Case Study: Tiny Home Becomes Becomes Detached Accessory Dwelling Unit in Lynnwood, Wa.
Guest Post From Kuro Galley With Carrieve Hluses NW, LLC
Carriage Houses NW has a really exciting development we want to share regarding backyard cottages. The city of Lynnwood recently approved the placement of one of our tiny houses on wheels onto permanent foundation as a backyard cottage, also known as a detached accessory dwelling unit (DADU). Our tiny houses are licensed in Washington State as Park Model RVs, which means they conform to a different set of build requirements prescribed for park models and travel trailers, rather than modular homes. They go through a rigorous approval process which includes structural engineering and systems inspections for framing, insulation, electrical wiring, and plumbing. They leave our factory with an L&I insignia that they meet or exceed all requirements.
When our customer, Randy Thompson, approached the city of Lynnwood to see if they would allow a certified tiny house as a DADU, they approved it on the condition that it be attached to a permanent foundation. And this brings us to the second exciting part of the story! A typical stem wall foundation requires significant soil excavation, time, and expense. We submitted a request to the city to allow us to use something called diamond piers as an alternative foundation. Diamond piers are small, engineered cement blocks that are dug into the ground, and then steel posts are run through them until they hit bearing soil. It’s much less invasive, quicker to install, and often costs less than a traditional cement foundation. The city approved the request and we had the house installed and attached to the diamond piers with very little excavation or disruption of the natural landscape, in less than two days’ work.
This application of a tiny house permitted to be attached to a residential property represents a revolutionary development as the Pacific Northwest faces a housing crisis that is projected to last for years to come. Carriage Houses Northwest is excited to have been part of this innovative approach which provides homeowners more flexibility and options for adding living space to their property.
About Carriage Houses NW
Did you know that tiny houses on wheels are required to be licensed as travel trailers or Park Model RVs (depending on width)? CHNW is licensed as a Factory Assembled Structure Manufacturer of travel trailers and park model RVs. That means our models are structurally engineered and meet rigorous safety and build standards. They leave our facility with the Washington State Department of Labor & Industry’s RV insignia. Additionally, our tiny houses are certified by Pacific West Associates, a nationally recognized RV inspection and approval agency.
In addition to being a tiny house manufacturer, we are a modular home manufacturer as well as a licensed, bonded general contractor. Our primary business is building beautiful tiny houses on wheels. When appropriate, we can provide additional services to our customers who may need site work or other solutions outside of our factory work. Just ask us and we’ll see what we can do for you!