Modular building has gotten a steady flow of ink in recent years, thanks, in no small part, to the consumer shelter magazine dwell, which has made the construction system its darling, and Web sites such as A squadron of young-turk designers (Michelle Kaufmann, Charlie Lazor, Jennifer Siegal, Joe Tanney, Robert Luntz, and Rocio Romero, among many others) championing the technology has helped the process along as well. But the modular housing industry itself deserves the lion's share of the credit for the expansion of its business. One of the fastest-growing segments of the construction industry, modular housing production increased 48 percent from 1992 to 2002, the NAHB's Building Systems Councils says. Even now, the industry says the slowdown in the housing market has not been as pronounced for them as it has been for stick builders. So what does any of this have to do with you? Everything, the modular industry says.

Surely you've heard the industry's sales pitch by now: lower costs, speedy construction, excellent craftsmanship, and quality building products in a controlled setting. Builders who use modular systems say you can believe the hype. But before you run out to your local supplier or modular home manufacturer, you need to do your homework. On the following pages is a list of important items you should know before you place that order for your first modular home. As always, the devil is in the details. Read these items, study them, then go forth with confidence.

1 FAMILIARIZE YOURSELF WITH THE MODULAR PROCESS. This may seem like a no-brainer, but it's important. Building a modular house is a different ball game from stick framing in a subdivision. The homes are built in a factory in programmed stages from flooring to finished product and then set in place at your jobsite. “Floor treatments, framing, insulation, drywall, roofing, windows, siding, cabinetry, plumbing, and lighting fixtures are all installed and completed by skilled craftsmen utilizing state-of-the-art production technology,” the Building Systems Councils' Web site says. “The home is then shipped, 90 percent complete, to the building site and assembled on a foundation.” This means you will have to assume a different, but no less important, role and fret about a different set of issues (more about these later).

2 ALL MODULAR MANUFACTURERS ARE NOT CREATED EQUAL. Finding a good modular manufacturer is not like throwing a brick in a crowd—unless your aim happens to be very good. Modular construction can be better than stick-built housing in principle—tight tolerances, controlled production, and all that—but the quality of modular houses varies from manufacturer to manufacturer just as much as site-built homes do, so you'll need to do some leg-work. “There are some high-quality companies out there doing really good work, but you have to find them,” says Joe Tanney, a principal at New York City–based Resolution: 4 Architecture, a firm that specializes in custom architecture, including custom modular homes. Clyde Kreider, sales manager at modular builder Clemleddy Construction in Hawley, Pa., agrees. “I've been burned in the past with bad modular and cheap products,” he says. Check the reputation of the modular manufacturer and ask to see some finished homes. If you can, ask a previous builder customer for a reference.

3 BUT IT'S NOT ONLY ABOUT THE FINISHED PRODUCT. How the house looks when it's done is fine enough, but your choice of manufacturer should depend on much more. “Choosing a modular manufacturer is a big decision for a builder,” says Jeremy Bertrand, executive director of the Building Systems Councils. “To determine the right company, a builder should consider a company's geographical reach, their range of designs offered, whether there are protected territories, marketing support, training offered, etc. A builder should not focus solely on how much a company can save them on price per square foot—these other issues are just as, if not more, important.”

4 THINK ABOUT THE SITE, PARTICULARLY THE FOUNDATION. On a conventional stick-frame home, you can easily make adjustments for foundations that aren't exactly plumb, level, or square. Because the modular house is built in a factory and brought to the site, you don't have this luxury. “The foundation has to be perfectly square to within a half inch,” says Vinnie Lanza, with Ringwood, N.J.–based Environmental Construction, a builder that does modular spec homes and some modular custom homes. “That is set in stone.” Lanza, who has done over 100 modular homes, says the site also needs to be level and cleared of trees and wires to accommodate a crane.

5 MODULAR MANUFACTURERS CAN DO A LOT MORE THAN THE TWO-BOX RANCH, BUT REMEMBER TO KEEP THE DESIGN (RELATIVELY) SIMPLE. You can design almost any type of modular house—from sleek Modernist shrines to quaint cottages and Mediterranean-inspired mansions—but just because you can design anything doesn't mean you should, especially if you're trying to save some dough and hit a deadline. “You should stay away from complicated roof designs and the like,” says Steve Scharnhorst, president and CEO of modular manufacturer Excel Homes in Liverpool, Pa. Though complicated designs are possible, he says they “eliminate the savings you achieve. You don't want to overcomplicate things.” Plus, complex designs will likely result in more site work and, thus, more time.

Nigel Maynard is a former senior editor with Builder magazine. 

Learn more about markets featured in this article: New York, NY.