One of the biggest challenges of building a tiny home is making sure it’s up to code. This is why so many have wheels—it can be easier to register as a recreational vehicle (RV) than legally build a tiny house with a foundation.
But a bill currently in the Washington State House, HB 1085, would make building a tiny home with a foundation a little easier by allowing counties, cities, and towns to eliminate minimum room or gross size requirements if they choose to do so, assuming it won’t jeopardize anyone’s safety.
“The legislature finds that there is a growing need for ecologically sustainable and affordable housing, and small home construction is a way to meet this need,” opens the bill’s text. “The legislature also finds that regulations mandating a minimum gross floor area for single-family dwellings, such as minimum floor or room area requirements, that do not further fire, life safety, or environmental purposes, objectives, or standards prevent construction of small homes.”
The bill is sponsored by Rep. Brian Blake (D-19), plus two fellow Democrats and three Republicans—but tiny houses have not historically been a partisan issue in the Legislature.
Rep. Blake also introduced a bill in 2015 with a similar goal: to eliminate the minimum gross floor space requirement in municipalities with populations of 125,000 or fewer. The bill made it through the house and made significant progress in the Senate, but ultimately died before it could come to a vote.
As testimony before the 2015 bill pointed out, little houses on wheels aren’t mortgaged or rented like houses on foundations—so allowing them to be put on foundations would make them more affordable for many.
Current state building code requires that all homes have at least one "habitable room" of at least 120 square feet, and 70 feet for any additional habitable rooms, with a minimum dimension of 7 feet. This had been adopted from the International Residential Code, which has since axed the 120 square foot requirement.
You can build a pretty small house within the requirements, but they’re still pretty limiting for folks that want to go for the tiniest of the tiny.
Tiny house zoning regulations: What you need to know [Curbed]