Have you ever stopped to think about the energy efficiency of a doublewide?  DOE is about to do just that, having initiated a rulemaking to develop mandatory standards for manufactured homes (basically a building code) under order from Congress to finish by 2011.  I just drafted and submitted NRDC’s comments to the docket.

Most people haven’t given the issue any thought, but the inefficiency of manufactured housing is something that really sets me off.  Like pound my head into a desk, scream into a pillow frustrated.

Why?  Well, basically these homes can be terribly inefficient (and in some cases just terrible, remember the toxic FEMA trailers?).  They commit the owner (who generally is low or fixed income and can least afford it) to higher energy bills and – this is the really frustrating part for this engineer – they have the potential to be more energy efficient than traditional homes!  Manufactured homes could be (and should be) the frontier for efficient design! 

If that doesn’t quite get you going then consider this – a manufactured home can come off the assembly line today and immediately be eligible for weatherization through the Weatherization Assistance Program.  That means that the government would be paying to retrofit this home to become more efficient when just months before it could have been done at the factory for pennies on the dollar.  I can’t think of a single reason why it is acceptable for new manufactured homes to be weatherization candidates because the code is not up to par.

And it’s not even close.  Manufactured homes use almost twice as much energy per square foot as single family homes according to DOE.  The average bill is around $1,600 per year, which over 30 years could equal the entire purchase price of the home!  But it certainly doesn’t have to be this way.

Manufacturing a home has all kinds of advantages over building it on site.  All work is done by the same folks in a controlled area where the quality can be inspected at any point.  All the insulation can get to where it needs to go and all the walls can be sealed tight.  No cutting holes to make pipes or ducts fit around unplanned obstacles.  And no question about code compliance.  Plus manufacturers can use volume purchasing and procurement to get materials, appliances, and equipment at lower prices than site builders. 

So a manufactured home could be more efficient than site-built homes, but how much?  Tough question but DOE is going to work on answering it by developing a new code that is much more efficient and makes money over the lifetime of the home. 

It shouldn’t end there, however.  We all want to get to zero energy homes and at a large scale, but what makes us think that super efficient zero energy homes will be built on site with hammers and nails?  Shouldn’t we explore the potential of manufactured homes to get us towards zero energy?  Shouldn’t we at least stop saddling those who can least afford with ridiculous energy bills that keep them in dire financial straights?  Clearly I rant, but hopefully DOE is thinking the same way and moves forward aggressively on manufactured home efficiency.