One would think that living in a brand new home would be the epitome of modern living. Wouldn’t a brand new home be healthy to live in? Wouldn’t it be durable enough to last for 100 years and be the most comfortable home available? Shouldn’t it offer the lowest possible energy costs? Wouldn’t it be healthy for those living in it and friendly to the planet? In this day and age, don’t building codes ensure all this?

Sadly, no. All too often home buyers either assume that a new homes means the highest standards of building or they accept one that is unhealthy, destined to fail, has high energy costs, annoying drafts and uneven temperatures – in other words – a home that sucks! But it doesn’t have to be this way. Increasingly builders are offering homes that meet a higher standard than current building codes. These builders are striving for a “green building.” But the claim that a home is a “green” home can be vague and is often overstated. Smart homebuyers looking for a true green building should be sure to purchase one that is certified.

There are many voluntary certification programs that pick up where building codes leave off. You may have heard of Leadership in Energy and Environmental Design or LEED. A high LEED score means that your new home or building has above average energy efficiency along with a host of other features to improve comfort,health and sustainability. There are other certification programs, such as the Living Building Challenge, Earth Advantage, and GreenStar, that require similar sets of environmentally-friendly features to ensure that a home will be comfortable, healthy, resource efficient, and energy efficient. Most of these programs require ENERGY STAR Homes certification. This is a great first step and improves energy performance 10-20 percent above typical building codes.


Energy performance is the most important feature of a green building because the energy used in a home increases the cost of ownership and creates a significant amount of greenhouse gas pollution – the principal cause of climate change. So, it’s no surprise that energy use occupies the central position for all green building certification programs. The ultimate in green buildings are those that take energy efficiency all the way to zero. As with other green buildings, these homes should be certified by an independent third-party. Several organizations offer zero energy certification, based on the HERS Index or the Energy Performance Score. Among all the elements of green building, energy-saving features represent the best opportunity for financial return and reducing greenhouse gases.


Many regions suffer from severe water shortages, pipe drinking water hundreds of miles, and deplete rivers and streams to satisfy an ever-growing appetite for fresh water. In many places the stress on clean water supplies is reflected in the rising cost of water utility service. Using less water also reduces the large amounts of energy used to treat fresh water for consumption and for treating waste water so it can return to the natural cycle.

Green building standards address these issues primarily by attempting to reduce water waste. Using water wise landscaping practices and water-efficient appliances, such as dishwashers, clothes washers, low-flow toilets, low-flow showers and faucets go a long way towards accomplishing this goal. When occupants use less hot water, energy savings are a bonus benefit that helps move the home closer to zero energy. In fact, reducing hot water use in these ways is extremely cost effective and among the easiest strategies to implement because they simply require careful selection of plumbing and irrigation products.


Of all the benefits of a green building, thermal comfort is the most immediate and direct. The same features that save energy (air sealing, insulation, and properly installed heating and cooling systems) also make the home more comfortable. Drafts are gone. Cold spots are eliminated. Conditioned air (both heated and cooled) reaches every inch of the home. The result is a home that maintains a constant, even temperature all year long. These benefits come as a result of the home’s energy efficiency – and the closer to zero a home is, the more benefits the homeowner will enjoy.


Many of the materials used in construction and interiors have some level of toxicity. Volatile organic compounds (VOCs), brominated fire retardants, formaldehyde and other chemicals are still allowed in most of the US, although they are strictly regulated in Europe. Certified green buildings avoid as many of these substances as possible. One program, the Living Building Challenge, identifies chemicals that should not be used in homes on its Red List. Most programs discourage or forbid combustion of fossil fuels for heating and cooking.

In addition, certified green homes are tightly air sealed, so they exclude most outdoor air pollutants, smoke, pollens, radon from the soil, and moisture that can lead to mold problems, as well as excluding outside noises. Zero energy homes strive for the highest level of air sealing of any green building. To top it all off, most certified green buildings – especially zero energy buildings – have ducted fresh air systems that provide a constant supply of fresh filtered air, manage moisture, remove particulates and other outdoor air pollutants, and expel indoor air pollutants and odors resulting from daily activities. The result is a healthier home free of most common allergens and toxic chemicals.


Moisture is the biggest enemy of any structure. Homes must be protected on the outside from the elements and on the inside from water vapor generated by the occupants. All green building programs require durability measures that protect homes from rain, snow, and runoff. Zero energy homes and some advanced green homes take controlled ventilation a step further by using heat recovery ventilation or a fresh air system.

Resource Conservation

All human activity draws materials from nature. These include lumber, stone, iron, lime, silica, gypsum and even petroleum products. Extracting and processing these resources to create usable building materials requires vast amounts of energy and freshwater, and releases large amounts of carbon into the atmosphere. While Earth can supply all these resources, there are limits. Making the best use of these limited resources is absolutely essential if humans and natural ecosystems are to survive. The best green building certification programs identify many ways to do this. Minimizing construction waste, using building materials with high levels of post-consumer recycled content or rapidly renewable sources and buying locally-produced materials whenever possible are some of the ways green building programs promote resource efficiency. Most green building programs, and especially zero energy programs, encourage smaller homes that consume fewer construction materials.

Zero Energy Building is the Ultimate in Green Building

As a label, green building is often loosely thrown around by sales people. Even when a building has some kind of green certification, it may be quite broad and cover many aspects of design and construction. And even though energy efficiency is the one element of green building that is routinely evaluated through performance testing, such as blower door measurements, and confirmed through LEED scores, green buildings don’t always give highest priority to low energy use and low carbon emissions. But, zero energy use and zero carbon emissions are essential for buildings to be truly green. And, it is precisely this high level of energy efficiency that provides many of the green building benefits described above. With a certified zero energy building you can be confident that you will eliminate carbon emissions, improve comfort and health, reduce the cost of ownership, provide peace and quiet, reduce resource use (especially in the case of smaller homes), and build a structure that will last – making certified zero energy homes the ultimate in green buildings.