Helping builders and architects comply with Energy Star requirements
Although energy efficiency measures are generally popular with the homebuyer in this era of sharply rising fuel prices, choosing the measures to be installed in a new home falls primarily to the builder or architect. The range of measures that affect a building’s energy performance are found in every system and assembly in the building. Much of the time these are unknown to the homebuyer. Decisions such as how to weight each measure, which are cost effective, which have impacts on other systems, can be migraine-inducing but can affect occupant health and safety and building durability. Wouldn’t it be great if there were a professional knowledgeable about these systems and their interactions? Happy day – there is.
These professionals are called Home Energy Raters. They are nationwide in coverage, they have a thorough and disciplined training and continuing education program, and they are accredited through a national governing body (RESNET) whose authority comes from the U.S. Department of Energy (DOE). HERS Raters, as they are called, perform energy simulation analysis using software that must pass muster against DOE tests. The Raters follow established protocols for gathering information and modeling buildings and perform on-site verification of air leakage and duct leakage rates using blower door testing equipment. Some Raters also perform infrared imaging.
HERS Raters are also the primary mechanism for qualifying homes for the U.S. Environmental Protection Agency’s Energy Star for Homes Program. Raters are closely aligned with building scientists as well, and they are the network that takes much of what is learned in the building science community and helps to put the knowledge to work in the field.
In the central Ohio area, Cornerstone Energy Conservation Services is an accredited Home Energy Rating System (HERS) Provider. Cornerstone was formerly the energy services division of Foundations 4 Energy. The Energy Star Homes Program at Foundations 4 Energy had grown considerably in recent years. “Foundations 4 Energy was a pioneer in establishing a knowledgeable, reliable and reasonably priced certification service for this important program,” the director of Cornerstone Energy says.
A Home Energy Rating is a scoring system that helps a consumer to compare homes of different make-up based on their energy loads. It is similar to a Chapter 4 compliance procedure for the International Energy Conservation Code (Building Design by Systems Analysis) in that it compares a geometric twin of the building, one with energy systems assigned minimum R-values, U-values and equipment efficiencies (the Reference Building), to the one that is as the builder or architect designed it. For code compliance, the as-designed building must use equal to or less than the energy of the reference building to pass. In the HERS rating, the difference in the as-designed and reference homes is assessed, and the difference is given a score.
The testing and inspections are extensive. The HERS Rater will examine the attic insulation for depth and consistency, and he/she will many times inspect prior to drywall for insulation defects and make sure areas behind tubs or showers, stair stringers, etc. are insulated. If the company has infrared scanning equipment, they may wait to do one inspection.
Blower door and duct leakage testing are required. The blower door not only shows how and where air leaks occur, but also can determine what level of air tightness is best to keep the indoor environment healthy. Duct leakage is the most common energy defect. This becomes less of a problem if the ducts are run inside the building envelope, but a great many homes run at least some ducts through attics and ventilated crawl spaces.
Energy Star and Other Programs
Calculating the most cost-effective package of energy-saving features in a new home can be difficult and time consuming for building design professionals. The typical homebuyer, though he/she wants an energy-efficient home, will not expend the effort to get the best package. By looking for the EPA’s Energy Star label, the homebuyer will be assured of a level of performance above the minimum efficiency rating.
Comfort, quality and an affordable operating cost are combined and known as building performance. Building performance may be affected by a simple change. A client may want a small sitting room bump-out that adds 100 square feet or so of glass. While other buildings perform well with a standard U-value window, that one room may become a monster heat generator in the summer and a cold sink in the winter. The temperature difference from another room to that room may cause the homeowner to tinker incessantly with the thermostat until they finally call the builder.
Consulting with the Rater initially at the blueprint stage will allow the builder/architect to assess what-ifs to find corrections for common problems. If the designer has command of pricing, the consulting exercise can result in improvements that add little or no up-front cost to the building.
The staff of Cornerstone Energy Conservation Services has been in the energy rating and energy efficiency business in some facet since the 1970s. As a HERS Provider for the last two years, Foundations 4 Energy began by fielding Raters through the Home Energy Ratings of Ohio Program in 2001.
Cornerstone Director Terry Smith was formerly a Residential Technical Specialist with the Ohio Department of Development/Office of Energy Efficiency, where he was involved in a wide range of programs and initiatives. They included writing procedures and protocols for energy efficiency programs, building energy code development and training, advanced building science demonstration projects, and utility demand side management program oversight.
Cornerstone Energy Conservation Services would like builders and architects to know that the analytical work and then the follow-up testing to assure that buildings are performing efficiently and properly is Cornerstone’s expertise, and that we are ready to help you comply with the Energy Star requirements. Together, we can conserve energy and preserve the environment.
|Cornerstone Energy Conservation Services
1320 McKinley Avenue
Columbus, OH 43222
Builders - The Energy Policy Act of 2005 gives builders who construct new energy-efficient homes certain breaks, including a credit for energy-efficient heating and cooling appliances and other items. The credit is $2000 for homes that exceed the IECC 2004 energy code by 50%.
Architects – The new bill has, in its commercial buildings section, a $1.80 per square foot credit for buildings that exceed the ASHRAE 90.1-1999 energy code by 50%. The credit is for the building owner. Considering that school districts are tax exempt and the bill allows the owner to assign the credit to the designer, architects who design buildings that meet the requirement could make up to $1.80 per square foot.
Cornerstone Energy Conservation Services is among the companies able to certify that the code requirements are met to achieve these tax credits.