Off-Site Manufacturing Could Play a Larger Part in the Building Renaissance

Danny Small

Danny Small

Danny Small is Manager, Building Science Development for CertainTeed Corporation

Lately I’ve been revisiting the benefits of modular or prefabricated home construction, otherwise known as off-site manufacturing (“OSM”). There are several advantages to this method of construction that could be attractive to consumers looking to build a custom home.

This isn’t your daddy’s mobile home we’re talking about here.  The traditional manufactured (“mobile “) home is built to special Housing and Urban Development (HUD) building codes.  These homes are extremely simple, lower-end homes constructed in one or two pieces on a steel frame.

Today’s modular home can be beautiful, complex, exquisitely detailed and of the highest quality.  It’s built in modules or panels, in a clean, climate-controlled facility to meet (and often exceed) standard building codes for the area where the home will be finished.   The modules or panels are then shipped to the construction site, where they are permanently assembled on a full foundation, and the final details are finished.  Once completed, these homes are indistinguishable from site-built homes.  For some examples, check out Haven Custom Homes’ gallery.

While off-site construction has been around for decades, most of the earlier homes fell into that category of mobile (HUD-code) homes.  However, the move toward more sustainable, energy-efficient, healthy homes creates compelling reasons to look at modular as a truly viable method for all construction.

Some of the advantages of offsite construction are:

  • Construction can begin while foundation work is done, reducing the overall build time by several weeks.
  • Because building is done indoors in a climate-controlled facility, there are no weather delays.  Crews can work year round with no problem.
  • The home is built dry and clean because the wood is not subjected to dampness or dirt.  This could make for a healthier house.
  • Greater accuracy in cutting is possible because precision equipment can be utilized.
  • Lower costs because of consistency with crews and minimal lost time.  An off-site built home can cost up to 15-20 percent less than the same home built on-site. (Source: NAHB)  Savings for commercial construction can be much higher.
  • Very low waste.  Just about all remnants can be re-used for other projects.  This enables contractors to purchase more wisely.
  • Off-site manufacturers can ship up to 500 miles from their factory.
  • The building envelope is fully customizable, enabling increased energy efficiency in the wall and ceiling systems, as well as design features that meet the needs of the occupants.
  • Modular building, especially in commercial, enables easy expansion to buildings when needed.

Although off-site construction currently accounts for only two percent of construction in the U.S., the industry is gaining popularity.  In Europe, especially countries like Sweden, this type of construction is on the rise and accounts for up to 40 percent of new construction. 

If you are considering building a new home, a vacation home or a small office, do a cost comparison for on-site versus off-site construction.  You may be surprised by what you find.