Interior / Garage Conversion ADU
$90,000 – $175,000+
Building condition, coastal materials specification, utility separation.
ADU Contractor in Narragansett, RI — Coastal South County Design-Build
Full-Service Design-Build · Serving Narragansett & Washington County · RI Reg. GC-40846
Written by Kenneth Trinque, RI Registered General Contractor (GC-40846) and Rhode Island Real Estate Broker.
Narragansett is one of Rhode Island's most distinctive residential communities — a coastal town known for its beaches, its Victorian-era summer cottage architecture, and an increasingly year-round population that has discovered something earlier generations knew: Narragansett is an exceptional place to actually live. For Narragansett homeowners, ADUs represent a particularly interesting opportunity: rental income from a well-designed unit in a coastal community is real, multigenerational living close to the water is genuinely desirable, and property values in South County support the long-term investment case.
Bluestone Homes is a full-service design-build contractor serving Narragansett and Washington County. We handle feasibility, design, permitting with the Narragansett Building Department, and construction — one team, from first conversation to final walkthrough.
Find out what your Narragansett property can do. → Book a Free Consultation
What Narragansett Homeowners Are Building
- Interior and garage conversion ADUs — Narragansett's residential lots — many dating to the early 20th century and sized for a different era's housing patterns — make within-footprint conversions (existing garage, ground-floor rooms, or basement space) the most practical ADU route in much of the town.
- Detached ADUs — for Narragansett properties that meet the 20,000 sq ft threshold, freestanding ADU construction by right under state law. Less common in Narragansett's denser beach neighbourhoods but available on larger parcels in the town's interior.
- Attached ADUs — additions tied to the primary home with their own entrance — designed to respect the architectural character of Narragansett's coastal residential neighbourhoods.
- Home additions — room additions and whole-home expansions on Narragansett's established housing stock, designed to integrate with existing rooflines and coastal architectural styles.
- Major renovations — large-scope interior renovations and whole-home updates on Narragansett's older coastal homes.
ADU Zoning in Narragansett, RI — What You Need to Know
Narragansett's zoning ordinance reflects the town's coastal character — residential districts include the beach neighbourhood zones closer to the shoreline and larger-lot residential zones in the interior. Rhode Island's 2024 ADU legislation provides by-right eligibility that applies across all residential zones, and Narragansett updated its code to comply.
Rhode Island State Law
Rhode Island General Laws §45-24-73 (amended June 2024) establishes by-right ADU eligibility statewide. Under this law, one ADU per lot is permitted by right where: (1) the lot is 20,000 square feet or more and the primary use is residential; (2) the ADU fits within the existing footprint of the primary structure or an existing accessory structure without expanding that footprint; or (3) the ADU is a reasonable accommodation for a family member with a disability. State law sets maximum ADU sizes at 900 sq ft (or 60% of the principal dwelling's floor area, whichever is less) for a studio or one-bedroom unit, and 1,200 sq ft for a two-bedroom unit subject to the same 60% cap. Rhode Island's ADU legislation prohibits all ADUs from being used as short-term rentals — they must serve long-term tenancy or household members.
Narragansett-Specific Requirements
Permits are filed with the Narragansett Building Department (25 Fifth Avenue, 401-789-1044, ext. 1302). Narragansett properties in coastal flood zones or within CRMC (Coastal Resources Management Council) jurisdiction may have additional elevation, setback, or environmental review requirements that affect ADU siting. These are assessed during the initial feasibility review.
Narragansett's historical overlay and beach neighbourhood zoning may impose additional design character requirements for exterior modifications in certain areas. Bluestone evaluates these constraints at the feasibility stage so the project plan is accurate from the start.
Why Narragansett Homeowners Choose Bluestone Homes
Narragansett's coastal regulatory environment — flood zones, CRMC requirements, and the town's attention to coastal character — is exactly the kind of project environment where having one design-build team managing everything is most valuable. When the team that assesses your coastal property constraints is the same one designing around them and building within them, you avoid the expensive translation problems that occur between separate firms.
- 40+ years of combined construction experience across Rhode Island and Massachusetts.
- Registered in Rhode Island — GC-40846. Licensed in Massachusetts — CS-121543. All work permitted, inspected, and built to code.
- Feasibility first — we evaluate your specific lot, zoning district, utility access, and site conditions before you invest in design. No surprises.
- One accountable team — the same people who assessed your property design it, permit it, and build it. No handoffs between separate firms.
- Transparent, line-by-line pricing — you review every line of the construction contract before you sign it. Budget shapes the design from day one.
ADU Planning Range — Narragansett, RI
These ranges give you a realistic planning framework before committing to design. Every project is different — lot conditions, ADU type, and finish level all affect the final number.
Attached ADU (addition)
$160,000 – $295,000+
Coastal context, setback clearance, roofline integration.
Detached ADU (~500 SF)
$165,000 – $250,000+
Lot threshold met, coastal considerations, site conditions.
Preliminary planning ranges. Coastal properties and those in flood zones may carry additional costs. Use the Bluestone Calculator for a first estimate.
Frequently Asked Questions — ADU in Narragansett, RI
Serving Narragansett and Surrounding Communities
Bluestone Homes serves homeowners throughout Narragansett — from the Point Judith peninsula and the beach neighbourhoods of Scarborough and Sand Hill Cove to the larger residential areas around Narragansett Pier — and the surrounding South County communities of North Kingstown, South Kingstown, and Westerly.