Ask Focus on Energy

A simple design/floor plan is best.

Great question! I’m going to answer your question in 3 parts, addressing each topic separately.

The short answer to the home design question is one with the fewest number of windows and exterior wall corners because they create energy loss dynamics on the interior and exterior. The longer and more detailed answer to that question goes like this:

• Consider how you can orient your home to take advantage of the sun’s heat and light. Keep in mind that natural surroundings such as hills and trees can provide shelter from winter winds.
• Windows can play a big role in overall energy costs depending on how much glass you desire. As a good rule for utilizing passive solar energy, design your home so that about 50% - 60% of the total window area faces due south. Reduce the area of nonsouth-facing window to the minimum required by building codes and install ENERGY STAR qualified windows throughout.
• Consider planting coniferous trees on the west side to provide some summer shading. A roof overhang on the south side also helps with summer shading.
• Additionally, as part of the design, place emphasis on building an airtight envelope. A tight home is more efficient, comfortable, and easier to maintain enhanced indoor air quality by using effective and quiet mechanical ventilation.
• In addition, make sure that you are installing the most efficient products and equipment in your new home. Buying only ENERGY STAR qualified appliances and lighting, installing a high efficiency hot water heater and furnace with an electronically commutated motor (ECM) and ensuring your central air conditioner is at least a SEER 15, will all go a long way in making your new home as energy efficient as possible. , and ventilation equipment to help provide high levels of indoor air quality
• Complement your heating/AC units with a programmable thermostat.
• This Web site has some information you might find useful as well.

Regarding the question about an energy efficient floor plan… the research I’ve done on this topic indicates that a functional floor plan incorporates these features:

• Efficient use of space in each room (use scale drawings of furniture early in the planning stage to assess layout)
• Minimal number of circulation paths which reduce useful space
• Proper progression from areas which are “public” to those which are “private”
• Appropriate use of passive solar gains and daylighting

A typical layout (ranch style home) would have living rooms, dining rooms, family rooms, and possibly a master bedroom on the south side. The kitchen, utility, and other bedrooms would face the north with a hallway running east/west.

With regards to your final question about energy efficient construction methods… that answer could go on and on in an effort to cover all the various possibilities. The one common thread of saving energy is in the details in the assembly of all the components/materials whether it is “stick-framed”, insulated concrete formed (ICF), structurally insulated panels system (SIPS), staggered wall, log construction, masonry, or something non-traditional like straw bale or cordwood wall construction. To aid you in learning more about energy efficient home construction, here are some reliable sources:

• Building Science Corporation
• Energy Efficiency and Renewable Energy Network
• Energy and Environmental Building Association
• Iris Communications, Inc.
• Focus on Energy New Homes  Program
• Green Built Home Program

In closing, no matter what design, floor plan, or construction method you decide on, consider having your new home built to meet the certification standards for the Focus on Energy New Homes Program. These homes are designed, built, tested and certified to ensure energy efficiency, combustion safety, durability and comfort. In fact a home built to the Focus on Energy New Home standard is as much as 10% more energy efficient than a new home built to code. In addition to the energy (and money) savings, other benefits include an enhanced ability to control moisture and indoor air quality, minimized drafts, properly installed insulation, sealed combustion (or power-vented) equipment, carbon monoxide detectors, and certification of the home’s efficiency based on performance testing upon completion of construction. A key piece to the Focus on Energy New Homes program are the consultants who are trained to work with your builder. The consultant is a third-party partner who certifies the home once it’s completed and will provide you with information on how to maintain your Focus on Energy New Home. The final result is a safe, durable, comfortable, and energy efficient home.

Published Tuesday, July 14, 2009