During my internship last summer, I noticed a common trend in the types of energy-saving techniques owners were requesting in commercial buildings.  Many of the structures were designed to include LED lighting.  LEDs (light emitting diodes) have been around for many years, but high costs have prevented them from being used in large applications.  The most common places we used to see LEDs were on small electronics and in flashlights.  As LED technology has grown over the years, production costs have decreased while the bulbs have gotten much brighter.

LED lighting can last over twenty-five times as long as a normal incandescent bulbs and use only a fraction of the energy.  Therefore, many new buildings are designed to include LED lighting for all, or at least some, of its lighting needs.  While there still may be an additional cost compared to incandescent bulbs and fixtures, these costs can quickly be recouped by the low operating cost and due to the fact that LED bulbs rarely need to be replaced. 

While LED lighting has really taken off in commercial projects, LED producers have had trouble entering the residential market due to the initial extra cost and uninformed consumers.  The term “LED” has certainly become a household name recently, but the bulbs are only now starting to become affordable and practical.  Cree, one of the top producers of LED components, has just released a bulb that they believe will make the choice of switching to LED easy for residential buildings.  The new bulb consumes 84% less energy than a traditional bulb and can last for over 25,000 hours, which is about twenty-five times longer than a standard bulb.  As a recent article in Green Building News (LINK) explains, “The LED bulb is dimmable, has no mercury, lasts longer than a CFL bulb, turns on instantly and is energy efficient; it looks and lights like an incandescent bulb and is definitely the future in lighting technology.”  These new bulbs clearly outperform incandescent bulbs in many ways, but this still leave the issue of price.  The Cree bulbs cost anywhere from 9.97 to 13.97 depending on brightness, which is a dramatic drop in price compared to previous options.  Cree hopes to give consumers a reason to switch that will actually be the best choice for both the environment and their wallet, and a 10-year warranty should help make the decision easy for those on the fence about making the switch. 

Alternative energy proponents in Washington D.C. have passed legislation to make the city a model example that they hope the rest of the country will follow. (LINK)  Government agencies in Washington D.C. already receive fifty percent of their energy from wind-generated sources, but now one hundred percent of energy will be derived from wind-generated sources.  The District of Columbia Department of General Services claims that using one hundred percent wind-generated electricity is the same as taking 61,000 vehicles off the road for a year.

This is an interesting move, and makes me wonder if their commitment to wind energy will last.  The electricity is being purchased from a wind farm in Northern Virginia, and the contract is only good for one year.  After making a decision like this, it seems like it would be very difficult to go back to their old ways, and the contract will most likely be renewed.  The article does not mention what the wind generated electricity is costing the city compared to what they were paying before.  However, this definitely shows that the government is taking a step in the right direction by using energy sources that they try to force others to use. 

Sustainable practices do not stop with wind-generated electricity in Washington D.C..  The District of Columbia Department of General Services is taking steps to improve the city in other ways as well, and has created the Sustainable DC Plan.  Their main goal is to increase the use of renewable energy and decrease greenhouse gas emissions.  There are many “green jobs” available in Washington D.C. and the city already has over two hundred LEED and Energy Star buildings.  They are also bringing in companies such as Lucid Design Group and Honest Buildings to help discover and correct inefficiencies in energy consumption in both new and existing structures.

Growing Buildings

We often tend to focus on commercial projects when discussing what steps can be taken to construct green buildings.  However, green construction has also taken off in the residential market and there are a variety of different building products and techniques available.

One of the more interesting products I have come across lately (LINK) is called Hencrete.  Hemcrete is composed of hemp, lime, and water, and is being used to construct sustainable carbon negative building components.  The final product is a durable material that provides an airtight seal and can be used in many areas where traditionally framed walls would be used.  One advantage of Hemcrete is that it is very adaptive to changes in humidity and will not rot like a traditional wall if water is allowed to infiltrate the wall.  The biggest breakthrough with this new product is that it is carbon negative.  This means that there is more CO2 locked up throughout the growing and harvesting process of the hemp than the amount of carbon that is released during the production of the lime, which is used as the binder.  This is a very difficult accomplishment to achieve and could make Hemcrete a very popular product for using in future sustainable structures. 

Hemcrete can also be used for other building elements such as roof insulation and flooring.  Unlike traditional building materials, 100% of the product can be recycled when the structure is deconstructed.  Although a wall made out of plants may seem like a fire hazard, Hemcrete is actually fireproof due to the lime binder coating the plant material.

One issue with using Hemcrete is that it is currently priced much higher than traditional wall materials.  However, as the popularity of this product begins to grow and production costs decrease, Hemcrete could become a very common building product.  Unfortunately, the species of hemp required to make Hemcrete is illegal to grow in the United States, but the product has become extremely popular in Europe and other countries.  Advocates of sustainable construction are working to change laws to allow Hemcrete to be grown in the US, instead of having to import the product at high costs.

Below is a video demonstrating the production and application processes of Hemcrete:

We Can Reduce Greenhouse Gas Emissions, but Will We?

A Green Building Elements article (LINK) explains a study conducted at the University of Toronto concerning the reduction of greenhouse gas emissions.  Large cities account for the majority of greenhouse gas production.  The methods to reduce these emissions are readily available, but the problem is that they are difficult to implement.  Not every building can be torn down and rebuilt or retrofitted to operate more efficiently and have less of an impact on the environment.  Over time, buildings will have to be deconstructed due to age and can be rebuilt with sustainability in mind, but that will be a long and lengthy process.

The most logical and cost effective first step to take towards reducing greenhouse emissions is to educate citizens on practices they can adopt to help.  A combined effort of the majority of citizens in a particular city can have an enormous reduction of emissions.  The United States Environmental Protection Agency publishes a number of small steps (LINK) that citizens can take to reduce greenhouse gas emissions.  In the world of construction, we get caught up in how we can build something new and sustainable, but sometimes big changes can come from small improvements to items we already have.  For example, in our homes we can use energy efficient light bulbs, choose Energy Star products, use the thermostat wisely, add insulation, recycle, reduce water usage, and purchase green power.  Outside our homes we can commute in fuel efficient vehicles, use renewable fuels, or use alternative methods of transportation such as bicycles or public transportation (EPA 2013).

Existing buildings can help promote alternative means of transportation by adding bicycle racks or applying to have a bus stop closer to their building.  The idea of having all green buildings sounds great, but we will never be able to reach the lowest possible level of greenhouse gas emissions if people do not begin adopting sustainable practices into their daily lives.  Most buildings being constructed today are implementing at least some green building practices, even if they are very minimal.  Green building is continuing to grow at a rapid pace, and if it continues on this track, buildings will quickly be outperforming humans in efficiency.  If a large push is made now to encourage private citizens to use sustainable practices, the harm we are causing to the environment can be reduced much faster, by two of its greatest sources of pollution working together.

Are Green Buildings Risky?

One of the most common complaints about green buildings is that they are too expensive.  However, it has been proved that green buildings can be built for the same cost as a traditional structure, or if they do cost more, the extra cost will quickly equal out due to decreased operating costs.  One topic that is often not discussed is whether green buildings can have more problems than a traditional building.

An article published by the Associated General Contractorsof America (AGC) addresses other issues that owners and contractors may need to consider before deciding to build a green building.  The main focus of the article is that using new construction methods and materials increases the risk of potential problems.  As stated in the article, “Simply put, departing from the ‘tried and true’ often means increasing the risk of building failure.” 

One of the main risks involved with green buildings is the potential for moisture and mold issues.  Many green buildings encourage the introduction of outside air to achieve indoor air quality credits, while traditional buildings emphasize dehumidification.  Large amounts of outside air can lead to moisture and mold issues soon after the building is constructed.  A variety of other green building practices can also lead to moisture problems.  Vegetative roofs stay moist and can leak into the structure.  Many green buildings focus on insulation rather than repelling water.  Also, the increased insulation can change the dew point location in walls and increase condensation.  Recycled materials may not shed water as well as traditional materials.  Finally, some methods to improve air quality, such as “building flush out” may introduce an excessive amount of moisture into the building.

Another risk involved with green building is the number of new building products being introduced that claim to be sustainable.  Many of these new products have received a limited amount of testing and may fail to meet their advertised performance levels, compared with proven materials found in other buildings.  This could result in a shorter lifespan of the structure than anticipated and possible safety concerns.

All of these issues should be addressed when designing and constructing green buildings.  If any of these problems do occur, the owner may end up with a useless building.  This could result in a legal battle between the designer, owner, and contractor.  Repair and legal costs could quickly outweigh the money saved in operating costs by building a green building.  Therefore, special care should be taken to be sure that the building will be able to perform either equally or better than a traditional building.  The article recommends three steps to help achieve this goal.  First, a Climate Design Criteria should be developed to encourage the best practices for moisture control.  Next, a Green Building Risk Management Plan should be created to provide guidelines for building the project, as recommended by a variety of experts.  Finally, past projects should be used to determine what practices worked and failed.  Green building is growing at a rapid pace, and while it is wonderful for the environment, we must remember to maintain a high level of building quality so they can be used for many years into the future.