Previously, Washington’s rental laws didn’t have much guidance on new cooling units. Slatter said that landlords could refuse to let a tenant install one. The new law, by contrast, states that renters can now install a portable AC unit, as long as a landlord hasn’t explicitly written a ban into the lease.

The law, which went into effect in June, includes specific restrictions depending on the kinds of AC units a tenant is looking to install. For a window unit, here are the restrictions:

• A tenant must give the landlord two days’ notice before installation.
• The device cannot prevent a window accessible from the outside to be locked.
• It cannot require excessive brackets that would damage the window frame warranty.
• The device must be safely secured from falling out of the window.
• The landlord’s insurance policy must allow window-mounted units to be installed.
• Landlords can require inspection of window-mounted units after installation.
• Fewer restrictions apply to other types of AC units, like floor-mounted devices and saddle-mounted units.