• Rey Homes

Rey Homes is a production builder in Orlando, Florida interested in building energy efficient homes and green communities.  Site visits to existing homes and BAIHP model home design analysis began in October 2001.  Rey Homes pledges that all of the 200 community homes will meet Energy Star standards (HERS = 86) and the Florida Green Home Designation Standard.

FSEC researchers assisted Rey Homes by recommending strategic paths to compliance and by installing monitoring equipment at two side-by-side homes  under construction in their Villa Sol community.  One home design features an unvented attic and the other a vented attic.  Both homes will be instrumented to allow a comparison of the ventilation and its effect on humidity and energy efficiency.   FSEC staff made regular visits to the two homes in Villa Sol at various construction stages to monitor progress, including attending a mid-point duct integrity inspection conducted by the builder's energy rater.  Data acquisition wires were pulled in both homes to prepare for data collection and some instrumentation was installed, including equipment to monitor the moisture content of roof trusses and thermocouples, and heat flux across the drywall ceilings. With permanent power recently coming on-line in the Villa Sol subdivision, it is expected that all sensors and datalogging equipment will be installed by early summer.

With FSEC assistance, Icynene insulation personnel and consultants conducted an analysis to quantify the air conditioning tonnage reduction from constructing the homes with sealed attics and an Icynene insulation system.  The energy savings from the system size reduction will be used to add other energy efficient and green improvements.

• Sandspur Housing

In 2002, FSEC staff met with representatives from Sandspur Housing, the largest affordable home builder in the nation.  Sandspur constructs approximately 4,000 apartment units per year, most of the units in Florida and Georgia. The company's primary interest in Building America is in receiving assistance for designing low energy-use units with good indoor air quality.  Contact with Sandspur was initiated by  BAIHP subcontractor Florida HERO (Please see section 1.4 Florida HERO) at Brookside Apartments in Gainesville, Florida.

Naples, Florida:  For Sandspur's Naples community, Camden Cove, BAIHP researchers conducted an analysis on all individual units and several apartment buildings slated for construction in 2003 and 2004.  Analysis specifications were based on detailed building plans, communication with Sandspur and their mechanical engineers and HVAC contractor, and Florida HERO's field investigation of the Harbor Cove Community currently under construction in Gainesville.  Some building aspects were assumed to adhere to industry standard specifications until actual specifications could be determined.  Results indicated an opportunity to reduce energy use (and hence energy cost) in a 16-unit apartment building by 20% or more, along with improving indoor air quality, and structural durability.   Although the potential existed to reduce energy use upwards of 70%, such solutions did not balance themselves with first cost and construction time.

An interesting aspect of the analysis investigated cost and energy performance trade-offs using  various types of heating equipment.  The influence of forced air duct leakage was included in the study and proved to have a much larger impact on energy use, indoor air quality, and building durability in certain Florida climate zones than equipment type or efficiency.  As a result of the high degree of quality used to construct air duct systems within Sandspur apartments, these apartments consume less energy for heating and cooling than a similar apartment which uses higher efficiency equipment, with duct systems constructed to industry standard specifications only.  

Recommended energy saving strategies focused on achieving a cooling load a reduction by:

• replacing 100% incandescent with 75% fluorescent lighting
• reducing duct leakage to 3%
• minimizing window area to 6% of floor area
• incorporating window shading strategies that reduce solar heat gain coefficient to 0.2
• locating ducts in conditioned spaces
• increasing cooling system SEER to 13.0
• using white metal instead of dark shingle roofs or installing radiant barriers on the underside of the roof deck
• installing programmable thermostats
• including ceiling fans in all bedrooms and main living areas
• properly sealing all penetrations, air duct systems, windows, doors, etc.
• Air quality improvement strategies focused on including:
• efficient HVAC filtration using pleated return air filters rated with an 11 minimum efficiency reporting value
• filtered mechanical ventilation from the air handler unit to the outside, pulling in fresh air during air handler operation
• mechanical ventilation system commissioning to supply no more than 7.5 CFM of air per bedroom, plus 0.01 CFM per square foot of floor area
• supplemental dehumidification
• quiet, energy efficient bathroom exhaust fans with timer switches which use less than 0.3 watts per cubic foot of air moved
• quiet, energy efficient vented kitchen range hoods in each unit

A summary of all analysis results and building design features was prepared and submitted to Sandspur Housing.  Two meetings were held to review the recommendations.

Moisture Investigations:  FSEC staff tested four Sandspur-built apartment units and installed datalogging equipment in six units at the Landings Community in Orlando where some units had reported moisture problems.  Measured envelope leakage was typical for new construction, and all but one unit had very tight duct systems. HOBO dataloggers were deployed in the air handler of each unit to record interior moisture levels.  Three weeks of HOBO data were plotted for six apartments as temperature, relative humidity, and dew point.  Ambient weather from the nearby Hoak datalogger was included and compared favorably with published Orlando airport weather.

To continue investigating the cause of excess moisture in the apartment units, datalogging equipment was installed in six additional units.  To remedy problems, prototype schemes were evaluated such as utilizing a humidistat in conjunction with thermostat, and installation of a dedicated dehumidifier. Data analysis will be completed by 2004.

Technology Tour: Sandspur Housing staff were taken on a tour of the David Hoak demonstration home to show specific equipment and the role it plays in an overall systems engineering approach. After the tour, discussions continued on the Landing Community analysis.  This allowed personnel to view firsthand some of the Building America principles and practices so that they could explain these concepts to others in the Sandspur organization.

• Southern Energy Homes

In 2002, FSEC received a request to certify the Southern Energy Homes (SEH) factory in Addison, Alabama for Energy Star compliance.  A plant visit in August 2001 examined opportunities to enhance manufacturing productivity.  Three model homes were tested for Energy Star certification, recommendations made, and Energy Star plant certification paperwork submitted to US EPA.

In 2003, discussions continued with SEH plant personnel for conducting an analysis at one of their factories using the UCFIE simulation tool.  On January 27 and 28, FSEC conducted site visits and performed diagnostic tests on several problem homes, and submitted recommendations via a trip report in February.  Armed with these recommendations, FSEC conducted factory personnel duct test training in four Southern Energy Homes factories.

• Stylecrest Sales (Coleman HVAC Systems)

FSEC researchers met with Stylecrest Sales and discussed Energy Star plant and home certification procedures.  Cost data was gathered for a variety of HVAC system sizes used in their different home models.