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Panelization gives conventional builders a huge edge over their stick-building competitors by allowing a house to go from the foundation to being dried-in in 2-3 days or sometimes less. This process often takes several weeks with conventional stick framing. Exterior and interior finish work is performed in the usual manner with most systems.
Panelization began with stick-framing; the only difference was that the walls, floors, and roofs were stick-framed in the factory rather than in the field. Stick-Frame Panelization (SFP) is still very popular today because stick-framed walls are very familiar not only to the builders, but to their customers. The late 1970's saw the rise of re-conceived panelized construction. The Structural Insulated Panel system, or SIP, for short, was composed of two layers of plywood glued to a core of foam insulation. SIP panels are exceptionally strong and stiff even though they contain no rafters, joists, or studs, and typically have insulating values far in excess of a comparably-sized stick-framed wall or roof that is insulated with fiberglass batts. Recently, SIP panels themselves have been re-thought, except this time, it is a refinement rather than a reinvention. Fiber-reinforced cementitious siding has been used for years as the exterior cladding of buildings. Some clever inventor realized that not only was the material very strong (it is, after all, made mostly of concrete,) but it is also rot- and termite-proof. So they replaced the plywood skin of SIP panels with Fiber-Reinforced Cementitious sheets, creating a wall panel (the FRC-SIP) that can be dunked in water and will dry out just fine. Now, inventors around the world are reinventing panelized construction at such a pace that it is hard to keep up with all the innovations. Some use foam-and-steel panels that are sprayed with concrete to any thickness desired, creating a hardened exterior that can be stuccoed. Because it is sprayed on both sides with quick-drying, gunned-on concrete (gunite,) the foam is encased forever in the center of the wall, insulating the heavy thermal mass of the interior concrete layer. These are generically known as foam sandwich systems (FSS.) Some of the new foam-and-concrete systems reverse the arrangement, building walls quickly of very large foam blocks that create a permanent form into which to pour concrete that creates the structure of the wall. These Insulated Concrete Form, or ICF, Systems are technically not panelized systems because they do not construct walls of full-length panels, but they install almost as quickly as the panelized systems. Two other distinctions between concrete-in-the-middle (ICF) and concrete-on-the-edges (FSS) systems are: 1) FSS walls are much more resistant to mechanical damage such as being struck by a line drive or by a rock thrown out of a mower, while 2) ICF walls create a straighter finished surface because the stucco installer is finishing over factory-milled foam rather than field-applied gunite. So if you're looking for a very crisp wall, it's easier to do with ICF, but if you're looking for a very relaxed, organic-looking wall that looks as if it may be stuccoed over a natural stone structure, then that comes naturally to FSS. The Aerated Autoclaved Concrete (AAC) blocks are similar in size to the ICF blocks, except they are made of a concrete mix that is put into an oven (autoclave) and expands dramatically when it is fired, creating air bubbles throughout the block (aerated) that create serious insulation value. AAC blocks are solid; even though there are no cavities like you find in regular concrete blocks, they are both lighter and longer than ordinary block because of the aeration of the concrete. They can be cut with regular hand tools, and need no additional insulation. There undoubtedly will be new panelized systems developed in the near future; please let us know if you are aware of some. In particular, we want to know about systems that are able to be submerged every 25-30 years and dry out without damage.  Panel Systems
The following is a system developed by the Center for Applied Transect Studies in Miami:
SFP
Manufacturing plants across the country make SFP panels; they are so numerous that it is not feasible to list them all here. One source of information on local or regional panel manufacturers is Automated Builder Magazine:
Stick-Framed Panels SIP
SIP manufacturing plants are almost as numerous, and will not be listed here, either. Rather, check with the Structural Insulated Panel Association website, which lists all of the manufacturers and builders in your area:
Structural Insulated Panel FRC-SIP
One of the pioneers of the FRC-SIP is Homefront, which is the company that supplied the panels for Katrina Cottage II, Katrina Cottage V, and Katrina Cottage VI. Their website is located at:
Fiber-Reinforced Concrete Structural Insulated Panel FSS
FSS has been under development for several years, but early systems had the troublesome little detail of panels that must be cut to fit on the jobsite, creating veritable snowstorms of styrofoam debris for as long as houses are being framed. Needless to say, the required cleanup was an issue, as was the fact that the sales team was always battling the repeated question of "are you building this place out of drinking cups?" Recently, however, there has been one company that we are aware of that has solved all of the earlier problems with several improvements, including manufacturing all of the panels off-site so that they need only be assembled very quickly onsite before being shot with gunite. Green Sandwich Technologies' website is located at:
Foam Sandwich System ICF
As with SFP and SIP systems, there are numerous ICF manufacturers. The industry trade organization is the Insulating Concrete Form Association. Their website can be found at:
Insulated Concrete Forms AAC
Until a few years ago, there were only two principal AAC manufacturers in the USA. Today, there are several. Their trade organization, the Autoclaved Aerated Concrete Products Association, is located at:
Autoclaved Aerated Concrete |