Building‑code update preview: staff recommends aligning model codes, adjusting wind/snow references and adding exterior sheathing requirement

Gary, the city’s building official, reviewed proposed updates to Chapter 126 of the Marion municipal code and flagged several items for council attention prior to a public hearing and proposed ordinance on the Thursday agenda.

Key staff proposals include:

• Increase the threshold for accessory structures that do not require building permits from the locally applied 120 square feet to 200 square feet to match the International Residential Code (IRC).

• Update the referenced wind‑load value to 108 mph (to align with the current code indexing used by neighboring jurisdictions) and adjust the snow load reference from 30 to 36 where the model code prescribes the higher value.

• Require structural plywood or similar structural wood sheathing when builders choose to use rigid exterior foam sheathing to achieve required R‑values (staff identified concerns that foam alone does not reliably hold siding fasteners and could increase repair and enforcement needs after wind events). Gary noted staff will add a minimum sheathing thickness (7/16" was discussed) to the ordinance language.

• Remove locally redundant smoke‑alarm and sprinkler ordinance language that duplicates the International Residential Code; staff and the fire marshal support relying on the model code language instead of local repetition.

Gary said the construction code review board recommends the changes. He acknowledged potential builder concerns about cost for added structural sheathing and invited builders to give public comment at the hearing; staff emphasized the change aims to protect long‑term structural attachment of siding and reduce post‑storm enforcement and repair burdens.

What’s next: staff will present ordinance language and set a public hearing on Thursday; builders and stakeholders may testify during that hearing.