Several electric utilities in New England developed the Energy
Crafted Home program to encourage the construction of single-family
and multifamily homes that are substantially more energy efficient
than those built to code. New construction energy efficiency
programs tend to be cost-effective for utilities because it's less
expensive to build a home right the first time than to retrofit it
later.
In some respects, the Energy Crafted Home program is similar to the
Canadian R2000 and the Bonneville Power Administration Super
Good Cents programs. It is performance-based and provides builders
with training and technical assistance in getting their homes to
achieve the program specifications. Field inspections of each home
are also part of the program. Builders receive cash incentives for
each qualifying home, but even more important to the builders is the
program's marketing support.
In other respects, the program is unusual. It is open to all homes
regardless of fuel type. (The financial incentives are significantly
larger for electric heat homes.) Besides heating, other end-uses are
targeted, including lighting and cooling. Blower-door tests verify air-
tightness standards, and indoor air quality issues are addressed, in
part by requiring mechanical ventilation.
Because of the program's thermal and ventilation standards, these
homes should be less expensive to operate, healthier to occupy, and
more comfortable to live in-significant advantages to both the
builder and homebuyer.
Table 1: Building Shell Performance Requirements
Heating: <= 1.4 Btu/ft2 of shell/heating degree-day
Cooling: <= 2.7-3.7*Btu/ft2 of shell/cooling degree-day
(*depending on cooling load of utility region)
Infiltration: <= 1.0 in2 of opening/100 ft2 of shell
(at 4 Pascals of pressure difference)
Moisture
control: Continuous vapor barrier
(on walls, ceiling and floors, around
insulated ducts, and under slabs)
Indoor air
quality: Pollutant source reduction and continuous ventilation
(60 cfm in small homes and 100 cfm in larger homes)
Fossil-fuel
appliances: Sealed or closed combustion on heaters and water heaters
(fireplaces/stoves must have airtight doors and
fresh air supply)
Lighting: Hard-wired fluorescent fixtures are encouraged
(also, bare-bulb fixtures must have compact fluorescents)
Program Design
The program helps builders improve their construction standards by
providing training and technical assistance, an energy analysis of
each home, and a series of quality assurance inspections during
construction. Financial incentives defray some or all of the added
costs of building a home. And marketing to homebuyers and
promotion to real estate agents and lenders helps create demand.
The Specs
The Energy Crafted Home program achieves energy savings in new
construction by increasing thermal efficiency. With performance-
based energy standards, builders can maintain design flexibility and
participate regardless of the size or complexity of the home. Every
house must meet building shell energy performance budgets for
heating, cooling, and infiltration (see Table 1).
Workshops
All interested builders attend two-day training workshops. The
utility sponsors these workshops frequently throughout the region,
and at a very low cost. Builders learn to treat a house as a system,
with special attention to moisture, indoor air quality, thermal
integrity, isolation of combustion equipment, and controlled
ventilation (instead of uncontrolled infiltration). For example, they
are shown various techniques for minimizing thermal bypasses and
installing continuous vapor barriers in difficult areas (namely,
around windows and in corners). They are also provided with a
reference manual and computer software so they can perform their
own building thermal performance simulations. The builder's manual
includes program requirements, many examples of good construction
detail, and explanations behind recommendations and requirements.
A number of small builders in New England already use many of the
state-of-the-art construction details recommended at the workshops,
but the majority of the participants see these construction techniques
for the first time at the workshops.
Plans Evaluation and Technical Support
Builders submit plans for each Energy Crafted Home to the utility
that will serve it. An evaluator reviews the blueprints and system
details for compliance, and uses a computer simulation program to
determine whether the design meets thermal efficiency standards.
Modifications are generally required, so the plans evaluator analyzes
the energy performance and thermal integrity of various changes
and works with the builder to select upgrades to meet program
specifications.
Even after the training workshop, most builders need additional
technical assistance with such issues as continuous air/vapor
retarders, state-of-the-art heating and ventilation equipment, and
overall design for maximum thermal performance. Most builders feel
the plans evaluation process is beneficial and depend on the
evaluators' technical and construction expertise as they design and
build their first Energy Crafted Homes.
Inspections and Quality Control
The utility ensures that a home is constructed to specification by
paying an inspector to make three site visits. The first inspection
verifies that the insulation and air/vapor retarder are properly
installed. The primary purpose of the second inspection is to confirm
that the building meets the program's air-tightness standards. The
inspector uses a blower door test to measure infiltration and to
identify any air sealing still required to meet program guidelines.
This inspection takes place after the drywall is in place, but before
any trim has been installed. The third inspection is a final walk-
through once the home is complete. While the heating, domestic hot
water, ventilation, and distribution systems are generally examined
at each stage, the final inspection confirms that these systems and
their controls are functioning properly. Sealed combustion is critical,
as is proper air flow and balancing of ventilation systems. The utility
inspector checks lights, duct and pipe insulation, fireplaces, wood
stoves, and exhaust hoods during a final inspection.
When the house is complete, the utility certifies it as an Energy
Crafted Home and registers the builder as an Energy Crafted Home
builder. An owner's manual, which details the advantages of owning
an Energy Crafted Home and how to care for it, is then presented to
the buyer.
Hard Cash
The utility pays financial incentives for each home. For electrically
heated homes, the incentives ($1,650 for single-family and $900 per
multifamily unit) were designed to cover the average incremental
cost to the builder of going from a code-built home to an Energy
Crafted Home. Incentives for fossil-fuel-heated homes ($150 for
single family and $75 for multifamily) are based on the electrical
savings for lighting, water heating, and cooling. In addition, builders
receive $25 for each hard-wired fluorescent fixture they install. It
turns out the primary incentive for most builders is not the money,
but the program marketing-more about this later.
Getting Everyone Involved
A Commonwealth of Utilities
The Energy Crafted Home program was developed jointly by several
electric utilities in Massachusetts, Rhode Island, and New Hampshire.
(The participating utilities are Blackstone Valley Electric, Boston
Edison, Eastern Edison, Granite State Electric, Massachusetts Electric,
Narragansett Electric, Newport Electric, and Western Massachusetts
Electric.) The program began in early 1989 when the utilities
established the Joint Management Committee to oversee program
development, builder training, marketing, and implementation. It
includes representatives from each of the participating utilities, and
involves builders, technical experts, and a consultant who helps
coordinate it. The Joint Management Committee met biweekly for the
first two years and continues to meet monthly.
Coordinating the effort of so many separate utilities presented many
challenges; fortunately, the resulting regional program has many
advantages. Most builders work across utility jurisdictions, so having
one program means they need to learn only one set of program
requirements and attend just one training session. It is also more
cost-effective to have one program and marketing plan to reach
customers throughout the region.
True Trade Allies
Using a regional design approach, the utilities were able to pool
resources and retain the services of experienced energy-conscious
builders, architects, and engineers. They assembled more than a
dozen teams to work on specific issues such as the building shell,
cooling, lighting, appliances, construction details, ventilation, and
passive solar design.
The utilities' Builders' Advisory Board was established to provide a
forum for communication between the Joint Management Committee
and builders. Through regular meetings of the Builders' Advisory
Board, builders have been kept apprised of program status, and
invited to provide input and feedback on documents and training
sessions. Several marketing tools, including a video for prospective
clients and a display booth for home shows, were developed based
on suggestions from the Builders' Advisory Board.
The involvement of so many industry "gate-keepers" has been
critical to the program's acceptance by the building community.
These local professionals all feel some program ownership and hence
are likely to build Energy Crafted Homes themselves and encourage
their colleagues to do likewise. A measure of the programÕs success is
its endorsement by such diverse groups as the Massachusetts
Association of Home Builders and the Northeast Sustainable Energy
Assoc. (formerly Northeast Solar Energy Assoc.). NESEA has also
endorsed and helped to market the program, and its members have
played key roles as program designers, workshop instructors, and
inspectors.
Performance Standard Approach
The utilities and building professionals selected performance-based
standards for several reasons. Design flexibility is critical for most
participants. Another advantage is that, as building technologies or
building codes improve, it is simple to update the program by
changing performance targets. Performance standards also "require"
overall energy savings, so contractors aren't tempted to trade off
sloppiness or inefficiency in some areas to meet prescription
standards in others. Actual savings should therefore be higher for
performance-based programs than prescriptive programs.
Marketing
The program can only succeed if builders erect and people buy
Energy Crafted Homes. Without widespread acceptance, a technically
sound program will not save much energy. Thus, marketing targets
both builders and buyers with the message that energy efficiency is
an indispensable feature in a new home.
The core of the marketing strategy is to communicate that energy
efficiency is not only an economic feature of a new home but part of
a package of features as important as siting or kitchen design. These
features include comfort, durability, and environmental safety.
Reduced energy costs are assured through energy analysis and
inspections during construction. Educational materials emphasize that
features such as mechanical ventilation and sealed combustion
appliances, which are not standard in new homes, can significantly
reduce risk of unsafe air quality in homes. Energy-efficient homes
have fewer drafts and temperature swings than do traditional
homes. Moisture damage is prevented by extensive use of vapor
retarders and proper exhaust systems.
Reaching Builders
To get the program going, we sold it first to builders. The message to
them combined two themes:
- the marketing competitive advantage-"looking for a hard edge in
a soft market"-something to set the builder apart.
- the fear of being left behind in a changing market-"the market
for inefficient homes is disappearing."
In both cases, the idea is that the Energy Crafted Home package of
features will help give them a sales advantage over others that lack
these features. Both small custom builders and large developers
receive assistance with marketing.
Educating Homebuyers
Utilities and builders are using creative strategies to enhance the
marketing of certified homes. Feature articles in newspapers, lawn
signs, homeowner manuals, cooperative advertising in real estate
journals, home show booths staffed by Energy Crafted Home builders,
videos, television advertising, brochures, educational booklets, and
promotional items such as hats and pens are just a few of the
marketing approaches currently in place. The single program logo
and name reinforced the message.
The newest marketing piece is a video, created as a result of
builders' requests. The video, made for builders to distribute to
prospective clients, features Energy Crafted Homes in various layouts
and architectural styles. Builders explain the quality of construction
and satisfied customers talk about lower fuel bills, increased comfort,
and environmental responsibility. An abbreviated version is
currently running as an ad on cable television.
Evaluation and Future Direction
The utilities are evaluating the program by way of interviews and
focus groups with program designers, utility staff, plan evaluators,
field inspectors, trainers, participating builders, non-participating
builders, and recent and prospective homebuyers. The biggest
barriers to builders are the slow market and the relatively low
priority most buyers place on energy efficiency. Preliminary results
indicate that most builders are aware of the program. Potential
homebuyers, however, remain largely unaware of the program,
indicating a need for marketing to target them.
A small, two-year end-use metering project began in January 1992.
Sample program and control homes with similar floor plans and
occupancy patterns were built by the same developer. The study is
monitoring many end-uses. In addition, the whole building load and
indoor and outdoor temperatures will be measured. Computer
analyses for these homes predict a reduction of 30-40% in space
heating for electric heat homes as compared to code, and a 40-50%
reduction for fossil heat homes. (The difference in savings is due to
the stricter code for electric heat.) The measured data will be used to
modify the results of the computer simulations. While the measured
results are not yet available, a preliminary analysis was presented at
the American Council for an Energy-Efficient Economy Summer Study
in August.
Converting the Building Industry
Builders routinely depend on subcontractors for insulation, vapor
retarders, heating systems, plumbing, and electrical work. One of
their biggest challenges has been finding installers willing to comply
with program standards. One way to expand builders' choices of
qualified subcontractors would be to offer focused training sessions
and "Energy Crafted Home Installer Certification." A ventilation
workshop and certification program already exists.
NESEA's annual Quality Building Conference and workshops are
another avenue for providing more education to program builders.
Other options include an information hotline or a panel of experts
who could be available to answer questions and provide advice.
Currently, evaluators and inspectors still provide most of the
technical support.
In the first full year of implementation, the program trained over
400 builders who built nearly 150 Energy Crafted Homes. Most of the
1992 workshops are already booked to capacity. The regional goal
for 1992 is to begin construction of another 400 to 600 single- and
multifamily units (an ambitious goal in New England's slow market).
Ultimately, the utilities plan to include 30% of the new, electric heat
homes in the program.
References
- A more detailed version of this paper is being published in the
Proceedings of American Council for an Energy-Efficient Economy
Summer Study, 1992.
- Fryer, L.R., S.L Cowell, and B.J. Wall. 1990. "Energy Crafted
Homes: A New Residential Construction Program." Proceedings
from the Energy Efficient Building Association 1991 Excellence in
Housing Conference, pp. B29-39.
- Energy Crafted Home Builder's Manual, 1990.
- REM/DESIGN Version 1.03 Residential Energy Evaluation
Program User's Manual, Architectural Energy Corp., Boulder,
Colo.
- Sugden, J.W., 1992. "The Energy Crafted Home Program: Gaining
Acceptance in the Marketplace." Proceedings from the New
Construction Programs for Demand-Side Management Conference,
pp. 14-23.
Typical Construction Detail
The performance-based approach of the Energy Crafted Home
program results in a great deal of flexibility on the part of the
builder. However, several basic construction details are typical of
many Energy Crafted Homes.
Walls: Some house plans pass the thermal analysis with R-20
or -21 in the walls (226 studs with cellulose or high-density fiber
glass) but most are 226 construction with an inch of rigid foam on
either the inside or outside (R-24 to R-28 total). The foam, typically
extruded polystyrene or foil-faced isocyanurate, helps reduce
thermal bypasses through the studs, and in some cases can function
as the air/vapor retarder.
Ceilings: Virtually every Energy Crafted Home has more than
the R-30 ceiling insulation required by code. R-40 is typical, and
builders use various techniques to minimize thermal bypasses.
Windows: Since windows can be a major source of heat loss
and solar gain, most Energy Crafted Homes have either thermal low-E
glazing or argon-filled glazing. The thermal analysis considers
orientation, unit U-values, solar transmittance, and exterior shading
in evaluating the effect of windows on heating and cooling loads.
Heating Equipment: Heating systems and fuels vary, but they
are consistently smaller and more efficient than the traditional
installation. Design loads are typically 25-50,000 Btu per hour
instead of 50-150,000 Btu/hr. Many houses have integrated systems,
where one heating unit provides both space heat and domestic hot
water.
Moisture Control: Energy Crafted Homes must also comply
with moisture control specifications. Vapor retarders reduce the
potential for condensation of water vapor in walls and attics, which
can lead to dry rot and structural damage. Although technically
required by building codes, vapor retarders have often been no more
than kraft paper, often improperly installed. In Energy Crafted
Homes, a continuous vapor retarder must be installed on exterior
walls, ceilings, and floors and around insulated air ducts. Moisture
retarders are also installed under slab floors and on crawl space
floors. These continuous vapor retarders also serve as air barriers,
significantly reducing infiltration.
Air Quality Control: With the very low natural infiltration rate
of an Energy Crafted Home, special precautions assure good indoor
air quality. The best solution to indoor air pollutants is to eliminate
the source, so builders avoid materials with high urea-formaldehyde
content. Since radon is another potential concern, program homes are
built with a sub-slab layer of stone which will permit the installation
of a sub-slab ventilation system, should radon mitigation become
necessary.
Ventilation Equipment: Most Energy Crafted Homes have heat
recovery ventilators, sometimes fed directly into the heating system
ductwork. The rest have exhaust-only ventilation, which typically
exhausts air continuously from bathrooms and kitchens directly
outside, drawing in fresh air through inlets in living room and
bedroom walls. Either method of controlled ventilation is acceptable;
however, less energy is required to heat air that has passed through
a heat recovery ventilator.
In addition, mechanical ventilation brings in fresh air and exhausts
air which may contain pollutants and/ or excess moisture. Systems
must provide 60 cfm of continuous ventilation in small homes and
100 cfm in larger homes. These levels of ventilation are based on
ASHRAE recommendations of 15 cfm per person above .35 ACH. An
Energy Crafted Home-certified installer must install and balance the
system.
Heating and Domestic Hot Water: All fossil-fuel heating
appliances must have sealed or closed combustion, where outdoor air
is provided directly to the combustion chamber and flue exhaust
gases are vented directly outside. No interior house air is used for
combustion, so there is no risk of backdrafting.
Lighting Hard-wired fluorescent fixture are encouraged, and
for each one installed, the builder receives an additonal incentive.
Compact flourescent bulbs must be used in all bare bulb, non-
decorative sockets inside an Energy Crafted Home.
Measuring 40% Savings
Is it possible to measure the energy savings obtained through
construction of new, efficient homes? The Pacific Northwest found
that it was possible to determine the energy savings with surprising
confidence. Moreover, the results were obtained with old-fashioned
technology.
In 1985, Bonneville Power Administration (BPA) wanted to test the
efficacy of the proposed insulation standards for new electrically
heated houses in the Pacific Northwest. The standards required
heavy insulation, triple-glazed windows, and mechanical ventilation.
Like those in the Energy Crafted Homes program, participating
builders received extensive training prior to construction (in addition
to generous subsidies). The monitoring was surprisingly primitive:
separate kilowatt-hour meters for the furnace and water heater.
That, along with the normal meter on total use, provided submetered
data for space heating, water heating, and other uses (including
appliances, cooking, lighting, and miscellaneous uses). One other
device recorded the average inside temperature. The occupants took
readings from each meter every week and mailed them on postcards
to BPA. More than 200 efficient homes, plus an equal number of
control homes, were monitored for two years. (The energy and
temperature data for a typical house are shown in Figure 1.) The houses were
inspected for physical factors, such as infiltration rates and general
quality control. Finally, builders and occupants were surveyed to
order to determine costs, appliances, demographics, and
satisfaction.
These data were sufficient to determine that the homes built to the
new standards used about 40% less space heating energy than those
built to current practice. The actual metered difference was smaller -
about 30% - but the efficient homes were also 25% larger than the
control homes and were kept warmer. If the two groups of homes
had been the same size and operated at the same temperature, then
the savings would have been over 40%. The energy use of each
house depends on the climate, insulation levels, appliances present,
and occupants' behavior, but the average savings were unmistakable.
(The range in performance and savings are shown in Figure 2.) The results of the
study convinced the Northwest to adopt new, tighter building
standards. (For more on the savings from the standards, see
Model Conservation Standards
Prove Themselves During Cold Snaps," HE, Sept/Oct '90, p. 11-
12.)
-Alan Meier
Good Cents' Measured Savings
Fall Short of Prescription
Just a bit to the north, Central Maine Power has been running a
training and incentive program to encourage construction of new,
efficient, electrically heated homes for several years. Central Maine
Power's Good Cents program did not prescribe specific levels of
insulation; instead, it required a level of performance under design
conditions (an 80 degrees F temperature difference). This allowed
builders to trade off various features, such as extra glass area with
thicker wall insulation. Builders prefer this kind of standard because
it gives them much more flexibility to meet the demands of
individual clients.
Based on a 1985 field study, the thermal performance of current-
practice new homes was thought to be around 30 Btu/hr/ft2, so CMP
required Good Cents homes to consume less than 16 Btu/hr/ft2 for
those smaller than 1,250 ft2 (less than 15 Btu/hr/ft2 for 1,250 ft2
and larger). Good Cents promotional literature promises a 40% space
heating savings compared to baseline homes. Over 4,500 houses and
condominiums have been built to Central Maine Power's
specifications.
The energy savings were recently estimated in a report by the
consulting firm, RCG/Hagler, Bailly. It evaluated the savings based on
utility bills, engineering estimates, and a small number of
submetered homes.
The engineering surveys revealed one problem: the current practice
houses (that is, the non-participants) were much better insulated
than the utility had supposed: audits found that the average new
electrically heated house's thermal performance was actually 18
Btu/hr/ft2. So, even though the Good Cents houses were also a little
better than assumed, the expected savings were considerably
reduced. The billing data confirmed the engineering estimates: actual
energy savings were only a little more than 20% (about 3,000 kWh
per single-family house).
The analysis was complicated because the Good Cents homes were
larger than the comparison homes, the occupants wealthier, and
many used wood heat. Furthermore, only whole-house billing data
were available for most homes, so space heating consumption could
only be inferred through Princeton Scorekeeping Method (PRISM)
analysis. Logistical problems prevented full use of the submetering
phase of the project. Nevertheless, the small sample of submetered
homes proved to be very reliable indicators of the savings.
RCG/Hagler, Bailly recommended that future studies should submeter
the heating system because data from that portion of the study were
particularly reliable. The Bonnevile results (discussed in the box Measuring 40% Savings") reinforce that advice.
-Alan Meier
Figure 1
Figure 2
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