It used to be a matter of economics, not conservation. Children were taught to make sure lights were turned off. You used the warmth of your fireplace instead of running up the heating bill. And wasn't it a better idea to set up a fan than rev up the window-mounted air conditioner? The war generation taught their baby boomer kids to "waste not, want not" after rationing was the rule during WWII. While Americans still love to save money on utility bills, these days they are more interested in energy conservation and efficiency as well as living a green life.
If you are building a home from the ground up, energy efficiency should be a key consideration. And with the proper design and integrated plans, you can have a more comfortable and efficient living space than you may have ever thought possible. Interestingengineering.com's Christopher McFadden offers a number of considerations when building an energy-efficient home.
Before you even get started, however, do some research on your own regarding the design of your home-to-be, since all these energy elements can be integrated. Even though some look costly at first, when you factor in government rebates as incentives, your return on investment may not be a bad as you thought. "Energy consumption is, of course, significant to the initial design for every energy-efficient house," says McFadden. "It is important to acknowledge from the start that changing plans further down the line can be more costly than is necessary. Usually, planning departments for local authorities demand the plan or design for energy efficiency as a part of the submitted application."
Location and orientation are said to be the first considerations. Where is the house situated, what parts of the house get the most sun/most shade, and (assuming you are going solar) how can you maximize passive solar gain? "Simple directional and design-related tweaks can make a big difference to enjoy the summer sun without overheating the house," says McFadden. "Good design control of passive solar gain helps reduce heating loads during winter and cooling loads during the summer."
Made in the shade? Don't forget to engineer the landscape around your home as well, since it can also play a major role in energy efficiency. Planting deciduous trees on the west and south sides (depending on your geographical location) can help provide shade for the building during summer months, while in the fall the trees lose their canopies and allow winter sun to heat your home passively.
Planning your window design goes a long way in preserving energy, with low U-value frames and Low-E (low emissivity) glazing appropriately applied for the climate and direction. And airtightness, whether around windows, within walls or around your home's structure has an enormous impact on energy efficiency. Joints, sills, ducts, doors, and vents should all be as airtight as possible to reduce heating costs significantly. By the same token, ventilation in some areas is also vital, such as where mechanical items are located, along with wet rooms and kitchens. McFadden points out how ventilation systems have become increasingly sophisticated and often include heat recovery technology.
Heating design is not just a matter of choosing the right size system for your new home. Considering heating costs tend to comprise at least 50 percent of a home's energy bills, choosing the most efficient heating system is an essential design consideration, affecting the lifetime running costs of your home. Digital thermostats, weather compensators, and other state-of-the-art features can provide autonomous control of your HVAC system.
Hot water no longer needs be contained in cylinders or tanks. Tankless systems have been taking over residential construction, with many homeowners retrofitting their homes to save on utility bills. The size of the house, the number of occupants and the hot water capacity requirements of your home will ultimately dictate the design.
"Reducing the heat loss from building elements such as walls and floors is imperative for designing an energy-efficient home," says McFadden. "A good design of these composite components minimizes the u-Value and R-Value, which provides a passive and long-lasting benefit to the buildings' lifetime costs. There are many energy-efficient systems and materials available such as ICFs (Insulated Concrete Forms), thicker wall constructions, and roof insulations. Additionally, blown-in foam is also a well recognized, viable solution."
Source: Interestingenginerring.com, TBWS