GREEN PRACTICES IN HOME CONSTRUCTION 3

In This Chapter 3-1  Innovative methods and materials  Achieving energy efficiency  Factors for calculating cost/benefit

Innovative Construction Methods and Materials 3-2  Modular building and panelized construction materials  Structural Insulated Panels (SIPs)  Precast Concrete Panels  Insulating Concrete Forms (ICFs)  Straw-Board Panels

Structural Insulated Panels (SIPs) 3-3 Source: Reprinted with permission of Structural Insulated Panel Association,

Precast Concrete Panels 3-4 Source: Reprinted with permission of NAHB Research Center’s Tool Base Services,

Straw-bale Homes 3-5 Source: Reprinted with permission of Tipping Mar & Associates,

Optimum Value Engineering (OVE) 3-6  Advanced framing technique that reduces lumber used for framing and creates more room for insulation in exterior walls  See Figure 3.4

Energy Efficiency 3-7  Energy efficiency: Primary goal of green consumers  Energy model predicts how design for home or building performs against benchmark  Energy models may be conducted on-site or virtually

HERS Index 3-8  Energy index begins in preconstruction phase  Certified rater evaluates design and construction plans using specialized software  Rater works with builder to optimize energy efficiency  Once home is complete, rater will conduct inspections and tests, including a blower door test and duct test, and give the home a HERS Index

HERS Index 3-9  Benefits:  Obtaining a widely accepted rating  Using rater who is qualified and certified  Quantifying energy efficiency goals and verifying that they are met  Qualifying for energy mortgage  Qualifying for federal energy efficiency tax credits  Meeting ENERGY STAR standards

HERS Index 3-10

Determining Energy Performance in Built Homes 3-11  Energy assessment: Identifies and predicts issues with energy performance using methods and tools  Energy survey: Easy do-it- yourself tool that identifies energy efficiency issues and goals, as well as need for comprehensive energy diagnostics

Hot Water Heaters 3-12  Technologies include:  Drain water heat recovery systems  On-demand water-circulation pumps  Tankless water heaters

Retrofitting, Remodeling, and Renovating Existing Homes 3-13  Retrofitting –Lower-level upgrades to improve energy efficiency and IAQ, conserve resources, and meet other green goals  Remodeling –Higher-level options that change appearance of home and have greater impact on energy efficiency, IAQ, and resource conservation  Renovating –Installation of advanced systems that substantially change performance of home

Challenges 3-14  Changing elements of building envelope: Impossible or cost- prohibitive  Changing orientation of entire home: Often impossible  Installation of advanced systems: Cost-prohibitive

Challenges 3-15  Clients often conflicted about whether keeping aspects or features in place is “more green” than gutting and replacing  Work must be scheduled according to health, comfort, and availability of clients and customers  Be wary of greenwashing when looking for quick retrofits  Remodeling and renovating must be sequenced according to client preferences

Challenges 3-16  IAQ issues often arise  Integration of systems requires skill and innovation  Clients balancing priorities with budgetary considerations: Difficult  Zoning laws and building codes may limit options

Cost/Benefit Analysis 3-17  Cost/benefit analysis of new construction is difficult  Depends on extent of project and value expectations of clients and customers  See charts in Figures for payback times, cost savings, and ROI numbers for each option

Exercise 3-18  Focuses on factors for calculating cost/benefit and identifying client and customer value perceptions  Read the scenario and answer the questions that follow.