Shoreline, WA Rental Property Rules: Repairs & Habitability (2026)

Shoreline's rental habitability heating standard comes from IPMC Sections 602.2 and 602.3, adopted through SMC § 15.05.070. Section 602.2 requires every residential occupancy, rented or owner-occupied, to have permanently installed, safe, functioning heating facilities and an approved power or fuel supply capable of holding 68°F in all habitable rooms, bathrooms and toilet rooms, and it specifically bars using a stove or other cooking appliance as a stand-in for real space heating. Section 602.3 layers a landlord-specific duty on top: any owner or operator who rents, leases or lets a dwelling unit, rooming unit, dormitory or guestroom and who has agreed, expressly or by implication, to furnish heat, must actually supply it during the heating season, October 1st through April 30th, and keep the space at no less than 65°F.

There is one narrow exception: on days when the outdoor temperature drops below the winter outdoor design temperature set for the area in the plumbing code Shoreline has adopted, the landlord is not held to the minimum indoor temperature as long as the heating system is running at full design capacity; a broken or undersized furnace does not qualify for that exception. Because these sections sit inside the property maintenance code rather than the landlord-tenant chapter, a tenant without adequate heat has a code violation to point to independent of any civil landlord-tenant claim under state law.