True Tornado Magnets
Or Manufactured Myth?

Almost one out of three new homes sold in the U.S. is a manufactured home. In some states, particularly in the South, manufactured homes make up more than half of all new homes purchased. Even so, a number of misconceptions about them persist. Many people falsely still believe that factory-built homes:

• are more vulnerable to fires.
• are tornado magnets.
• don't retain their value.
• aren't built well.
• look like trailers.

These misconceptions are based on outdated stereotypes of the manufactured-housing industry. But pre-fab homes have come a long way in the past two decades. Here is a rundown of their myths and realities to bring you up-to-date on this housing option.

Myth: Manufactured homes are more vulnerable to fires than other single-family homes.

Reality: According to an annual report by the Oklahoma State Fire Marshal's Office, manufactured homes are no more prone to catching fire than site-built homes. In fact, according to the Foremost Insurance Company, an insurer of mobile homes in Caledonia, Mich., site-built homes are more than twice as likely to experience fires than manufactured homes. The company reports that 17 of every 1,000 site-built homes catch fire, compared to eight per 1,000 manufactured homes.

"Manufactured homes are the only homes with a national building code," says Richard Wettergreen, assistant vice president of marketing communications and research at Foremost, which is part of the Farmers Insurance Group. "The fire study indicates that [U.S. Department of Housing and Urban Development (HUD)] standards, adopted in 1976, have a positive effect on fire safety in manufactured housing."

When construction methods and standards are considered, living in a factory-built home appears to hold a distinct and safe advantage.

Myth: Manufactured homes are tornado magnets.

Reality: HUD revised its wind-safety provisions in 1994 after an assessment of the destruction caused by Hurricane Andrew, which struck the southern tip of Florida and the Gulf Coast regions of Louisiana in 1992 with winds in excess of 150 miles per hour.

HUD's wind-safety standards in areas prone to hurricane-force winds require that manufactured homes be resistant to winds up to 100 and 110 mph, depending on the area. The standard for manufactured homes in hurricane-prone areas is now far more stringent than the current regional and national building codes for site-built homes in these areas.

Each state has its own regulatory standards for how manufactured homes are installed and anchored. Only by properly installing and anchoring one of these structures can a manufactured-home owner meet the wind-resistance standards. As a required part of the storm-protection provisions of the HUD code, the manufacturer must include installation instructions to properly support and anchor each manufactured home sold.

There is no scientific evidence to suggest that manufactured structures attract lightning or high winds, including tornadoes. The reality is that older mobile-home parks were placed in rural settings or on the outskirts of municipalities, which have a tendency to be in paths of lesser resistance for damaging winds or storms that might pass through. Newer manufactured homes also are much more prevalent in rural settings. Thus, they, too, often are located in areas that may be more open and vulnerable to severe weather.

In most of the U.S., manufactured homes, when properly installed and anchored, must be able to withstand sustained winds of up to 70 mph. However, well-installed manufactured homes in these areas can normally withstand much higher winds without appreciable damage.

A direct hit from a tornado will destroy practically any structure. The most powerful tornados will completely destroy even the strongest building. The fiercest tornadoes will peel the pavement off the road, leaving just dirt.

Myth: Manufactured homes do not retain their value as well as site-built homes.

Reality: This point is false. Manufactured homes are on par with site-built homes when it comes to depreciation. Homes, regardless of type, in declining neighborhoods and areas with lower real-estate values, may depreciate despite the condition of the structure on that property. If a manufactured home is installed on a permanent foundation -- and if, in the case of a multi-section structure, the sections are properly married, the ground pad drains properly, and the whole building is strongly anchored -- the longevity of the home will equal that of any similar site-built house. The cost of the manufactured home is significantly lower than that of the site-built home, and the manufactured-home buyer will enjoy instant price appreciation as the market value quickly will exceed what the home actually costs.

Myth: Manufactured homes are not as well-built as site-built homes.

Reality: Site-built and manufactured homes are constructed with the same materials, including windows, doors, roof trusses and shingles, siding, flooring and most other components. In fact, many manufactured homes use 2 x 6 exterior wall studs, instead of the standard 2 x 4 studs almost always used in the construction of site-built homes.

Also, many have steel straps holding the walls to the floors and the roof to the walls, so the strength of the entire structure is superior to that of an average site-built house. Required plumbing is usually CPVC, which is generally considered the superior material for fresh, gray or black water at any temperature without breaking down like polybutylene or standard PVC (polyvinyl chloride).

When you inspect one of these homes, you will notice that the gaps between the floor and the bottom of the interior doors seem to be abnormally large. HUD requires each manufactured home to "breathe" properly. The cooler air must flow from room to room over the floor, as the warmer air does the same just below the ceiling through vents over the doors (primarily bedroom doors). This provides for a proper air exchange, which equalizes the temperature and provides a greater volume of fresh air throughout the house. Very few site-built homes use this method.

All manufactured homes are built on jigs, platforms which are dimensionally exact. Thus, every manufactured home is perfectly plumb when it leaves the factory.

Unlike site-built homes, manufactured houses also have to be built to stringent HUD standards. Built in a controlled factory environment, manufactured homes are tested and inspected by HUD for construction, strength and durability, design, fire resistance, energy efficiency and performance of internal systems.

HUD inspectors check each home at every factory. Not one home leaves the factory without a red HUD tag, which certifies that it has passed HUD's rigid standards. These tags can be attached only by a HUD inspector.

Myth: Manufactured homes look like trailers.

Reality: Obviously, quite a few people know better than that. But not many people know about the progress the industry has made in the past two decades. Floor plans now range from a few hundred square feet to more than 3,000 square feet. There are many different models, including ranch styles, Cape Cods, California bungalows, split logs, and Mediterranean styles with stucco walls and tiled roofs. Plus, there is an ever-growing assortment of two-storied beauties.

Pre-fab homes, many in double, triple and, in some cases, quadruple-wide sizes, are quickly becoming the preferred housing alternative to conventionally built homes. As they grow to be common in more neighborhoods, old-fashioned concepts about them will fade away.

-- Mr. Taylor is a consultant on manufactured housing and free-lance writer in Bethune, S.C. This article has been adapted from his book "Manufactured Homes: The Buyer's Guide" (Cycle Publishing, 2004).

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