Sandpoint planning commission workshop weighs switching to impervious-surface standard to enable small‑lot infill

Sandpoint — City planning staff on Tuesday proposed rewriting lot‑coverage rules to encourage small‑lot infill and modest increases in multifamily capacity, presenting a draft that would replace a separate maximum building‑footprint limit with a single impervious‑surface standard that scales down as lot size increases.

"The gist of it is we were proposing eliminating the max building footprint standard and going to a single impervious surface standard of 70% in residential single family and residential multifamily," said Jason Welker, Community Planning and Development Director, summarizing the staff proposal and earlier public hearings.

Staff said the change is intended to make it easier for property owners on small historic lots to build additions or accessory dwelling units (ADUs) without changing setbacks, while preserving neighborhood scale on the town’s larger lots. Welker told the commission a third‑party GIS analysis to map lot sizes was cost‑prohibitive, so staff used in‑house tools and flagged the numbers as approximate.

Why it matters: Sandpoint’s existing 35% building‑footprint cap can prevent common housing types on many small lots. Welker cited examples showing how a switch to an impervious‑surface standard could let homeowners add living space or fit an ADU where the current footprint limit blocks them, supporting comprehensive‑plan goals for diverse lot sizes and infill.

Key details and debate - Scale and mechanics: Staff proposed a table that lowers allowable impervious‑surface percentages as lot size increases (illustrative top‑line percentages discussed ranged from about 70% down toward 35% on the largest city lots). Commissioners raised practical concerns that the stepwise table could produce anomalies where a slightly larger lot is allowed a smaller building than a slightly smaller lot. Several commissioners asked staff to convert the table into a smoother formula or curve so allowable buildable area increases monotonically with lot size.

- Density and units: The proposal for RS (single‑family) zones primarily aims to enable ADUs on small lots. Welker also introduced a related change for the RM (multifamily) zone that would slightly raise structure size and, in some cases, allow an additional unit — what staff described informally as "another doorknob." Commissioners discussed whether such unit increases should rely on lot size, road frontage or both.

- Frontage and flag lots: Several commissioners noted that a frontage‑based standard can block multifamily development on deep lots with limited street frontage. Staff said possible fixes include administrative exemptions or case‑by‑case review; they flagged the need to refine frontage rules before drafting an ordinance.

- Parking and other limits: The commission discussed parking as a practical constraint. Staff summarized current rules: apartments/duplexes/townhomes under 1,200 sq. ft. require one parking space per unit; detached single‑family units with more than three bedrooms require two spaces. Welker said parking requirements and setbacks will continue to limit how much additional dwelling capacity can be realized in practice.

- Snow storage and site review: Commissioners asked where on‑site snow will be stored as unit counts rise. Staff said site‑plan review requires snow storage for projects with four or more units but noted the zoning code contains no quantitative snow‑storage standard for smaller projects.

Public comment and local concerns During the public‑comment period, John Plute urged the commission to consider parking when approving denser housing. "All I'm saying is, please, when you're considering these, remember that a housing unit generates 2 cars on average," Plute said, pointing to a proposed 11‑unit project that he said lacks visible parking provisions.

Next steps and timeline Staff said they will refine the lot‑size curve into a simpler, administrable formula, take a deeper look at frontage thresholds and parking implications, and return with a draft ordinance for a public hearing. Welker tied the proposal to comprehensive‑plan objectives to "identify and resolve barriers to impede the development of workforce housing" and to encourage compact infill.

Votes at a glance - Consent calendar: Approved by voice vote after a motion by Commissioner Wayne Benner and a second by Commissioner Grant Simmons; the transcript records a voice vote ('Aye') but does not record individual roll‑call tallies.

What’s next: Staff told the commission the next meeting will include three public hearings (a short‑term rental code amendment, a subdivision and a conditional‑use permit) and said the revised lot‑coverage language will be brought back for public hearing once the curve and frontage issues are clarified.