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McGarry and Madsen's home inspection blog for buyers of  

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Does an addition to a mobile home have to comply with the HUD Code?

Wednesday, October 3, 2018

The HUD construction standards apply to the manufacture of a mobile home up until it has been inspected and approved by an In-Plant Primary Inspection Agency (IPIA), receives a HUD sticker, and heads down the highway for delivery. After that, there are still some HUD Code standards for installation of the home at its final destination but, once the home is sited, HUD’s jurisdiction ends.

   Any additions or repairs to a mobile/manufactured home only have to comply with local building codes. But there are several important issues to consider when adding to a manufactured home:

1) The exterior wall of a HUD Code home is only engineered to support its own roof structure. The photo above shows the roof structure of an addition that bears on the fascia of a mobile home—which is not allowed and puts additional weight on a manufactured home wall that was not designed to carry it. Any addition should be self-supporting, unless a “host beam” has been installed at the factory for the future addition. See our blog post What is a "host beam" at a mobile/manufactured home? for more on this.

2) A manufactured home needs two unobstructed exterior doors for emergency exit in a fire. An addition that eliminates or obstructs direct access to one of the exit doors is a safety hazard. The HUD code also requires these two safety features for exit doors:
        a) Shall not be located in rooms where a lockable interior door must be used in order to exit. [24 CFR 3280.105(a)(1)]
        b) One of the required exit doors must be accessible from the doorway of each bedroom without traveling more 35 feet [24 CFR 3280.105(a)(2)(iv)]

3) The crawl space under a mobile home needs to have ventilation openings. If an addition eliminates a significant area of vented skirting and reduces the cross-ventilation air flow under the home, the buildup of moist air in the crawl space can cause mold problems in the home over time, especially if the bottom board (also called the “belly wrap”) is no longer intact.

4) If your home is still within the manufacturer’s warranty period, an addition may void the warranty. Check your warranty paperwork.

5) If you decide to relocate your home, the addition complicates the move. It cannot be moved and will require demolition. Also, any openings in the exterior of the home cut for the addition will have to be repaired, and plumbing and electrical wiring restored to their original configuration.    

    Go to our HUD-CODE FOR MOBILE HOMES page for a listing of our other HUD-code articles. Also, see our blog posts What walls can I remove in a mobile home? and What do I need to know about building an addition to a mobile home?

       Visit our MOBILE/MANUFACTURED HOMES  page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.

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