|
MANUFACTURED HOUSING IN
NONMETROPOLITAN AREAS: © Housing Assistance Council, 1996 Permission is granted ONLY to nonprofit community-based organizations to reproduce and/or adapt this document, and only for their own use. Those concerned about the suitability of manufactured housing as decent, affordable shelter for rural residents often focus on a perception that manufactured homes are less safe and less durable than conventional homes. While current information indicates that some of the most egregious safety problems are seldom found in new manufactured homes, it is also clear that manufactured/mobile homes as a whole are not yet equivalent to conventional housing units. While the 1976 HUD Code did improve the quality of manufactured housing, available information indicates that not all post-Code units comply with the Code. In addition, very little information is available about rates of deterioration over time. It should be reiterated here that the potential errors inherent in sampling (see Appendix A) render uncertain the small percentages and the even smaller differences in percentages reported by the American Housing Survey with respect to housing quality. Quality Problems in Units Occupied in 1993 Physical Problems In 1993 nonmetro mobile homes generally experienced about the same rates of the severe and moderate physical problems measured by the American Housing Survey as other types of housing in nonmetro areas and as mobile homes in metro areas (Table 4).10 Similarly, the AHS reported the same proportion of other types of housing problems (e.g., water stoppage, flush toilet breakdowns, and sewage disposal breakdowns) for nonmetro mobile homes as for other types of housing in nonmetro areas and for metro mobile homes. Nonmetro mobile homes were slightly more likely to be crowded than nonmetro non-mobile units; the difference is probably attributable to the fact that non-mobile units tend to be larger than mobile homes. AHS information about equipment failures, equipment and plumbing, and selected repairs and improvements is provided in Appendix D, Tables 1-3. Other sources confirm that manufactured homes do experience certain physical problems, although it is not clear whether the rates of these problems are different in rural areas than in cities. Durability was an issue raised repeatedly before the National Commission on Manufactured Housing, and structural problems comprised the largest category of "nonconformances" to the HUD Code reported in 1988, 1989, and 1990 (the most recent years for which data is available), as noted by HUD's Manufactured Housing and Construction Standards Division in its most recent report to Congress. The nonconformances included defective doors, roof problems including leaks and sagging, warped or buckled floors and ceilings, and inoperative and leaky windows.11
Table 4.
Severe and Moderate Physical Housing Quality Problems
* Figures may not add to total because more than one category may apply to a unit, or because of rounding. While these findings mean that some homes still are not being constructed to the Code's requirements, at least some of these problems may be attributable to sources other than design flaws. One researcher compared "design requirements for live loads and deflections" in the HUD Code with the national standards for site-built housing developed by the Building Officials and Code Administrators. He found the requirements to be similar, and therefore believed it would be "reasonable" to expect the structural systems of manufactured and site-built homes "would have similar on-site structural performance and longevity." He concluded that there were "some significant differences in the technologies used for subassemblies of the structural system" because of technological innovations in the manufactured home industry and the requirements for manufactured homes to have features like permanent chassis, but did not draw conclusions about the effects of these technological differences on durability or safety.12 The apparent quality problems of manufactured homes could be attributable to manufacturers' quality control programs. HUD's report noted, for example, that "quality control in some manufactured housing plants does not realize its potential." 13 (More information about the regulatory system in place to control these problems is included in Appendix C.) Water Supply and Sewage Disposal Mobile homes in nonmetro areas relied on wells slightly more often than nonmetro non-mobile units (Table 5). While about two-thirds of nonmetro mobile homes obtained water from a public system or private company, less than one-third used a public sewage disposal system. Nonmetro mobile homes were significantly more likely than nonmetro non-mobile homes or suburban mobile homes to use septic tanks or cesspools. Their lower incidence of reliance on public water supply or sewage disposal could reflect their location in more remote areas, or in less wealthy areas, less likely to be served by such systems.
Table 5. Water Supply and Sewage Disposal
Overcrowding Nonmetro mobile homes were overcrowded more often than other nonmetro housing units, as shown in Table 6. Mobile homes in central cities were overcrowded more often than those in suburban and nonmetro places, consistent with a higher rate of overcrowding in all types of homes in central cities. Similarly, as illustrated in Figure 7, mobile homes made up a disproportionate segment of all overcrowded units in nonmetro areas: 25 percent, although they comprised only 13 percent of all occupied units.
The higher rate of overcrowding in mobile homes is not surprising. As previously noted (Table 1), the median family size in nonmetro areas was almost the same for both the households living in mobile homes (2.3 persons per room) and those occupying other types of housing structures (2.2 person per room); however, mobile homes tend to be smaller. In nonmetro areas, the median size of mobile homes was 926 square feet, only slightly more than half of the 1,702 square feet for other types of units. The 926 square-foot size reflects the predominance of single-wide units in nonmetro areas. (See Appendix B for definitions of single-wide and double-wide units.)
Table 6. Characteristics of Units' Size
Mobile homes also had fewer rooms -- a median of 4.8 -- than other homes in nonmetro areas, with a median size of 5.7 rooms. Changes Effected by HUD Code While the studies summarized below indicate that manufactured housing units built after the HUD Code went into effect in 1976 are in some respects of higher quality than units built earlier, available data does not indicate which nonmetro residents live in the older units or where they are located within nonmetro areas. American Housing Survey data can be used to compare "mobile homes" with conventional units but, as previously noted, the "mobile home" category includes pre-1976 units, travel trailers used as dwellings, and other non-"manufactured home" units, while it may omit some post-1976 manufactured homes. Therefore, available data does not permit comparisons of pre- and post-1976 units, or of other subcategories included within the "mobile home" category. The published AHS data does show that the median year in which nonmetro mobile homes were built was 1978, so over half the nonmetro mobile homes occupied in 1993 were built after 1976. Conversely, almost half the residents of nonmetro mobile homes lived in units fabricated before 1976, and therefore faced a greater risk of injury or property damage than residents of post-Code units. Anecdotal evidence suggests the lowest income families occupy the oldest and most decrepit units. A local organization in Wisconsin, for example, notes that "the poorer the family, the older the mobile home, the longer they live there and the worse the condition."14 Mobile homes tended to be newer than other nonmetro units: the median year other nonmetro units were built was 1960. This difference does not necessarily indicate that mobile homes were likely to be in better condition than other units, however, because the "useful life" of mobile homes may be shorter than that of non-mobile units. A 1995 study for the Manufactured Housing Institute found that new manufactured units, occupied year-found, have a life expectancy of approximately 55.8 years.15 In contrast, it has been suggested that properly maintained conventional housing could have a physical life of hundreds of years.16 (These figures could vary, of course, for both manufactured housing and conventional housing, based on the material of which they are constructed and the climate in which they are located.) The life expectancy of older manufactured homes, fabricated before current methods and technologies were available, can be assumed to be shorter. Indoor Air Quality Despite the Code-affected improvements summarized below, at least one set of problems seems to have worsened since 1976: as manufactured homes have been constructed more tightly to conserve energy, indoor-outdoor air flow has decreased.17 The ensuing reduction in ventilation leads to build-up of condensation indoors, which may result in warped paneling and mildew. In addition, reduced ventilation may create indoor air quality problems. For example, some of the materials used in manufactured homes emit formaldehyde, particularly when new. To improve air exchange, many manufacturers now provide mechanical ventilation as part of the heating/air conditioning systems in their homes, although such ventilation is not currently required by the HUD Code. Fire Safety Fire safety is one issue that has been measurably impacted by the HUD Code. Fire has been a particular concern with manufactured homes because of the flammability of some of the materials used to construct them, and because of the problems with escape from fire in older units. Homes built since 1976 to HUD Code standards have shown somewhat better fire safety records, although there has not been the steady decrease in the numbers of fires or deaths that might have been expected. Use of smoke detectors (required by the HUD Code) has had a marked effect in reducing the number of deaths and personal injuries from fire. Records show that some deaths and injuries occurred because the units lacked smoke detectors; since there is no evidence indicating that smoke detectors were not installed, these findings indicate that some residents have been removing or disabling the detectors. Increased use of gypsum board instead of paneling walls has slowed flame spread and helped to confine damage.18 According to the American Association of Retired Persons (AARP), "improved standards significantly reduced problems associated with inadequate flame-spread protection around kitchen ranges and cabinets, emergency egress, natural gas pipeline connectors, improper furnace installation, defective water heaters, and glass on closet doors."19 In addition, the rate of deaths by fire in post-1976 homes fell by 74 percent, and the fire injury rate by 34 percent, according to a study examining fires that occurred in the 1980-87 period. The study found, however, that some provisions of the HUD Code seemed more effective in improving fire safety than others; for example, fires in post-1976 homes were more likely to remain contained in the room of origin, but, contrary to Code requirements, half the post-Code homes involved in fires had no smoke detector.20 A 1986 study by the Foremost Insurance Company found fewer fires in units built after the 1976 Code. The published study did not report actual numbers, but stated that there were 1.2 fewer fires per 1,000 homes in post-Code units in comparison to the number of fires in pre-Code units (a 32 percent decrease in the number of total unit losses). This study also found that the chance of having a fire was twice as high for a site-built home (17.3 fires per 1,000 homes) than for a manufactured home (8.1 fires per thousand), but that the average dollar loss was greater from fires in manufactured homes. For the study, the country was divided into two territories based on similar characteristics. In the territory including most of the southern states (where more than half of all nonmetro manufactured homes were located), only 40 percent of manufactured homes were found in what were termed "fire protected areas" -- i.e., areas adequately served by firefighting equipment -- for underwriting purposes. The severity of manufactured home fires was greater in that territory. In the rest of the country, 69 percent of manufactured homes were located in fire protected areas, and average losses were smaller. In a rural area, the extra time it takes for fire equipment to arrive may result in a total loss of the unit.21 Winds and Floods In addition to fires, manufactured/mobile homes are particularly vulnerable to damage from hurricanes and tornadoes, even if built after the 1976 Code. In 1992, Hurricane Andrew destroyed 97 percent of the manufactured homes in Dade County, Florida, where only 11 percent of other single-family houses were destroyed and 43 percent of single-family homes sustained major damage. More than half of the mobile homes in Dade County had been built before 1976. Many of their anchoring systems failed.22 New wind standards went into effect in the HUD Code in July 1994; manufactured homes placed in high-risk hurricane areas now must be designed to withstand approximately 100 mile-per-hour winds.23 Andrew reached 120 mph, however, with gusts to 140 mph. In Louisiana, where Hurricane Andrew's winds were under 100 miles per hour, there was less damage even though many units were found to be improperly anchored. Flooding can cause another type of damage to which nonmetro manufactured homes are especially vulnerable. Riverine floods may involve slow water rises that can undermine or otherwise damage installation systems and cause anchors to fail. In addition, flash floods can involve strong lateral pressures on foundations or piers, and floating debris can cause further damage to the exterior. If water levels rise above floor level, interior damage to the structure can be extensive. In coastal areas, storm surges bring high tides and wave action that can be devastating. Some damage can be averted, at additional expense, by raised installations using properly designed fill and/or posts. The National Flood Insurance Program can insure against losses, but the program is available only to communities that agree to implement land use management to reduce losses. Not all communities choose to participate.24 Some wind and flood damage can be avoided by proper installation and tie-down (the anchoring or attachment to a permanent foundation) of units. These can be important issues -- the Commission heard testimony that 50 to 75 percent of all complaints about manufactured homes related to their installation25--but they are regulated and enforced in widely varying ways. The HUD Code does not include standards for storage or installation of manufactured homes, although it does require home designs to include manufacturer's instructions on how those activities should be performed. Thirty-one states have codes governing installation, some of which are based on a national voluntary standard developed by the American National Standards Institute (ANSI).26 Among the 36 states that have a HUD-approved State Administrative Agency handling enforcement, 24 states have tie-down laws and 18 have enforcement procedures.27 (Appendix C provides more details on the regulatory process for manufactured housing. These issues were considered by the Commission and therefore are not examined in detail in the present report.) The content and enforcement of these state codes is not consistent among states, and at least some of the state codes apply only to installation of new homes, not to used homes. In those states where local building inspectors are designated to inspect installation, they may be unfamiliar with the particular needs of manufactured houses. This may be especially true in small communities where inspectors do not specialize. Also, depending upon state laws, resold manufactured/mobile homes in rural areas may easily be missed by inspectors or inspection agencies. While it is clear that inadequate installation and tie-downs create housing quality problems, the proportion of problems caused during the transportation of the unit is unknown. The Commission received conflicting testimony on this point, and noted that it is difficult to determine whether transport actually caused a specific inadequacy in a given home, particularly if it is not discovered for years, as may be the case with structural problems.28 Damage from shock and vibration during transport may be exacerbated in remote areas. Long distances and poor roads can result in cumulative damage to the structure. Neither manufacturers nor retailers can be sure that all haulers follow procedures such as driving speed designed to minimize damage. While initial setup is often handled by retailers with some expertise, resale of houses may not involve retailers. Thus, expertise on moving a manufactured house may not be readily available or used.
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
