HGA Home is built to be a sustainable model

HGA Home is built to be a sustainable model

SOUTHAMPTON, N.Y. — Following the fire that destroyed the home of David and Saundra Dubin in late 2008, the Hamptons Green Alliance (HGA), an association of building professionals in the Hamptons that promotes green building and maintenance practices, and a team of architects, tradesmen and suppliers, renovated the original home into a 4,800-sq.ft. house that just recently received U.S. Green Builing Council LEED Platinum certification.

The house is also embodied carbon neutral and net-zero energy thanks to a gamut of technologies such as a geothermal system, solar thermal system, solar photovoltaics, solar film, low-flow plumbing fixtures and dual flush toilets, Smart house technology and a home energy monitoring system.

The team of building professionals developed a plan for constructing the Dubins’ new home — the HGA House. The team working together integrated multiple means and methods of design and construction to achieve maximum efficiencies, which they coined “Systems Integrated Home.” By implementing the team’s Systems Integrated Home approach, the HGA House achieved 104 points from USGBC’s LEED for Homes rating system.

“The benefit of a Systems Integrated Home is that by doing so we are able to understand the relationships between the many subsystems that make up a residential building project,” explained Tim Dalene, senior project manager of Telemark, the project’s general contractor. “With proper planning from the beginning we are able to minimize the size of the systems used, reduce cost, drastically reduce changes and eliminate architectural redrawing.”

Geothermal system

According to Dalene, a geothermal system was picked mainly because of its efficiency.

The geothermal system is an open loop system with Florida Heat Pump model ESO61 in the basement, Florida Heat Pump model ESO49 in the attic, and a steam humidifier in the basement system.

“An open loop system was chosen primarily as a cost issue and secondarily due to the depth that we could drill,” said Dalene. “Long Island has an aquifer and it is more efficient and environmentally preferable to utilize a supply and dispersion system as opposed to a closed loop.

“One of the goals of the project was to be independent of fossil fuels,” continued Dalene. “Since geothermal runs off electricity, we can then utilize solar paneling to counter our increased electrical usage caused by the geothermal HVAC system.”

Flanders Heating and Air Conditioning, Riverhead, N.Y., installed the geothermal system and humidification, air filtration and air exchange equipment, which took five months.

According to Doug Matz, president of Flanders Heating and Air Conditioning, working on a Systems Integrated Home was a great process since there was a common goal to build a net-zero energy house at a fixed price and to work as a team.

“We could look at the budget of different contractors involved, so we could look at the impact of the different decisions that were made,” explained Matz. “For example, depending on what type of insulation was used, if the insulation contractor used foam instead of standard fiberglass, this impacted the mechanical side of the project, so we were able to redo our loads and decrease system sizes, bringing costs down.

Solar systems

“As the mechanical system changed, so did the amount of alternative energy needed to offset the energy footprint, thus, the PV solar contractor needed to make equipment decisions, depending on how much was needed to produce the proper amount of energy,” said Matz.

For the solar systems, a solar thin film and regular PV panels are being utilized. The thin film, by Unisolar, produces 6.34 kW, and the conventional PV panels, by Sun Power, produce 3.6 kW. The solar thin film is located on the south facing part of the house while the solar panels are on the east and west facing roof.

“The thin film was selected because the house had a standing seam metal roof and the thin film panels fit perfectly between the panels,” said Dalene. “The architect felt the appearance of thin film was an improvement over a traditional PV panel.”

The home also has a solar thermal system, provided by Sun Max, for domestic hot water. The system is comprised of three sections of evacuated tubes, each section containing 30 tubes each, and the performance expectations are 105,000 BTUs daily.

“The arrays are connected in a series through a manifold that leads to two heat transfer units,” explained Dalene. “The first transfer unit is connected to a 100-gal. domestic hot water tank while the second is connected to a 250-gal. storage tank, which is used for various energy needs depending upon the season and demand.

The solar thermal system has the ability to act as a primary heat source in the winter, which takes advantage of the BTUs being produced while decreasing the demand on the geothermal HVAC system. The excess hot water goes through heating coils to distribute heat through the ductwork to heat the house as a primary heat source. During the summer, the system acts as the heat source, providing domestic hot water and heat dump for pool heat mixing with the return water from the pool.

There is also a monitoring system, allowing the homeowner to control all of the zones of the HVAC system and the lighting, as well as the security system.

“What is quite amazing is that it can be accessed via the Internet, which allows the owner to remotely control the system,” said Dalene. “This is certainly quite a benefit on a hot summer day for those that would like to turn the A/C on remotely just as one leaves for home. These type of systems not only conserve energy, but make a home a more comfortable place to live.”

The home also conserves water with Kohler low-flow plumbing fixtures and toilets, and a rainwater harvesting system in which water is captured from the roof of the home and stored in the ground to be used at a later time to water the grounds.

A model to follow

The home’s power usage will be tracked for a full year, and then compared to power usage of the original home. It is imperative to measure the effectiveness of the sustainable technologies since this project was done as a model for others to follow.

“Since this is a renovation we will be able to measure energy usage before and after,” said Dalene. “The HGA members offered to take on the project at cost and the owner agreed to share his historical energy data. We wanted to try to prove that we could build a large luxurious home that was energy efficient and esthetically pleasing. If successful we would then be able to present a financial argument for why sustainable building made sense for both large and small homes.

“We believe that unless sustainable building is cost justified, ‘green’ building will not be universally accepted,” added Dalene. “The HGA house is an important example of how the use of sustainable technologies and methods are cost effective and desirable.”