Recently installed HUD-code manufactured housing in the Pacific Northwest region of the United States has been tested for air leakage characteristics. The tests were done to establish a database of air leakage under current manufacturing and installation practice. Test results will help establish the potential for future energy savings through air leakage control programs when applied to manufactured housing.
Average leakage rates for double-wide manufactured homes were found to be 8.40 air changes per hour (ACH) at 50 Pa pressure differential and are predicted by the LBL model to be 0.50 ACH under natural atmospheric conditions. These averages are based on 93 homes tested for air leakage with the blower-door or fan depressurization technique. The estimated coefficient of variation (COV) of the 50 Pa leakage rate was 0.23. Nineteen different manufacturer's homes were tested.
Twelve of the leakiest homes were “house doctored” for air leakage control. These homes averaged 11.75 ACH at 50 Pa before house doctoring, and 9.34 ACH after the retrofit work. The homes improved an average of 19.5%. The retrofit job took 3.5 h per home, with an average expenditure (including labor) of $200 (U.S.).