“Advanced Framing” – Green Building Target!Mar 21 2017 · 0 comments · Nishkian Chamberlain, Sustainable, Wood Frame ·0
The demand for affordable housing in urban areas is increasing as rent prices skyrocket. Many developers are now required to include a percentage of affordable housing units to obtain approvals for their new multi-family construction projects. Additionally, affordable housing projects that wish to access alternate funding sources are often required to meet various green building requirements.
Recently, Nishkian Chamberlain began work on a new affordable housing project in Ventura, California. The project is unique in that it is entirely comprised of affordable housing apartment units. In order to receive some state and federal funding, the project is required to meet several green building targets. One such target is the use of “Advanced Framing”.
In short, Advanced Framing is energy and material-efficient wood framing. Conventional wood framing, typically used for many years, includes many structural redundancies (double top plates, three-stud corners, multiple jack studs, double or triple headers, etc.). The goal of Advanced Framing is to eliminate unnecessary redundancies and achieve savings in material usage while also taking advantage of opportunities for increased energy efficiency.
There are various techniques commonly used in Advanced Framing. Which technique(s) are used is determined on a project-to-project basis. One technique applied to a recent project was the use of engineered wood floor joists. Using engineered wood floor joists allowed larger joists spans and wider joist spacing, leading to savings in materials, increased construction efficiency, and reduced construction costs. It is critical for the structural engineer on the project to coordinate joist depths, which may be larger due to the increased spans and spacing, with the architect and MEP early on in the project to minimize conflicts and rework later on.
Additionally, for this project, the increased floor joist spacing affected the design of the floor sheathing. A larger span rating was required, and serviceability characteristics such as floor vibration were investigated. It was recommended to use a thicker floor sheathing than what we use for Conventional Framing to achieve the required span rating, reduce vibrations and increase the perceived stiffness of the floor.
In addition to using engineered wood floor joists, other Advanced Framing techniques include:
- Using 2×6 studs where possible to increase cavity insulation depth.
- Increasing wall stud spacing from 16” o.c. to 24” o.c. to reduce material usage.
- Implementing two-stud or insulated three-stud corners (also known as California corners, see Figure 1) to reduce the quantity of framing members and/or increase cavity insulation space.
- Using energy efficient headers and reducing framing around openings.
- Eliminating double top plates. However, all the vertical supporting elements must be coordinated to stack up on each other.
- Using “Energy Heel” roof trusses to increase cavity insulation space (Figure 2).
These techniques can be mixed and matched to accommodate the unique aspects of each project while still achieving the targeted green building requirements.
In conclusion, the demand for affordable housing is increasing, especially in high density urban areas where housing is in short supply and rents are high. Affordable housing projects often target green building requirements such as the use of Advanced Framing techniques to obtain State and Federal funding. Advanced Framing techniques can be used individually or in combination to achieve the desired green building criteria.
If you are interested in finding out how using Advanced Framing techniques can benefit your next project, Nishkian Chamberlain has significant experience in this technique and would be happy to discuss your construction and development needs. You may contact Craig Chamberlain at CChamberlain@nishkian.com or (310) 853-7180.