Overview of ESSB 6200 and Its 2026 Impact
ESSB 6200, as signed by Governor Ferguson on March 24, 2026, has become effective as of June 11, 2026. The law amends both:
- RCW 59.20.070 (Manufactured/Mobile Home Landlord-Tenant Act, Prohibited Acts by Landlord “MHLTA”)
- RCW 59.18 (Residential Landlord-Tenant Act “RLTA”)
Key Rule: Landlords Can’t Prohibit Portable Cooling Devices (With Exceptions)
Beginning June 11, 2026, Washington landlords under the RLTA are prohibited from preventing tenants from installing portable cooling devices of their choosing within their rentals except under specific conditions.
Further, a landlord may not require a fee for the use, inspection, or installation of a portable cooling device, but a landlord may charge for rental of a portable cooling device rented by a tenant from a landlord or charge a tenant for damages to the premises as a result of the cooling device.
What Counts as a “Portable Cooling Device”?
Portable cooling devices are defined under the law as air conditioners or portable heat pumps, and include devices mounted on a window or designed to sit on the floor.
“Portable cooling devices” do not include any of those whose installation or use requires excessive alteration to the dwelling unit – such as the use of brackets that would void the warranty of the window or frame or puncture the exterior of the building. “Saddle-mounted portable cooling devices” are defined as able to hang over the windowsill with exterior and interior components rather than sitting on top of it, and are not considered by the law to be “window-mounted portable cooling devices,” which are defined as sitting in the window and are not otherwise mounted on the floor.
When Landlords Can Restrict Cooling Devices
Though tenant rights are expanded, landlords retain limited authority to restrict installation when justified.
- the dwelling already has a permanently installed and fully operational heat pump
- it would violate state or building codes, state law, or federal law
- it would violate the device manufacturer’s written safety guidelines
- it would cause unreasonable damage to the premises or render it uninhabitable or require electrical supply to power the device that cannot be accommodated by the existing power service to the building
- the window the tenant wants to install the unit in is a necessary egress from the dwelling unit and the unit would interfere with that use as an egress
- the device would interfere with the tenant’s ability to lock a window that is accessible from the outside
- the device cannot be secured in a way that would prevent it from falling out of the window
- the landlord’s insurance policy for the dwellings expressly prohibits or restricts the use of window-mounted cooling devices, and the landlord has provided written evidence of such restriction to the tenant
Landlord Rights: Conditions, Notices, and Inspections
Landlords can require the devices be adequately drained to prevent damage to the unit or building, and the landlord can require that a window-mounted portable cooling device be subjected to inspection after installation, servicing after installation, or that the tenant provide two days’ notice to the landlord prior to the installation of the window-mounted device.
If a landlord restricts or prohibits the installation of window-mounted portable cooling devices, the landlord must notify tenants in their leases of their rights, responsibilities, and any restrictions or prohibitions related to the installation of a window-mounted portable cooling device.
Under the MHLTA, similarly to the restrictions under the RLTA, beginning June 11, 2026, a landlord may not prohibit or restrict a tenant from installing a portable cooling device of the tenant’s choosing unless installation of the device would violate state or local building codes or state or federal law, violate the device manufacturer’s written safety guidelines, cause unreasonable damages to the premises, or require an electrical supply to power that cannot be accommodated by the power service to the mobile home or park.
As many buildings and homes in Seattle, and Washington State broadly do not have heat pumps or central cooling installed, it falls on landlords to be aware of these new requirements. Each of the listed types of portable cooling devices in the law have their own properties, such as power requirements, ease of installation and removal, condensation/water risks, and average cost. Being aware of the properties of different portable cooling devices in advance will enable landlords to proactively make decisions regarding potential risks and limitations of the property or management considerations.
Landlords must proactively inform their tenants of any necessary restrictions on the installation or use of specific portable cooling devices in their properties, and leases should be revised to comply with the law. Landlords should not be blindsided by improperly installed devices, devices that can cause excessive damage, or devices that would otherwise not be allowable at their properties due to law, electrical load, or insurance restrictions.
A knowledgeable and competent attorney can assist landlords in navigating the requirements of this new law and revising any lease agreements, addenda, and disclosures necessary for tenants and landlords to responsibly beat the heat this summer and in the future.
