The Issaquah Planning Policy Commission on Jan. 9 reviewed proposed amendments to the city's noise and accessory standards that would make it easier to install heat pumps, air-conditioner condensers and similar residential mechanical equipment while requiring mitigation when equipment exceeds state limits.

City staff said the proposed changes respond to modern equipment noise levels and the growing need for residential cooling. "Mechanical equipment is referring to heat pumps, air conditioner condensers, and other similar heating or cooling home amenities," Madeline Nelson, a planning intern, told commissioners during the presentation. Nelson said state residential noise limits are 55 decibels during the day and 45 decibels at night as measured at the property line and that many modern units are manufactured at 60'to'70 decibels, making the state standard difficult to meet at shared property lines in townhomes and middle-housing configurations.

Why it matters: Commissioners said the change affects neighborhoods as the city sees more middle housing and infill. The proposed code aims to balance homeowners' ability to install cooling equipment as climate-driven heat events increase with protections for adjacent residences.

Key provisions presented by staff include: an exemption for single-family residential from the state property-line standard, replacing it with a flat 73-decibel limit (the staff presentation said this is equivalent to the AHRI RE 270 outdoor-unit standard); a requirement that when equipment would exceed the state property-line standard the owner must implement practicable mitigation; and a non-exhaustive list of mitigation options such as siting equipment away from neighbors, using vegetative or fencing buffers, installing quieter components, or using a night-time quiet mode where available.

Assistant Planning Director Steven Badua told the commission mitigation will be enforced through the building-permit and inspection process: permits for installations would not be approved unless required mitigation is installed and inspectors will verify compliance. He said code-compliance procedures and nuisance/noise complaint mechanisms would be used if equipment remained over allowable levels after installation.

Commissioners raised practical concerns. Commissioner Kress and Commissioner Kennedy asked whether mitigation measures could damage equipment or reduce efficiency; Badua said inspectors and installers typically coordinate to avoid designs that harm equipment. Multiple commissioners noted clustered multifamily or townhome developments could create a cumulative "humming" effect even if each unit individually meets the standard, and asked whether separate rules for higher-density areas were needed. Commissioner Zach Roth asked whether 73 dB equipment is readily available; staff said most equipment is at or below about 70 dB and that louder models exist but can often be mitigated.

Generators: Commissioners asked whether the proposal would apply to standby generators. Staff said the draft amendment under discussion focuses on heat pumps and air-conditioning equipment and does not extend the exemption to generators; generators remain subject to other building-code requirements and general noise enforcement. Several commissioners said they were comfortable keeping generators outside this amendment given the different use patterns and regulatory treatment.

Discussion vs. decision: No formal code amendment was adopted at the meeting. Commissioners provided feedback on the draft language and mitigation options; staff said they will return with refined code language and will include enforcement and inspection details in the permit process before public hearings.

Next steps: Staff told commissioners the proposed amendments will return as a formal draft for additional public review and hearings (staff signaled a public hearing timeline in early 2025 as part of the broader code amendment process).