Thursday, April 8, 2010

An Idiots Guide to LEED for Civil Engineers

"Crap, this fruitcake architect is trying to make me use these fru fru stormwater techniques so he can have his "green building".  He just doesn't understand that its more complicated than just putting some pervious pavement down and installing one of those raingarden things!" - unknown civil engineer.

Does that sound like a civil engineer that you know?  Or maybe it sounds like you, if you're a civil engineer.  I may be beating this to death, but I hear over and over again from architects that the civil engineer is the hardest one to get on board with green buildings or that they contribute the least among the design team toward a LEED project.  It shouldn't be that way, civil engineers should be an enthusiastic and integrated contributer to the LEED process.

There are several ratings systems under the LEED umbrella now, but for the purpose of this post I am going to use the New Construction and Major Renovations (NC) system.  It's the most used and chances are if you are involved with a project, it will be under that system.  I often hear - "oh, you're the civil engineer, we need you for the stormwater credits (2 pts)."  If that's the civil engineer's only input on a LEED project you're missing a lot of opportunities for true collaboration and integrated design.  Civil engineers have the opportunity to provide input on 46 or more of the 110 possible points.  26 of those points are in the Sustainable Sites category and the rest are spread throughout the remaining categories.  Below is list of the credits that I believe benefit from the civil engineer's input, including a brief description of the practices and value that the civil engineer can provide.

Sustainable Sites
  • Prerequisite 1 - Construction Activity Pollution Prevention - This one is pretty obvious, even if the local regulations don't require you to do so, you should always be implementing erosion and sediment control plans in compliance with the construction general permit.
  • Credit 1 - Site Selection (1 pt) - Although its often not the case, civil engineers should always be a part of the site selection process.  Even beyond the LEED credits, a civil engineers input can often save money, time and headaches.
  • Credit 2 - Development Density and Community Connectivity (5 pts) - Again, this comes down to the civil engineer being a part of the site selection process.
  • Credit 3 - Brownfield Redevelopment (1 pt) - Civil engineers can be an integral part of the site rehabilitation process and can help to explain the pros and cons of developing a brownfield site and remove some of the uncertainty and fear in selecting such a site.
  • Credit 4.1-4.4 - Alternative Transportation (12 pts) - Transportation is what civil engineers do, so their involvement in this credit should be implied.  By providing for public transportation access in the form of site selection or creating new infrastructure, making traveling by bike more appealing, providing infrastructure and parking for low emitting vehicles and keeping parking lot sizes to their minimums, civil engineers can have a tremendous impact on the environmental footprint of a project.  
  • Credit 5.1-5.2 - Site Development (2 pts) - Protecting habitat area and maximizing open spaces can be accomplished with creative and efficient grading plans and site layouts, both of which should be designed by or with input from the civil engineer.  
  • Credit 6.1-6.2 - Stormwater Design (2 pts) -  This is the typical, give to the civil engineer credit, so the civil engineer's involvement is usually assumed.  The stormwater controls must address quantity and quality to standards that often exceed local standards.  To meet these requirements, the civil engineer should think out side the box and implement innovative best management practices such as bio-swales, raingardens, etc.
  • Credit 7.1-7.2 - Heat Island Effect (2 pts) - Civil engineers can help achieve these points for both roof and non-roof credits by recommending appropriate hardscape materials, providing shade from landscaping (new or existing), or assisting with greenroof specification and design. 
  • Credit 8 - Light Pollution Reduction (1 pt) - Although the responsibility for this credit falls primarily on the electrical engineer or lighting designer, civil engineers should participate with site light locations, limits of site areas that require artificial light, etc.
Water Efficiency
  • Credit 1 - Water Efficient Landscaping (4 pts) -  Civil engineers can assist with eliminating potable water use for landscaping by recommending and designing rainwater catchment systems, wastewater treatment systems for use in irrigation, and designing stormwater management controls (such as raingardens) that divert stormwater to landscape areas and provide for landscape water needs.
  • Credit 2 - Innovative Wastewater Technologies (2 pts) -  Civil engineers can accomplish this credit through option 2 by designing on-site wastewater treatment systems that treat 50% of wastewater to tertiary standards.
Energy and Atmosphere
  • Credit 1 - Optimize Energy Performance (7 pts) - There are 19 available points in this category, but civil engineers can help achieve up to 7 or more by participating in the site design process.  Building siting and orientation on the site can achieve 25% or more in energy savings and civil engineers can contribute by assisting architects, landscape architects and other engineers with creative and innovative site layout options.
Materials and Resources
  • Credit 2 - Construction Waste Management (1 pt) - If the project is on a redeveloped site or other site with existing pavement and/or concrete, civil engineers can write specifications allowing the reuse of the demolished concrete and asphalt in aggregate base, concrete mixes or asphalt mixes.  Doing this reduces raw material use and reduces the amount of waste that must go to a landfill.
  • Credit 4 - Recycled Content (1 pt) -  Civil engineers can contribute to the amount of recycled content used on a project by specifying fly ash replacement in site concrete, recycled asphalt pavement, recycled aggregate base and site appurtenances.
  • Credit 5 - Regional Materials (1 pt) - The largest ingredient in both asphalt and concrete is the aggregate, which is almost always meets the regional materials requirements of LEED.  While it is usually a small portion of the cost on a project, it can still contribute to the total nonetheless.  
Innovation in Design
  • Credit 1 - Innovation in Design (2 pts) -  Everyone on the design team should be trying to achieve innovation in design credits.  The ID credit was established by the USGBC to reward innovative design  and construction strategies that are not specifically accounted for the in the rating system.  4 points are possible in this credit and civil engineers should be able to provide valuable input on 2 or more of those potential points. 
Regional Priority
  • Credit 1 - Regional Priority (2 pts) -   Regional priority credits obviously vary by region, and a total of 4 points are possible.  Civil engineers should be able to provide valuable input on 2 or more of those potential points. 
Obviously, if you're a civil engineer you're probably not an idiot.  But, I think that civil engineers as a whole are missing opportunities to be an integral part of the LEED process, which is not smart.  Whether you are a civil engineer or another team member involved with a LEED project I would encourage you to look at the whole process and not limit yourself to a few credits.  In my opinion one of the most important parts of the LEED or green building process is the integrated design process, which hopefully solicits input from the entire team on all aspects of the project design and construction.

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