A Better Manufactured Home?

A reader writes The Green Guide:

I have been an avid reader of The Green Guide for about a year now and find it so helpful! I am currently in a tough situation and my only option is to move into a manufactured home on land my parents own. I have long despised these types of homes as an environmental nightmare and health hazard. I have two toddlers and am just wrought with anxiety over their health and well-being in our new home.

I am hoping you might be able to give me some information to help minimize the health risks. Are there certain manufactured homes with less off-gassing (esp. formaldehyde) than others? Are some better environmentally than others? I want to do what is best for my family and the planet. Please help!!!

(Oh, and my son has severe food allergies which will progress to environmental allergies so I am really concerned about him breathing toxic air!) What can I do to lessen his exposure? Are there any filters that remove formaldehyde from the air?? I can't find information anywhere about these types of homes and their health/environmental impact.

The Green Guide Responds:

Unfortunately, we know of no manufactured homes out there that we can recommend, though it's possible you can retrofit your manufactured home to improve its air quality somewhat. John Bower of the Healthy House Institute had nothing good to say about manufactured homes: he told us that every one he knows of offgasses a number of VOCs, including formaldehyde, and that manufactured homes "usually have no ventilation at all." And the Leadership in Energy and Environmental Design green-building rating system does not include manufactured homes.

Why are manufactured homes so potentially hazardous? They contain a number of sealants and adhesives to keep the structure airtight for insulation purposes. Further, they use a good deal of resinous material, including acrylics, plastics, and large amounts of particleboard, all of which can offgas. VOCs plus a small, poorly ventilated space are an unhealthy recipe. The industry has changed particleboard formulations and improved ventilation, but Bower didn't know of a manufactured home worth recommending.

Paul Novack of Environmental Construction Outfitters, who's dealt with customers who already own a manufactured home, had a different take. He says he's performed retrofitting and renovations that have significantly alleviated air-quality concerns; he said large improvements can be made in the ventilation, paint, insulation, carpet, finish, and so on. Consult a private contractor after the fact, or, a better option, ask the manufacturer before buying the manufactured home whether you can substitute healthier materials for an added fee. Novack said that an ozone machine might knock down formaldehyde levels at first (but not while you're living there), howevere repainting and sealing surfaces and then using HEPA/carbon filter is much better. Novack adds that ozone machines can be harmful to some people. "You want to retard offgassing by sealing the walls and caulking all gaps as best you can," Novack says, adding "The key is getting the air circulation as best you can with air filters. Avoid carpeting if you can."

Bower disagreed with Novack on retrofitting: he said there's no easy way to retrofit manufactured homes to rid them of their VOCs. Adding ventilation or an ozone machine, or trying to bake the VOCs out by heating the house for an extended period, won't do the trick, he said. When two experts disagree, we remain agnostic. It seems likely that you can improve the air quality of your manufactured home, but perhaps not to an entirely acceptable level. Do keep in mind that any retrofitting you do will drive up the house's cost, lessening the savings from a cleanly built conventional house.

The Log Cabin Alternative

There are other options out there if you think you can't afford a conventional house, though it depends on your local climate and on the amount and characteristics of the land you have. In his Complete Guide to Building Log Homes (Sterling, $19.95), Monte Burch writes that the materials for a log cabin can cost as little as $1,000. (The cost goes up, of course, if you buy a kit or use a construction company, but it still is generally much cheaper than a regular home.) If you want to get even more traditional, you can look into the weather-tight circular platform tents known as yurts, originally used by Central Asian nomads. If you go through a manufacturer like Pacific Yurts (www.yurts.com), base prices range from $3,950 for a 12' diameter yurt to $8,750 for 30'. Optional features can run you a few thousand more, and then there's another few thousand for heating and the wooden flooring. For yurts, cabins, teepees (or tipis), and other alternative homes, there are plenty of books with much more detailed information—enough, in fact, to build your own if you're handy, or to guide a contractor if you're not. Look for Burch's book, David Pearson's Circle Houses, (Chelsea Green, $16.95) B. Allen Mackie's The Owner-Built Log House (Firefly, $24.95) and Log House Plans (Firefly, $24.95), and Paul King's The Complete Yurt Handbook. (Eco-Logic, $21.95)

But don't think that any alternative home is a magic bullet. Says Bower, "Things that go inside the structure are what's important"—finishing materials like cabinets and floor covering, far more so than the structure itself. Shop around: a conventional house might not end up costing much more than a manufactured home. (And is a cheap home that creates health problems—and medical bills—actually cheap?) With a conventional home, you'll be able to control the materials used in it, and to make sure it's healthy.