Factory-Built Housing

Introduction to Factory-Built or Off-Site Construction Building Standards

Off-site construction refers to structures or components built at a different location (a factory) than the location of use. Factory-built homes are also referred to as prefabs. Different building codes are used for the various kinds of housing built in factories. For instance, manufactured housing uses the HUD building code and modular uses the International Residential Code developed by ICC.

THIA Board Members David R. Tompos and Nick Mosley sit on the ICC-OSMC Committee—stands for Off-Site Modular Construction.  The goal of this committee is to create standards for housing, built "off-site" in factories. These standards include transportation, inspection, design, plan approval, quality control, planning, definitions, etc. Everything from conception to delivery of a unit on a job site. They are primarily procedural standards that will then go under review by ICC (International Code Council). Learn more here.

“I am the representative for the tiny house industry to make sure as a new/ upcoming industry, our voices are heard. During the meetings, there have been various discussions of tiny homes and how they fit into the much larger Modular construction industry. Before this committee, they have generally been excluded.

The goal is to adopt tiny home building practices into the greater body of the standards vs. creating a separate space that would leave it up to the authority having jurisdiction (AHJ) to choose whether or not they want to allow tiny homes (and this has been achieved!).

- Nick Mosley, California Tiny House CEO & National Builders' Commitee Co-Chair

"Becoming a THIA member helped me bring tiny houses to my town.  Now, I can live where I want and how I want, legally."

-Jessica B. San Jose, CA

"We entered the Tiny House on Wheels industry because we felt that this product is both of vital future importance, and also that the industry would benefit
from experienced professional construction and standards. THIA stands for exactly these things which are the reason we started building tiny homes in the first

With THIA I feel confident that we are moving towards a fair and correct set of national standards, and as this is an organization that has a real purpose, not just a name and a sticker, we will be a member moving forward. It's also fantastic to have somewhere to get some feedback or secure a referral."

- Jerry Terry, Decathlon Construction

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