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After years of waiting, the U.S. Department of Housing and Urban Development (HUD) has proposed new energy conservation standards for manufactured homes. In some respects, the proposed standards, mandated by Congress back in 1987, may be imitating life in the conservation world rather than shaping it. Consumer demand and new technologies have already spurred construction of factory-built homes that exceed the current standards, effective in 1976, and some utility incentive programs have established efficiency levels higher than HUD's new proposed standards.

Under the proposed HUD standards, the maximum thermal transmission coefficient, expressed as a U-value, would be reduced for all areas of the country. At the same time, the existing three U- value zones would be changed to four zones with different boundaries (see Fig. 1).

HUD contracted with Pacific Northwest Laboratory (PNL) to develop the revisions to the energy conservation requirements to the Federal Manufactured Home Construction and Safety Standards, and PNL's proposed revisions were used almost without change as HUD's published proposed rule. According to Craig Conner of PNL, under the current standard the national average U-value is 0.145, and the proposed standard would lower the national average U-value to 0.098. He estimates that current building practices already achieve a national average U-value of 0.125-0.120.

Generally, lower U-values are possible through the use of more insulation in ceilings, walls, and floors, and the installation of more thermally efficient windows. However, as Conner points out, "The standard doesn't specify how you achieve the U-value; it only requires that you meet the overall value, and any reasonable combination of factors is possible." PNL decided not to recommend lower infiltration rates in the new measures because "new manufactured homes are relatively airtight..[and] very low infiltration rates can have significant negative impacts on occupant health (1)."

The 1987 legislation requires that the energy conservation standards shall be cost-effective and designed to ensure the lowest construction and operating costs for the consumer over the life of the home. Conner estimates that the proposed standards will increase the national average cost to the consumer by $10 per month in mortgage payments, compared with the current standards, but will result in a monthly benefit of $18 per month in energy savings.

Some experts are concerned that the proposed HUD standard may not provide much improvement for Florida, which would comprise the new Zone 1 along with Hawaii. Subrato Chandra of the Florida Solar Energy Center notes that in Florida, the cooling load is much greater than heating, so strategies should focus on reducing the cooling load. A home with a low U-value may not provide adequate energy savings, because the U-value only takes into account part of the cooling load. According to Chandra, "The U-value standard doesn't account for passive cooling load control measures, such as ceiling fans and window shading, and these cooling strategies should be given credit when calculating cooling load." Chandra says he recommended that the Florida Energy Code be used as one of the alternative energy calculation methods allowed under the proposed HUD ruling.

In the Pacific Northwest, after years of frustration and delays waiting for new HUD standards, utilities and energy offices have created their own program for increasing energy efficiency in manufactured homes. The issue is a pressing one there because nearly 30% of all electrically heated homes in the Northwest are constructed in factories rather than built on site. Eighteen companies build about 11,000 manufactured homes annually for buyers in Oregon, Washington, Idaho, and Montana. Ninety percent of the region's manufactured homes are electrically heated.

Although the region has had a Super Good Cents program since 1984 that has exceeded HUD standards, a new incentive program, known as the Manufactured Housing Acquisition Program, took effect in April 1992 with the support and cooperation of the Northwest Power Planning Council, Bonneville Power Administration (BPA), state energy offices, electric utilities, and the manufacturers.

During the next four years, BPA and the region's utilities will invest $120 million by paying manufacturers the extra $2,500 it costs to add efficiency measures to each new home. Specifications call for ceiling insulation of R-49 (attic) or R-38 (vault), R-21 for walls, R-33 for floors, windows (dual glaze, vinyl frame, argon-filled low-E) rated at R-3, and doors at R-5. Under the Manufactured Housing Acquisition Program, Northwest homes will have a U-value of 0.053, as compared with the proposed HUD standard of 0.079, and the current HUD standard of 0.126. Estimated heating energy for Manufactured Housing Aquisition Program homes will be 4,000Ð 8,500 kWh/yr as compared with current HUD code standards of 13,800Ð23,500 kWh/yr. Note that manufactured homes in the Northwest have exceeded HUD standards since the early 1980s, prior to the Super Good Cents and Manufactured Housing Aquisition programs.

Northwest utilities, BPA, and the Northwest Power Planning Council have questioned the proposed HUD standards on the grounds that they overlook more recent research and cheaper insulation that could improve HUD's analysis and thermal standards. With higher standards, BPA could lower or eliminate manufacturer incentives.

On the other hand, the Manufactured Housing Institute opposes HUD's proposed levels and suggests that the levels and geographic zones should be the same as those proposed in June 1989 by the Manufactured Home Construction and Safety Standards Consensus Committee (see Fig. 1). Frank Walker of the Manufactured Housing Acquisition Program, argues that the HUD proposal does not follow the Congressional directive to produce energy requirements that are cost-effective to the homeowner, and that it disagrees with HUD's assumptions for calculating life-cycle costs based on the average lifespan of the home, rather than by the occupancy of the homebuyer.

The manufactured housing industry is particularly concerned about HUD's proposed Zone 4 which includes all Northwest, north central and Northeast states with the lowest required U-value of 0.079. Builders feel that it will increase construction costs far beyond HUD estimates and could seriously damage sales in this region. But not all builders feel this way. Tom Eckman at Northwest Power Planning Council notes that the 18 regional manufacturers involved in the program in the Northwest "are sitting on the sidelines on this one."

A date for establishment of final standards is difficult to predict. Even if the public comments are incorporated and a final rule is published in the Federal Register by early 1993, it would be late 1993 before they become law. Recently a new kind of potential delay has appeared. The standards are subject to the approval of the White House's Office of Management and Budget as well as Vice President Quayle's Council on Competitiveness, at a time when the Bush Administration has instituted moratoriums on new federal regulations for some agencies. The outstanding question remains: how many sub-standard factory-built homes will hit the market-and consumers' pocket books-while the new standards are held in abeyance.

-Ted Rieger

Ted Rieger is a freelance writer for trade publications and specializes in energy topics. He lives in Sacramento, Calif.