Remodeling Tips
for the Green Home
by Gardner/Fox
for the Green Home
by Gardner/Fox
Mechanical Systems
A green home should have a balanced heating, ventilation, and air-conditioning (HVAC) system. These systems push out stale indoor air and condition (preheats or precools) the outside air coming in for maximum efficiency and optimal air quality.
Modern heating and cooling equipment offers increased efficiency and reduced energy costs for the homeowner and the environment. When choosing a furnace, keep in mind that the best systems work hand-in-hand with proper ductwork, insulation, high-performance windows, and other measures that reduce air infiltration. For the most efficient furnace, choose the highest rated Energy Star product within your price range. When comparing heating systems, don’t forget to factor in installation costs, maintenance issues, and existing conditions.
Natural Gas Furnaces Gas-fired furnaces burn natural gas or liquefied petroleum in a clean burning system that can convert 95 percent of fuel into heat. Gas lines deliver fuel directly to the furnace.
Oil Heat Oil burns less efficiently than gas, converting about 90 percent of fuel into heat. The fuel must be transported from a supply facility and stored on-site in large tanks.
Heat Pumps Heat pumps lose efficiency when temperatures drop below 35 degrees Fahrenheit and must rely on a back-up system. The units are the most effective in regions that have nearly an equal demand for heating and cooling.
Electric Heat Electric systems require little maintenance since they generate heat without combustion. Although they offer 100 percent efficiency on-site, the power plant supplying the electricity does not. For example, a fossil-fuelled power plant may only deliver 4 units of electrical energy for every 10 units of fuel energy released.
Geothermal (Ground Source) Heating and Cooling Geothermal heat pumps, also called ground source heat pumps (GSHPs) are similar to ordinary heat pumps, but instead of using heat found in outside air, they rely on the stable, even heat of the earth to provide heating, air conditioning, and hot water.
Ever been inside a cave in the summer? The air underground is a constant, cooler temperature than the air outside. During the winter, that same constant temperature inside the cave is warmer than the air outside. That's the principle behind geothermal heat pumps. In the winter, they move the heat from the earth into your house. In the summer, they pull the heat from your home and discharge it into the ground.
The easiest GSHP installations are on lots with large areas of open land for the installation of the loops in shallow trenches (5'-6’ deep), but ground source heat pumps can also be used in tight, urban installations by drilling vertical wells.
GSHPs can be as much as 300% to 400% more efficient when compared to highly efficient furnaces. The most successful uses of GSHPs are in mixed climates like Pennsylvania that need both heating and cooling.
Radiant Floor Heating Systems Radiant hot water systems operate on water heated to around 95 degrees, which is much lower than the 120 degrees required by traditional boilers. Radiant heat works best with pex piping and a light-weight concrete wet bed. The wet bed absorbs and radiates heat better than other systems to help create a feeling of warmth with little fluctuation in temperature.
Photovoltaics Photovoltaic (PV) devices or “solar cells” change sunlight directly into electricity. Although systems require a relatively high initial investment, PV systems have no moving parts and are virtually maintenance free. Today’s manufacturers offer more attractive systems that can be installed on the roof, mounted on poles or integrated within existing structures. The increasingly availability of tax credits and rebates make these systems more affordable than ever before.
A green home should have a balanced heating, ventilation, and air-conditioning (HVAC) system. These systems push out stale indoor air and condition (preheats or precools) the outside air coming in for maximum efficiency and optimal air quality.
Modern heating and cooling equipment offers increased efficiency and reduced energy costs for the homeowner and the environment. When choosing a furnace, keep in mind that the best systems work hand-in-hand with proper ductwork, insulation, high-performance windows, and other measures that reduce air infiltration. For the most efficient furnace, choose the highest rated Energy Star product within your price range. When comparing heating systems, don’t forget to factor in installation costs, maintenance issues, and existing conditions.
Natural Gas Furnaces Gas-fired furnaces burn natural gas or liquefied petroleum in a clean burning system that can convert 95 percent of fuel into heat. Gas lines deliver fuel directly to the furnace.
Oil Heat Oil burns less efficiently than gas, converting about 90 percent of fuel into heat. The fuel must be transported from a supply facility and stored on-site in large tanks.
Heat Pumps Heat pumps lose efficiency when temperatures drop below 35 degrees Fahrenheit and must rely on a back-up system. The units are the most effective in regions that have nearly an equal demand for heating and cooling.
Electric Heat Electric systems require little maintenance since they generate heat without combustion. Although they offer 100 percent efficiency on-site, the power plant supplying the electricity does not. For example, a fossil-fuelled power plant may only deliver 4 units of electrical energy for every 10 units of fuel energy released.
Geothermal (Ground Source) Heating and Cooling Geothermal heat pumps, also called ground source heat pumps (GSHPs) are similar to ordinary heat pumps, but instead of using heat found in outside air, they rely on the stable, even heat of the earth to provide heating, air conditioning, and hot water.
Ever been inside a cave in the summer? The air underground is a constant, cooler temperature than the air outside. During the winter, that same constant temperature inside the cave is warmer than the air outside. That's the principle behind geothermal heat pumps. In the winter, they move the heat from the earth into your house. In the summer, they pull the heat from your home and discharge it into the ground.
The easiest GSHP installations are on lots with large areas of open land for the installation of the loops in shallow trenches (5'-6’ deep), but ground source heat pumps can also be used in tight, urban installations by drilling vertical wells.
GSHPs can be as much as 300% to 400% more efficient when compared to highly efficient furnaces. The most successful uses of GSHPs are in mixed climates like Pennsylvania that need both heating and cooling.
Radiant Floor Heating Systems Radiant hot water systems operate on water heated to around 95 degrees, which is much lower than the 120 degrees required by traditional boilers. Radiant heat works best with pex piping and a light-weight concrete wet bed. The wet bed absorbs and radiates heat better than other systems to help create a feeling of warmth with little fluctuation in temperature.
Photovoltaics Photovoltaic (PV) devices or “solar cells” change sunlight directly into electricity. Although systems require a relatively high initial investment, PV systems have no moving parts and are virtually maintenance free. Today’s manufacturers offer more attractive systems that can be installed on the roof, mounted on poles or integrated within existing structures. The increasingly availability of tax credits and rebates make these systems more affordable than ever before.
