairs
- Emergency Roof Repair in Smithtown — tarping, leaks and storm response
- Front Steps & Stoops in Smithtown — rebuilds, treads and railings
- Gutter Installation in Smithtown — seamless gutters, fascia and drainage
- House Painters in Smithtown — exteriors while the fall window holds
- Storm Damage & Insurance Restoration in Smithtown — emergency tarping and the claim
- Interior Painting in Smithtown — the right work for the cold months
- Kitchen Remodeling in Smithtown — cabinets, counters and layout
- Masonry & Pavers in Smithtown — patios, walkways and retaining walls
- Roofing in Smithtown — tear-offs, repairs and storm damage
- Siding in Smithtown — James Hardie, vinyl and cedar
Ready to See What Your Garage Could Become?
Free walkthrough anywhere on the North Shore. We'll check zoning, grant eligibility, and give you a real number — usually within 24 hours.
Get a Free Consultation