Investing in the Future: Pulte's Switch to Panelization PATH Case Study

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A quality operator performs a visual check and stages trusses immediately after automated assembly. Interior steel wall "We also provide an interior steel wall," Runnels says. "Steel interior walls were chosen because they are light; they provide a straighter clean finish; and with the use of mechanical fasteners like self-tapping screws in steel, nail pops are virtually eliminated. "We manufacture two walls at this time: 20-gauge (033-mill) for bearing walls and 22-gauge (027-mill) interior non-bearing for our usual 9'1" first-floor wall system and 8'1" second-floor wall system. Both have a high yield strength of 33,000 psi and a G-60 galvanized coating. "The G-60 coating is a standard for us because we know the longevity is greater. There have been issues with lower galvanized coatings that may have come in contact with masonry, in the basement for instance. G-60 is recommended by the American Iron and Steel Institute and the Steel Framing Alliance to minimize corrosion." Whole-house thinking "We look at the house as a system. We want to make everything work together — to simplify and speed up construction, and for better living," says Runnels. "For example, we design the floor system to be able to handle our lateral pressure loads, so we can backfill the foundation a lot quicker. There have been many cases in the Mid-Atlantic area where lateral pressure caused foundation walls to cave in. So code officials are requiring a lot of additional things to be done to the foundation walls before they can get backfilled. "And framers don't like building over open digs anyway. But with our system, our decks are in panels, so they can be rolled out quickly. Within an hour or two, you can have the first floor deck on. In a couple more hours, you can have the bolting done, and therefore the shear diaphragm in the floor can handle the lateral pressure to the walls from the backfilled dirt." Installation: quick and easy "We manufacture and ship wall panels that are up to 36 feet long and deck panels that are up to 45 feet long," Runnels says. "With long panels, the installer installs fewer pieces in the field, so he has fewer connections and alignment problems to deal with." "For small houses, we can install the pre-cast concrete foundation, install our floor system to support it, and backfill in a 10-hour day. Larger homes [5,000 to 6,000 square feet] will take us about a day to lay the foundation walls, and another day to clean up and install the deck. "For the entire process, we leave a 23-day window from the day we start to stake out and dig to the day we turn the house over to the mechanical contractors. We generally take an average of 19 days, based on the last six months of homes built. That's getting it all under the roof. The speed minimizes weather-related problems because building components are less exposed, which in turn gives us a better finished product." Lessons learned Early contractor trade education and integration is critical to success. Educate code officials early for easiest acceptance. Use whole-house thinking to maximize benefits. Insulate the foundation with rigid foam on the exterior for optimal performance and to prevent condensation. Use galvanized G-60 coating on steel. Installation crew: lean and speedy Installation costs are much lower because a smaller, less-skilled crew assembles the house more quickly. "We no longer need a large crew of carpenters," says Runnels. "We've done time studies that compared crew size, from four-man crews to eight-man crews, and we've narrowed it down so that the best size crew is five people. Before, you had a massive group of carpenters; now, you only need one carpenter and four installers. The carpenter is there only to manage the crew for any building that needs to take place inside the house. "We do a lot of training of the crews so they are able to adapt to this particular system. It does take them some time to learn how to install it. We usually allow framers five to six houses to be able to get up to par." PREVIOUS  1 | 2 | 3 | 4 | 5 | 6  NEXT