Re-Thinking Framing Practices to Save Materials, Labor and Energy
By Ken Harward
Vice President - Construction Science Division Burgess Construction Consultants, Inc.
In times past, the quality of wood-frame structures was often judged by how much lumber was used in the framing process. If a structure was built with 16” stud spacing throughout, engineered wood sheathing on all exterior walls, double studs under single member load points, extra bracing and so on, that home was often more desirable to the prospective homebuyer. While the quantity of lumber may have been the benchmark of quality in the days of yesteryear, valuing a modern structure in this manner would be somewhat of an unbalanced judgment. With construction material and energy prices on the rise, it behooves us to rethink our methodology and make adjustments that make sense with regard to structural integrity, material costs and energy efficiency combined.
Structural integrity of a wood-frame structure is paramount to contractors, code officials, and engineers alike; yet it is still possible for many of us to reduce the amount of lumber used and satisfy the requirement of good building practice as well as those of the International Building Code (IBC) and International Residential Code (IRC). Advanced Framing and Optimum Value Engineering are good examples of saving and conserving opportunities, but these framing methods are not as feasible for some builders as for others. What may be of significance to one builder may be insignificant to the next due to regional differences or the particular product they are building. Nonetheless, there is something that we can all do to reduce unnecessary material and labor. As always, each builder/contractor should make informed choices and consult the local jurisdiction and engineer of record before changing a framing practice.
The questions to ask ourselves about current framing practices are: 1) Why we do things the way we do them? 2) Are they out of tradition or for a beneficial or required purpose? What was required or common practice ten years ago may no longer be valid. The following practices are worth exploring and could save hard costs and/or enhance the energy performance of the structure.
Hip, ridge, and valley braces occurring above a top plate have traditionally been supported below the top plate with double studs. Although it may be advisable to locate the brace on the top plate directly over a stud, doubling the stud is not a requirement found in the IRC.
Fireblocking in areas of no consequence is common at art niche shelves, between studs at 10' above floor level, along the sides of certain stairways, and so on. Fireblocking is indicated by the 2009 IRC as for the purpose “to cut off all concealed draft openings (both vertical and horizontal) and to form an effective fire barrier between
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stories, and between a top story and the roof space.” While the code is subject to interpretation, it is worth the effort to read and understand the intent of the code and gain the perspective of the jurisdiction with regard to fireblocking. Many framers continue to practice fireblocking techniques from many years ago which are simply not logical nor supported by the code.
Load-bearing headers in non-load bearing walls can often be replaced with flat 2x4 nailers to eliminate conventional built-up headers.
Open (2-stud) corners in exterior walls can be used to save studs and allow insulation to fill the corner, increasing the energy performance of the dwelling.
Ladder blocking can be used to attach interior walls intersecting with exterior walls as this saves studs and allows insulation to fill the area previously occupied by framing.
Eliminating material misuse/overages is not a new problem, yet it continues to be a widespread concern. When the wrong length lumber is cut-to-fit (as evidenced on the job by 24” or greater off-fall) or a more expensive grade of material is substituted for a lesser grade, someone pays the price. In the case of excess material, the supplier should be promptly notified in writing with a pre-determined time allowance to pick the material up.
Multi-ply headers and beams nailed together from both sides is a common practice. If this is not required by the engineer of record for particular beams, then it is not necessary as the IRC
BEST PRACTICES
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