Proper installation of your manufactured home and a few precautions will help you to prevent storm and fire damage. The Forty-Second Congress of the United States passed the National Manufactured Housing Construction and Safety Act in 1974; however, the law became effective on June 15, 1976. This act ensured that all mobile homes would be built according to tough national standards. The name mobile homes was ofﬁcially changed to manufactured homes in 1980.
Today, manufactured housing accounts for approximately 10 percent of the total housing stock in the United States and 25 percent of its annual, new, and residential construction and home sales. The 2000 Census estimated that approximately 620,000 or more manufactured homes exist in Alabama. Manufactured housing is affordable and convenient, and Alabama legislation reports that mass-produced housing meets the needs of many people, while reducing construction and building costs.
Manufactured Home Structure
A manufactured home is new when it is in the possession of the manufacturer, dealer, or ﬁrst purchaser. It is usually transported in one or more sections. A manufactured home can measure 8 body feet or more in width and 32 body feet or more in length when erected on site and built on a permanent chassis-designed for use as a dwelling–with or without a permanent foundation. It contains all the added features of a home complete with plumbing, heating, air-conditioning, and electrical systems. Although standards for manufactured housing have greatly improved in recent years, older manufactured homes do not have the safety features now required by federal law in the Manufactured Home Construction Safety Standards, Part 3280. However, as with any home regardless of age, take special precautions to guard against possible hazards, such as severe storms or ﬁres.
Manufactured homes are relatively light, compact structures and cannot resist high winds or ﬁre as well as conventional homes. Destructive tornadoes and hurricanes hit Alabama each year. Baldwin and Mobile counties, Wind Zone II (see Table 1), encounter sustained winds of 100 miles per hour or more. Placement of manufactured homes can add protection against strong winds. Placing the homes near natural barriers, such as trees and small hills, or turning the narrow end of the home into the prevailing winds can greatly reduce the windsʼ lifting force. In addition, skirting, such as a lattice-type or louvers, should be used on all sides to allow air under the home.
Tie-down systems can be used to secure any expanding units, porches, and/or awnings attached to storage sheds if they are blocked and constructed like the home. The number of ties you need depends on the size of your home and the force of the winds common to your area. Ensure that your home is constructed for the correct wind zone before placing your home in that zone. For example, coastal region dwellers need stronger tie-down systems than those living in Central and North Alabama. Double-wide manufactured homes need only frame ties in Wind Zone I. A home constructed for Wind Zone II may be placed in Wind Zone I, but a home constructed for Wind Zone I cannot be placed in Wind Zone II. If your home is not outﬁtted for tie-downs or has fewer than you need, place all additional over-the-top ties at studs and rafters.
- The required number of anchors for each side of a manufactured home and building is shown in Table 1. This is to be used if the manufacturerʼs installation instructions are unavailable. If the manufacturerʼs installation instructions are available, the anchoring requirements must be followed.
- Homes with a HUD label are not required to have vertical ties in Wind Zone I.
- All multisection homes should be fastened and sealed together according to the home manufacturerʼs instructions.
- A Wind Zone I home cannot be installed in Wind Zone II.
- An optional anchoring system can be used only if it has been approved by the Alabama Manufactured Housing Commission
(Commission) in accordance with 535-X-13-09 and does not conﬂict with 535-X-13-06 (11).
Table 1. Recommended number of tie-downs.
Wind Zone II—Hurricane Zone
|*Length of mobile home (ft)||** Number of vertical ties||Number of diagonal ties|
Wind Zone I – Non-Hurricane Zone
|*Length of mobile home (ft)||**** Number of vertical ties||*** Number of diagonal ties|
*Manufactured home length excluded the draw bar.
** The Federal Manufactured Home Construction and Safety Standards set forth standards of construction for homes in different wind zones. Only homes constructed for Wind Zone II may be placed in Wind Zone II.
*** If pier height is more than 24 inches, a diagonal tie should be added for every 12 inches (or a portion thereof).
**** Homes without a HUD label must have three vertical ties per side in Wind Zone I.
To anchor your manufactured home or home unit, use a combination of ties, anchoring equipment, and ground anchors. When properly designed and installed, these will resist the overturning or sideways movement of the home caused by wind. All installers of manufactured homes must be certiﬁed and approved by the commission. American National Standards Institute (ANSI) approves all tie-down and anchor devices that have been tested according to their standards. Systems and devices must also meet the standards of the Department of Housing and Urban Development and/or the American Society of Testing of Materials. The commission must approve all blocking, anchoring, and tie-down devices or systems before they can be used in Alabama for the installation of manufactured homes or buildings.
Figure 1. Anchor. Foremost Insurance Company, 2004. How to install tie-downs and anchors.
Tie-down anchors should be made of 7/8-inch, 3¼-inch, and 5/8-inch steel rods (depending on the soil classiﬁcation) that are strong enough to withstand 4,725 pounds of stress at a minimum. In sandy or loamy soil, use a screw auger anchor (see Figure 1). A list of approved products may be obtained from the Alabama Manufactured Housing Commission.
Most anchors have tensioning devices that connect the anchor to a steel strap. “All tie-down straps and devices must be tested and approved. Straps must be type 1, ﬁnish B, grade 1 steel strapping, 1¼-inches wide, and 0.035-inch thick as stated in federal speciﬁcations for strapping steels and seals FS QQ-S-781H-1974” (Sloan, 2001). The pier foundation should be placed on stable soil (Sloan, 1975) with all grass and organic material removed. Pier foundations are installed directly under the mainframe of the home or building. Pier speciﬁcations are as follows:
- Piers should not be more than 6 feet apart on center when using a minimum pier foundation of a 16-inch by 16-inch concrete pad or equivalent in the minimum soil bearing capacity of 2,000 pounds.
- Piers should be no more than 2 feet from each end of the frame.
- The minimum pier foundation should be a 16-inch by 16-inch by 4-inch concrete pad, precast or poured in place of a concrete slab.
Before sinking any anchors, locate the manufactured housing utility lines; contact Alabama One Call at (800) 292-8525. If you will live in a mobile home park, ask the park owner for anchor speciﬁcations, or contact a building inspector to ensure safety in tie-downs and anchoring for wind and soil conditions.
Note: In the event of a tornado or a hurricane, go to the nearest community shelter–do not stay in your manufac-tured home.
Flooding often follows severe storms. The manufactured housing site should be elevated at or above the base ﬂood elevation. Site preparation should be followed for any home installation regardless of whether itʼs in a special ﬂood hazard area. However, if the home is to be installed in a FEMA-identiﬁed special ﬂood hazard area, the installation must be in accordance with the National Flood Insurance Program (NFIP) ﬂood plain management criteria in addition to HUD manufactured housing criteria. Contact the local building ofﬁcial, town clerk, or mayor in a city or town before placing a manufactured home in a ﬂood hazard area. In the event the home is to be placed in the unincorporated area of the county, contact the county commission ofﬁce for the proper permitting agency. Before placing a manufactured home in a ﬂood hazard area, apply for a permit and provide the local permit ofﬁcial with a FEMA Elevation Certiﬁcate. Have an emergency plan of escape for you, your family, and for safeguarding valuables. In the event a permit ofﬁcial cannot be located, contact the State National Flood Insurance Program coordinator in Montgomery, Alabama, at the Alabama Department of Economic and Community Affairs/Ofﬁce of Water Resources at (334) 353-1966 for assistance.
Fire prevention should be a primary concern for all mobile and manufactured home dwellers. Structures built after 1976 meet National Fire Protection Association standards for ﬁre resistant materials, unlike earlier structures that are likely to have highly ﬂammable material. Because your escape time may be limited, mobile home dwellers should be aware that homes built before 1976 may have high awning-type windows, single doors, or other unsafe design features that make escaping difﬁcult.
Since the enactment of the National Manufactured Housing Construction Safety Act was passed, any approved manufactured homes must meet federal ﬁre safety standards and the National Electric Code. Speciﬁcations for ﬂame safety must also be met to protect heating, water heating, and cooking areas. In addition, home smoke alarms, emergency escape windows in sleeping quarters, and a minimum of two accessible exits are also required.
Inspect your furnace closet for loose wiring to ensure the wiring is well away from the ﬂues. Furnace and water heater ﬂues could ignite the covering on any loose hanging wires. Current furnace and water heaters are lined with nonﬂammable gypsum wallboard and have switches and temperature controls for adjustments. Make sure that all ﬂues are aligned with the appliance and the roof jack to avoid separating furnace or heater ﬂues that can direct hot air at ﬂammable surfaces and cause smoke and carbon monoxide to escape into the home.
The furnace compartment should never be used for storage. In case of emergency, know how to shut down the furnace. Gas or oil furnaces are equipped with a fuel shut-off valve and a wall switch near the closet or in the circuit breaker panel to control the blower.
Keep emergency numbers nearby for plumbing or furnace repair inside the furnace compartment door. Also, keep the most recent furnace inspection sheet handy.
All fuel lines for your furnace, water heater, and appliances should be checked for leaks and loose connections. Never use a match to check for gas leaks. Instead, use a soap and water solution to look for bubbles in the gas lines. Be careful when checking the joints behind the stove. For oil leaks, look for traces of oil if the lines are dry and clean otherwise.
Kitchen range ﬁres account for half of all ﬁres in manufactured homes. To avoid ﬁres, be sure the gas company adjusts your gas range to avoid pilot light failure and explosions. Your responsibility is to keep grease from building up on the surface of your range and exhaust hood.
If a ﬁre should occur while cooking, always keep a lid close to smother a burning pan. Keep baking soda to put out a grease ﬁre.
All manufactured homes should have a mounted multi-purpose ABC ﬁre extinguisher in the kitchen that should be kept from the stove and shaken once a month to mix the chemicals (see Figure 2). Become familiar with the extinguisherʼs operating instructions. Extinguishers must be recharged after each use.
Figure 3. ABC Fire Extinguisher. Stock image by JonasSanLuis
Under the home
Avoid storing ﬁre hazardous materials under the house, such as gasoline or paint supplies. Store ﬂammable liquids in a cool, well-ventilated place away from the home. In addition, never skirt or insulate the ﬂoors of your home with tarpaper or straw bales since these materials dry out and catch ﬁre easily. Areas under your home should also be dry and free of all materials that decay such as grass, roots, twigs, and wood. If the space under the home is to be enclosed with skirting or other material, the skirting shall be ventilated and a ground vapor retardant of 6 mil rated polyethylene sheeting or equivalent should be installed. Venting shall be provided for the crawl space as required by the latest publication of NCSBCS/ANSI_A225.1. The vapor barrier should cover the entire area under the home and overlap at least 12 inches at the joints.
Always have an electrician examine the wiring in your home to determine if the electrical system is adequate. Be aware that water heaters, dryers, ranges, and air conditioners require a 150-amp circuit breaker. Air conditioners may require special circuitry since they can drain power.
Remember, overheated outlets, switches, fuse or panel boxes, and overloaded circuits can cause ﬁres. Other trouble indicators are the smell of burnt plastic or dimming or ﬂickering lights.
Mobile homes constructed between 1968 and 1972 are likely to have aluminum wiring that has a tendency to over-heat. Resistance along the wiring arching at terminal connections can start a ﬁre by igniting insulated materials. Make sure the wire is heavy enough. Use a 14-gauge copper wire for 15-amp circuits. Also, determine if a metal shield protects the wiring as it crosses wall studs and whether the wiring is copper or aluminum.
Itʼs important to know your cords. The misuse of cords and heating appliances can also cause electrical ﬁres. Always use proper cords with any appliance and avoid running cords under a rug. A heavy-duty cord has a three-wire, three-pronged plug that is weatherproof and grounded (see Figure 4). Heater cords have heat-resistant coverings and adequate wire for heaters and small appliances (see Figure 5). Lamp cords have smaller wiring and lighter covering (see Figure 6).
Keep heaters out of trafﬁc areas, such as halls and doorways, and away from walls, furniture, drapes, children, and pets. (Heat-producing appliances and refrigeration appliances except ranges and ovens shall be of the vented type and vented to the outside as stated in 3280.707(b) of the Manufactured Home Construction Safety Standards).
WARNING: Class C or all-purpose ABC fire extinguishers should be used on electrical fires. Never use water.
It is urgent to have your entire electrical system in your manufactured house grounded directly to a ground wire that is attached to a ground rod driven at least 8 feet in the earth. Exposed or damaged wire can electrify the metal siding.
Use a ground fault interrupter (GFI) in bathrooms, laundry rooms, or outside where water can come in contact with electrical equipment. Cut off currents instantly if there is an electrical short in the ground or water.
Manufactured home dwellers, like standard home dwellers, must always be prepared for a ﬁre. Smoke detectors should be placed in the hallway communicating between the living and ﬁrst bedroom area. One smoke detector should protect each bedroom in used manufactured homes where common use areas, such as a kitchen or dining rooms, separate bedroom areas. Install only Underwriters Laboratory-labeled (UL) detectors and install according to instructions (Sloan, 1975).
Equally important is determining how to escape a ﬁre once it is detected because house ﬁres cause deadly fumes to rise. Plan and practice an escape route for the family. Check your windows often to be sure they move freely. Use a chair if necessary during an emergency to break the windows open in the event of a ﬁre or emergency.
Manufactured housingʼs affordability and convenience can meet the needs of the owner who is willing to become familiar with manufacturing housing safety and reap the rewards of a quality of life similar to that in a conventional home.
Alabama Cooperative Extension System Home Economic/Family Living (1982). H.E.: Housing Fact Sheet (HE-489). [Brochure]. Auburn, AL. St. John, M. & Speakman, G.
Figure 1: Manufactured Housing Statutory Law Rules & Regulations, 2004.
Figure 2: Foremost Insurance Company, 2004. How to install tie-downs and anchors.
My Great Home. Retrieved on August 23, 2004, from http://www.mygreathome.com/ﬁx-it_guide/tiedowns.htm.
Figures 3-6: Sprott, Michael. Housing fact sheet. Cooperative Extension Service, Auburn University.
R&G Mobile Home Supply. Anchors and tie-down accessories. Vector Systems Kit for Concrete Application. Retrieved August 23, 2004, from http://www.randgsupply.com/Warehouse/SetUp/vectorsystems.htm.
Sloan, Jim. (2001). (4th ed.) Statutory laws. Alabama Manufactured Housing Commission, p.57.