Each bill was amended in their respective committee but essentially still allow an RV to park in the driveway for an undetermined amount of time. Although the bills have officially renamed the living conditions from a “home on a wheels” to a “mobile dwelling,” most of the defined uses of the type of dwelling allowed is still not designed for permanent habitation. The exception is both bills now allow at least one type of mobile dwelling that is designed for permanent living and is built in accordance to the state building code—a “tiny house on wheels.”

Both bills also amended language to require potable water connections, but the bills slightly diverged in the rest of the changes adopted.

Here are the changes the House committee made to HB 1443

• Removes language related to a city or county determining that a housing development cannot be adequately served by water, sewer, stormwater, and transportation systems.
• Requires cities and counties to use standard permitting and inspection procedures for new utility hookups, including electric, water, and sewer.
• Prohibits a common-interest community located in a county from enacting any new restrictions that would prohibit at least one mobile dwelling on each residential lot.

Here the changes the Senate committee made to SB 5332

• Updates that the lot has already been determined to be able to serve the additional sewer demand, but is now silent on water, stormwater, and transportation systems 
• Allows cities and counties to inspect storage tank, sewer, and sanitary connections to ensure they are not leaking or polluting.  
• Requires the mobile dwelling unit be maintained so that it can be moved at any time. Requires the mobile dwelling unit meet the setback requirements of the underlying zone.  

Mobile dwellings bill on the move

January 24, 2025

Companion bills propose a new mandate for GMA cities – allowing a “home on wheels,” commonly known as an RV or travel trailer, to park and plug-in on every residential lot.

HB 1443, sponsored by Rep. Mia Gregerson (D–SeaTac), and SB 5332, sponsored by Sen. Sharon Shewmake (D–Bellingham), would require every residential lot in the urban growth area subject to the Growth Management Act (GMA) to allow an RV or trailer under the following conditions:

• The lot has a house
• The lot can be adequately served by water, sewer, stormwater, and transportation systems
• The “home on wheels” must be connected to power
• If the mobile home has its own plumbing it must be connected to the house
• If the mobile home does not have plumbing, its occupant must have access to the house’s facilities

The bill requires cities and counties to “enforce standard inspection procedures for utility hookups to homes on wheels” but cannot inspect the wheeled home itself. Inspections are typically part of a permit process. Is the expectation that property owners are pulling a permit for this use?

Dates to remember

HB 1443 will be heard in the House Housing Committee on Monday, January 27 at 1:30 pm.

SB 5332 will be heard in the Senate Housing Committee on Wednesday, January 29 at 10:30 am and voted on Friday, January 30 at 10:30 am.