Van Buren Township

Tornado Mobile Home Safety

Basic Mobile Home Facts


Mobile Home - A prefabricated home (manufactured off-site) constructed prior to 1976.

Manufactured Home - A prefabricated home constructed after 1976 in accordance with the HUD manufactured Home Construction and Safety Standards.

Site Built Home - Any home that is not prefabricated (i.e. any home built on site conforming to the local building code).

Modular Home - A prefabricated home designed and constructed to conform to the local building code in effect at the final location of the home.

So what happened in 1976…

In 1974, Congress passed the Federal National Manufactured Housing Construction and Safety Standards Act commonly referred to as the HUD code. The new Hud Codes were put into place on June 5th, 1976. After this date “mobile” homes were now to be referred to as “manufactured” homes due to the changes in construction, design, performance and installation. Homes that meet the post-1976 HUD codes are assigned a HUD tag proving that “to the best of the manufacturers knowledge” the home is built to the

HUD requirements. A “data plate” is also placed on the home that can list equipment, wind zone and other information. HUD’s Manufactured Home Construction and Safety Standards and its Model Manufactured Home Installation Standards categorize the United States and many of its territories and protectorates into three wind zones. The entire state of Michigan is in Zone 1, which is designed for the interior of the country not affected by hurricanes. In Zone 1, the homes are designed to generally resist wind speeds of approximately 70 MPH.

Michigan mobile home park storm shelters…

Around 1995, the Michigan Manufactured Housing Commision established a rule that all new

mobile home communities must have a storm shelter onsite. Those parks that existed prior to 1995 were

grandfathered into this rule. As a result, many mobile home parks established before 1995 do not have

storm shelters onsite.

General Statistics:

● There are around 1,060 mobile home parks in the state of Michigan.

● Around 6% of existing single family homes in Michigan are mobile or manufactured.

● Detroit is one of the top 10 retail markets in the country for manufactured housing.

● 72% of all tornado fatalities occur in homes.

● 54% of housing fatalities occur in Mobile/Manufactured Homes (MH).

● Research has indicated that MH residents are 15-20 times more likely to be killed in a MH

compared to a permanent home in the event of a tornado.

● Typically, complete destruction of a MH is expected for wind loads approximately 45% of those expected to destroy a permanent home.

Mobile and Manufactured Housing (MH) Frequently Asked Questions

If you live in a MH, what are the best sheltering options?

● Officially, the NWS, NOAA, and FEMA all suggest that mobile/manufactured housing residents flee their homes for sturdier shelter.

However, this is not such an easy task for a large number of MH residents due to a number of factors.

The following assumptions are often made in this situation.

■ Residents have a car

■ Residents know where sturdier shelter is located

■ Residents actually know WHAT “sturdier” shelter looks like

■ Residents know their own homes geographic location (relative to the storm movement)

■ Community shelter (if one is available) is actually open

■ Whether pets are allowed or not

■ Whether the shelter is at capacity

Recent research has shown that due to the greater number of MHs being located in rural locations, community shelters are not the solution. Rather, the retrofitting of existing structures so that they are more resistant to strong winds may be more practical.

Typical structural upgrades such as adding tie-downs and anchoring can be done at a fraction of the total cost of a new MH. (under $2,000)

MH resident sheltering best practices: Have a sheltering plan. Have a place that is of a sturdier structure (preferably a tornado shelter or a relatives/friends home with a basement) to go to and know how long it takes to get there. The best option is to begin moving toward this sturdier structure or designated tornado shelter when a tornado WATCH is issued.

Should you really lay in a ditch vs riding it out in a MH?

Not necessarily, but this is still widely debated. Typically, laying in a ditch or ravine should be a last resort to sheltering from a tornado. This type of protective action is suggested to those outside who cannot make it to adequate shelter.

That being said, some groups (e.g. CDC) suggest that MH residents may actually be better off fleeing their homes and lying flat in a ditch or culvert. Other researchers have noticed that vehicles may offer more protection than MHs during tornadoes as well. This is more often the case if you have a newer vehicle equipped with airbags, in which case, you

will want to turn the vehicle on so that the airbags can deploy if need be. Either way, the consensus is that the best course of action is to flee the MH for sturdier protection.

What causes the most serious injuries/deaths in MH during a tornado?

When the structure is moved off its foundation and starts to tumble/break apart. Modern manufactured homes (built after the 1976 HUD requirements) are actually well built and can withstand lower end tornadoes. However, a common issue is improper, non-existent, or compromised anchoring of the structure to the ground. Once the structure's

foundational integrity is compromised, rolling and other movements can cause the home to fall apart. The key point is the anchoring.

Is there any advice to give as far as securing a MH that can not be permanently placed (such as a rented lot)?

Here is more detailed information from a structural engineer who specializes in this issue.

Information on anchoring from FEMA (located in section 7):