Research Project Summary Information
Reference Design Guide for Highly Energy Efficient Residential Construction:Refrence Design Guide for Highly Energy Efficient Residential Construction(ST9672-1)
Vermont Energy Investment Corporation
The Energy Star Program for New York State rates new construction homes on an energy use basis, and provides the home with a Home Energy Rating System (HERS) score. The average HERS score for new construction homes within New York is 87, from data reviewed over the past five years. NYSERDA's R&D Buildings Group is developing an Advanced Building Program that seeks to promote and bring attention to a much higher HERS score; 92 or greater. Currently, less than 2% of the over 5,000 samples of NY homes have scores greater than 92. As a first step, we will assemble reference designs that present and exemplify advanced building techniques, which are reflected in higher HERS scores. There is a significant departure point in a graphical plot of HERS scores for the State, which occurs after HERS 90. NYSERDA feels that a building with a HERS 92 or greater indicates a much higher performing building in terms of energy use and quality, and would like to make the systems and components within these types of buildings available to more of the audience.
Vermont Energy Investment Corporation, (VEIC), is extremely familiar and involved with residential new construction practices, programs and studies being performed. VEIC is teaming with New York State Builders Association Research and Education Foundation (NYSBAREF), Conservation Services Group (CSG), and New York Builder Kevin Stack, to encompass New York States building arena, and determine why some homes being built perform markedly better than others in terms of energy use. The goal of efforts will be to determine what makes a residential building obtain a higher than average HERS rating.
This project will involve field interviews with builders, manufacturers, and equipment suppliers.
Step 1 - Determine the current performance level of buildings in the home construction market, including subsystems and their costs, which comprise this subset.
Step 2 - Acquire data reflecting current practice for at least eight completed residential buildings.
Step 3 - Acquire data points reflecting possible and achievable outcomes for planned buildings.
Step 4 - Contractors will provide their own design concepts in graphical and schematic level plans that will meet high performance standards.
Step 5 - Assemble all acquired data from Steps 1 - 4, and create a final report for presentation.
Results of the field research will provide knowledge that may drive internal program development. The results will also assist reference for external people, including builders and home buyers. NYSERDA programs should be able to place dollar values on energy reduction efforts in a newly constructed home.
The Guide identifies strategies, components and costs associated with achieving high performance building. If followed, the NY Energy Code will yield energy efficiency adequate to meet Energy Star program requirements, which is not the case due to < 12% penetration in NY State. The study outlined strategies, still, the challenge is getting builders to understand and properly implement them, in addition to getting consumers to understand and value the strategies. Typical HERS ratings > 90 involve better wall systems, more efficient mechanical distribution systems and use of high efficiency water heating equipment. Under the Energy Star Program; many homes built in NY State do not meet code, 2x4 construction is still prevalent, no penalty for house size (avg. Energy Star homes evaluated was 3,700 sq ft.), code minimums for mechanical efficiencies are outdated, window U-value requirements could be more stringent, ducts are not sealed and waste substantial energy, use of central air conditioning is increasing, and fluorescent lighting is not the norm. For additional costs, < $5,000, a home can be vastly improved, with no cost increase associated, as well as improve the quality of labor and design thought. A sample set of >1,900 Energy Star-rated home ratings were evaluated, and it was determined that the predicted energy use via REM/Rate averaged 10% greater than actual usage. Analysis also reveals an increased HERS score from 86 to 90 does not correlate to less energy use
Vermont Energy Investment Corporation
128 Lakeside Ave., Ste 401
Burlington, VT 05401
Building Construction Methods
NYSERDA Contact Information
R&D - Buildings Research