For 175 years, construction of residential homes has employed ‘stick construction.’ Even if you’re not a builder, you’d recognize it on sight. 2 x 4 framing with 16-inch on center studs, double top plates, and triple stud corners.
Every contractor in the game has built this way since forever. Imagine a blue collar movie starring Kevin Bacon or Bruce Willis with a half finished house frame. That’s stick construction or platform framing.
Starting in the energy crisis 70′s other building approaches have been creeping onto the scene. SIPs, ICF walls, double stud walls and advanced framing techniques are all nipping at standard stick construction heels. As building code begins to raise R-value standards and account for air leakage and thermal bridging, these approaches are becoming more common.
What is Advanced Framing Techniques
Advancing Framing Technique is a building approach that reduces the amount of wood used in construction. In theory, homes can be built faster (less wood), save money (less wood) and lose less heat due to thermal briding (less wood). Tastes great! Less wood! So what is it!
Advanced framing techniques safely reduce the amount of wood studs used in the framing. Advanced framing techniques borrows a concept from old construction, that of inline framing. That means all the wall studs and joists are in alignment, strengthening the frame. The intrinsic greater strength allows us to eliminate redundant framing elements, saving money, reducing waste and wood usage.
Walls – In standard construction, walls are 2 x 4 studs spaced 16 inches on center. Advanced framing uses 2 x 6 studs framed 24 inches on center. The 2 x 6 studs are stronger, allow more insulation in the cavity and reducing thermal bridging.
Floors – Traditional building uses 2 x 8 floor joists spaced at 16 inches. Advanced Framing uses engineered wood I-joists spaced at 24 inches. The I-joist are manufactured from waste wood and are straighter and stronger than dimensional lumber. The I-joists line up with the wall studs, strengthening the frame.
Corners – Three stud corners are the norm, adding an extra stud to hang drywall. This is replaced with a two stud corner and drywall clips. This reduces thermal bridging and eliminates an uninsulated void.
Windows – Windows are typically framed with king studs on either side, jack studs around the rough hole and cripple studs top and bottom to ensure sufficient thermal bridging. Advanced framing technique eliminates the non-load bearing jack and cripple studs.
Opening Header – An extra stud called a header is included over window and door framing. On non-load bearing framing, this is replaced with a single stud.
Wall Top Plate – The top plate being a structural load bearing member is doubled up in standard framing. In advanced framing, this is replaced with a single stud and a steel connector plate.
Interior Walls – Normally interior walls are constructed the same as the exterior walls. With advanced framing, the interior walls are 2 x 4s but still spaced 24 inches. As the walls are non-load bearing, they are secured with non-structural connector plates.
Advanced Framing Techniques – Advantages
Whew. That took a little while. So what are the advantages of leaving that much wood out of your house?
Like I alluded to earlier, the construction can cost less since you’re reducing the materials used so significantly. The 24″ wall cavities allow electricians and plumbers much more space to work.
Reducing the amount of wood in the wall frame reduces thermal bridging and the deeper wall cavity allows for more insulation and the effective wall R-value will be higher.
Wait … let me get this straight. It’s faster and less expensive to build and saves energy. Usually we can hit 2 out of 3, but not 3 out of 3.
Advanced Framing Techniques – Disadvantages
Advanced framing techniques are so great, there must be some big negative holding it back. And … not really though one is a doozy (that ought to be an energy auditor’s motto … there’s always a doozy problem).
Most contractors aren’t experienced with advanced framing techniques (though most are aware). And experience is essential to the speed and value of this approach.
There are other concerns out there but they are largely unfounded.
Some folks fear reducing the wood used so significantly will weaken the building frame. The opposite is actually true. Using in line construction, 2 x 6 studs and engineered I-beam studs actually strengthen the frame. Another fear is that this framing doesn’t meet building code. However, building codes do allow advanced framing.
The biggest question folks have is that drywall is insufficiently well supported, causing bowing and buckling drywall panels. Not only is this not true with properly installed panels and clips, the floating corners reduce dry wall cracking as the wood framing moves over time.
Advanced Framing Techniques are one of a new breed of construction approaches. Installed by an experienced crew, it can save money, energy, time and reduce waste.