The Quick Green Blog - An Appraiser View

Resource efficiency begins at the design phase.  Key considerations are:

• Reduction in waste/scrap
• Reduction in use of old-growth lumber
• Reduction in transportation requirements
• Use of recycled/salvaged materials
• Use of enhanced framing materials/methods

Waste Management

A resource-efficient design incorporates materials to maximize function while optimizing the use of natural resources. In addition, resource efficiency reduces job-site waste and recycles generated waste where appropriate.

An average 2,300 square-foot home is estimated to generate between 7,000 and 12,000 lbs of waste during construction. An effective waste management recycling plan may reduce construction material waste by two-thirds, realizing a cost savings for the builder and owner while reducing the burden on local landfills.

In addition, using locally-stocked new building products and incorporating salvaged materials, where applicable, reduces the transportation cost (and green-house gases) associated with job site delivery.

Framing Techniques

By incorporating advanced framing techniques builders can maximize the use of materials, thereby reducing waste and costs. These techniques, in conjunction with engineered materials, improve value, durability, and safety of the home's walls.

Many engineered framing materials provide a superior strength product and use less old growth timber. For example Structural Insulated Panels (SIP) contain a core of rigid foam expanded polystyrene insulation (EPS) sandwiched between two sheets of composite oriented strandboard (OSB). These panels may be used in roofs, walls, and floors to replace conventional sheathing. They have a higher R-value, reduce air leakage, resist moisture, transmit less sound, and are stronger and more earthquake resistant than conventional framing.

In addition, EPS does not out-gas harmful chemicals nor does it sustain a flame. Since these engineered panels are pre-cut, job site waste is reduced and the completed wall contains about 75% less raw wood than a conventional stick-framed wall. They are factory manufactured and can be custom sized for each home, resulting in a structure that is stronger and more energy efficient, while requiring less labor to complete.

Another eco-friendly framing method uses manufactured steel, which is recycled, strong, lightweight, and less labor intensive. Steel is inherently rot- and insect-proof and resistant to moisture damage. It is fastened, not nailed, so it can be disassembled and reused with minimal scrap.

Concrete masonry framing offers strong resistance to natural and man-made disasters. It is fire resistant and offers protection from wind, termites, rot, and mildew. Reduced structural flexing minimizes cracks and nail pops on interior walls and lowers routine maintenance. This stronger envelope also lowers insurance premiums with many carriers.

The preceding information was gathered in part from the following sources

• NAHB Green Building Guidelines
• Olde Heritage Builders
• National Concrete Masonry Association
• Carolinas Concrete Masonry Association
• Portland Cement Association
• Earth Advantage Homes
• Green Home Builders of the Triangle, Green Building Initiative
• Taunton Press
• Appraisal Journal