Examines 16 important qualities that green building materials should strive to achieve and that builders need to weigh during the materials selection process of a project. A well planned green building material selection process can help to ensure the best solution for a given project with given goals and constraints peculates up through the decision process.
The phrase “Green Building” is used a lot, but it is often less understood what it really means. Understanding what it means is made more difficult because it means many various things and its meaning has several dimensions. Green buildings, also known as sustainable buildings, certainly aspire to improve energy and water efficiency for example, and to lessen their impact both during their construction and during their service. One way of defining them in broad terms is that they are built structures that are designed, built (or renovated), and operated in an ecological and resource-efficient manner. Many also include how the building can be re-cycled at the end of its service life as well. In addition there are other considerations, such as the quality of the built environment… i.e. is it healthy etc.
When one considers that buildings use well over one third of all the energy consumed in the US; that building site debris constitutes almost one third of all landfill waste in the country this subject acquires the full dimension of just how important it is to begin to get this right.
To read about six important green building site preparation best practices see our related post: “Six Sustainable Site Planning Fundamentals“.
What Makes Green Building Materials Green?
This post, which summarizes Environmental Assessment and Specification of Green Building Materials by Lynn M. Froeschle, focuses on what kind of qualities a material should have in order to be green. It seeks to answer the following question: What is a green building product or material? This is an important part of the larger subject and understanding this is critical to a larger understanding that encompasses all the aspects of what goes into making a building project green – or in other words sustainable.
Once again the answer is not as easy as it may at first seem. A lot of competing priorities go into deciding what is the greenest material choice for a given project; priorities that are sometimes contradictory and that must be carefully weighed against one another. Each single project will be driven by its project goals and environment, which will, in turn in part determine what material choices are ultimately made. Factors such as whether it is new construction or a renovation; whether it is an undeveloped site or is an already built site; what the ordering in terms of importance for a given project various objectives such as: energy efficiency, water efficiency, indoor air quality, local sourcing, and so forth.
Each designer/architect and any engineers and/or builders involved in this process need to develop a good plan that clearly outlines their design criteria and then once this is clearly understood to evaluate the building material options in light of how they help achieve the projects objectives.
In general however green building materials will have certain commonly recognized qualities that factor into their greenness index – so to speak – and into how sustainable these materials are. These are:
2. Materials that emit few if any volatile organic compounds (VOCs) are inherently greener than materials that emit VOCs. VOCs are the main cause of unhealthy indoor air quality. It is especially important to avoid materials that use (and emit) ozone depleting chlorofluorocarbons (CFCs) (such as certain foam products)
3. Similarly look for materials that can be assembled or installed with minimal use of VOC producing compounds, such as many types of glue for example. Look for materials that can be mechanical attached and that do not require VOC producing bonding or coating.
4. Recycled content. Does the material have recycled content in it? Does it have post-consumer recycled content? Generally speaking materials that incorporate recycled content into them are more sustainable than those that are made exclusively from new raw materials.
5. Materials that can be produced using more resource efficient manufacturing and refining methods are going to be greener. Look at how much energy, water and other resources have gone into making the product under consideration. This embodied energy and resource content or footprint is very important in determining how sustainable it is.
6. Local sourcing – look at how far the product needs to be sourced from. The greenest of green products that must be transported half way around the world is likely to be a lot less green than an alternative product that can be found regionally – even if that does not have as green credentials as the first. The energy costs of transporting things over long distances, quickly adds up and overtakes other considerations.
7. Recyclable materials. Look at building materials from the perspective of how easily they can be re-cycled
8. Sustainably farmed or produced products. Look for renewable natural materials harvested from sustainably managed sources and that if possible have an independent certification.
9. Can the material or component be reused or salvaged when the building has reached the end of its service life. Ultimately choosing materials or components that are designed for reuse will help promote sustainability even more than recycling does, because re-manufacturing is avoided.
10. Try to use materials that maximize energy efficiency during normal building operation. Maximizing energy efficiency of a building or other facility is perhaps the single most important goal for sustainable building. Consider that buildings account for well over a third of all energy consumed in the US, and their energy usage – mostly for space heating and cooling – dwarfs other uses – including transportation usage.
11. Water Conserving. Look at materials (and techniques) that can conserve water resources including storm runoff. Grey water systems for flushing toilets are an example of this.
12. Durability. A green building usually (though not always) should be designed and built to last. And materials that need less frequent replacement generally speaking tend to be greener than those that are not as durable.
13. Look for materials that inhibit moisture accumulation in dead interspaces in the building. This helps prevent biological contamination of a structure with molds for example that can lead to poor indoor air quality issues and even serious health issues if not addressed.
14. Look for materials or component systems that can help to improve indoor air quality (IAQ).
15. Easy to maintain materials that can be maintained without using toxic products, such as harsh cleansers that emit VOCs. Can it be kept clean with nothing more than say soap and water?
16. Finally of course these materials must be affordable. A green material that forces a project to go over budget may not be advisable. It is important to not overlook this bottom line perspective when comparing alternatives. Whatever choices are made the total life cycle cost of the material – and it is important to look at it in this way if the objective is to build in a sustainable manner – the total life cycle cost is going to be very important.
Finding the Green Building Material Solution for your Building Project
There are quite a number of things to consider and each project needs to find its own happy balance between various tradeoffs. In general the process needs to begin with a research phase.
Research various options, including gathering materials and information directly from various kinds of rating agencies, as well as manufacturers or upstream producers. Research your various options looking for things such as: material safety data (MSD); indoor air quality (IAQ) data if that is available; any environmental statements or independent sustainability certificates, such as sustainably grown and harvested wood for example; percentage of recycled content, especially post-consumer content; find out how locally the material can be sourced from; and also look for any warranties and statements of how durable the product or material is; and of course how much it costs.
When looking at data sheets and statements it is important to take everything with a grain of salt and when possible to try to get independent confirmation that can back up data from a manufacturer or producer.
After gathering as much research data as is feasible and exploring various alternative options that are available the next step is to begin evaluating the alternatives. Often this will involve even more research – to get independent data that backs up a manufacturers own statements, for example. Having data from independent laboratories and rating entities can be very helpful in the evaluation phase, but it is important to also understand that as markets, technology etc. change materials and component products may also change as well. If there is some doubt; this can usually be cleared up by requesting letters of clarification from manufacturers.
By doing good research and evaluation the selection process has a higher degree of confidence than it would otherwise.
Our related post: “Return on Investment for Green / LEED Projects“, looks at ways that green buildings provide long-term savings and solid returns on investments.
© 2011, Chris de Morsella. All rights reserved. Do not republish.