Air of Importance. A Study of Air Distribution Systems in Manufactured Homes

摘要

One has only to look at the statistics to see how important it is to consider211u001emanufactured housing in any residential energy research. Twenty percent of 211u001eexisting single-family homes in the United States are manufactured, and 25 211u001epercent of new single-family homes built last year were factory-built. In North 211u001eCarolina, the leading state for manufactured-home shipments, 40 percent of new 211u001ehomes last year were manufactured. Sponsored residential energy research has 211u001eadvanced the understanding of building systems in general, but this research is 211u001enot always transferable from site-built to factory-built housing. The scarcity of 211u001earticles in the literature dealing with new manufactured homes demonstrates the 211u001edisproportionate level of research investment being spent in this burgeoning home 211u001econstruction approach. The small amount of manufactured housing research that 211u001edoes exist has recently focused mainly on ways to improve the thermal envelope. 211u001eThis led, in part, to an increase in the thermal requirements for manufactured 211u001ehomes in the recent changes to the HUD Standards (October, 1994). In the last 211u001eseveral years, building scientists across the country have been quantifying the 211u001econtribution made by air distribution systems to building efficiency loss in site-211u001ebuilt homes. Estimates vary, but the average duct system appears to reduce 211u001eoverall system efficiency by 20 to 40 percent. This efficiency loss can have a 211u001emultiplying effect with air-flow sensitive, compressor-based space conditioning 211u001esystems such as air conditioners and heat pumps. Meanwhile, air distribution 211u001esystems in new manufactured homes have received very little attention. This study 211u001eis a step forward in trying to better understand air distribution in manufactured 211u001ehomes and their affect on overall system performance.