permeable

Exploring Permeable Pavement Options for LEED Projects

Posted on by abrahamwien18

By Julie Lundin, NCIDQ, LEED AP ID+C, Principal
Emerald Skyline Corporation

As business owners and designers of our renovation project in Boca Raton, there are many decisions and variables involved in the design of both the building and the site. This project is a LEED registered project which impacts our design decisions and materials selected to incorporate sustainable goals. It gave us the opportunity to explore sustainable pavement options rather than the traditional blacktop used in most projects. The size of the project, location, cost, financial incentives to explore alternatives, and local city requirements all impact decisions to be made. When a pervious pavement is used in building site design, it can aid in the process of qualifying for LEED Green Building Rating System credits.

Leadership in Energy and Environmental Design (LEED®) is a rating system developed by the United States Green Building Council (USGBC) to evaluate the environmental performance of a building. LEED is a voluntary, consensus-based national standard for developing high-performance, sustainable buildings.

LEED provides a framework for evaluating building performance and meeting sustainability goals through five credit categories: sustainable site development, water savings, energy efficiency, materials selection and indoor environmental quality. It should be noted, however, that LEED points are not gained directly by the use of a product but by meeting a specific sustainability goal of the rating program.

Pervious pavement options can contribute to many LEED categories including: Sustainable Sites, Water Efficiency, Materials and Resources, and Innovation in Design. Pervious pavement choices are unique and innovative ways to manage storm water and as a method of delaying roof runoff from entering city sewers. Considering these gives environmentally conscious business owners options to use in parking lots and walkways. When they are used in the building site design they function like storm water retention basins and allow the storm water to infiltrate the soil over a large area and recharge the groundwater supplies.

Why consider pervious pavement options?

Storm water is polluted

  • Oils and greases
  • Metals
  • Sediments
  • Fertilizers

Sustainability Factors

  • Low-Impact Development
  • Pollution Treatment
  • Recharging Ground Water
  • Tree Protection
  • LEED Requirements
  • Cool Communities

Meets LEED Requirements

  • Reduce Storm Water Runoff
  • Improve Storm Water Quality
  • Reduce Urban Heat Islands
  • Recycled Materials
  • Regional Materials

Description of specific credits where pervious pavement can aid the business owner or designer include:

 LEED Credit SS-C6.1 Storm Water Design – Quantity Control

LEED Credit SS-C6.2 Storm Water Design – Quantity Control

The intent of these credits is to limit disruption and pollution of natural water flows by managing storm water runoff, increasing on-site infiltration and eliminating contaminants. Pervious pavement can contribute to this credit by reducing storm water flow by allowing water to soak through and infiltrate to the ground below. Pervious choices can also reduce the pollutant loads by filtering contaminants as the water is transferred through the pavement.

 LEED Credit SS-C7.1 Heat Island Effect- Non-Roof

 Pervious pavement acts to reduce the heat island effect by absorbing less heat from solar radiation than darker pavements. The relatively open pore structure and the light color of pervious pavements store less heat, therefore, reducing the heat reflected back into the environment and helping to lower heat island effects in urban areas. The heat island effect can be further minimized by the addition of trees planted in parking lots. The trees offer shade and produce a cooling effect for the paving. Pervious pavement is ideal for protecting trees in a paved environment (many plants have difficulty growing in areas covered by impervious pavements, sidewalks and landscaping, because air and water have difficulty getting to the roots). Pervious pavements or sidewalks allow adjacent trees to receive more air and water and still permit full use of the pavement.

LEED Credit WE C1.1 Water Efficient Landscaping

 The intent of this credit is to limit or eliminate the use of potable water, or other natural surface or subsurface water resources available on or near the project site, for landscape irrigation. The gravel sub-base under pervious pavements can be used to store storm water for irrigation, helping to satisfy this credit. If no irrigation is required for a project, two points may be earned.

LEED Credits MR-C4.1 and MR-C4-2 Recycled Content

The intent of this credit is to increase the demand for building products that have incorporated recycled content material reducing the impacts resulting from the extraction of new material. Almost all ready mixed concrete contains recycled materials in the form supplementary cementitious materials (SCM) such as fly ash, slag, or silica fume. The use of SCMs or recycled aggregate in pervious concrete or base material contributes to recycled content needed for this credit.

LEED Credit MR-C5.1 and MR-C5.2 Regional Materials

The intent of this credit is to increase demand for building products that are extracted and manufactured locally, thereby reducing the environmental impacts resulting from their transportation and supporting the local economy. The majority of materials in pervious concrete and pavements are considered regional materials. In addition to aiding in gaining LEED certification points, pervious concrete can provide a safe and durable surface for most pavement needs. Light colored pervious pavements require less site lighting to provide safe night-time illumination levels, whether on parking lots, driveways, or sidewalks.

Types of Pervious Pavements

  • Porous Asphalt (Blacktop)
    • Low Cost
    • Effective Porosity
    • High Maintenance – Biannual cleaning to prevent clogging
    • Does not allow for plant growth
    • Contributor to heat island effect but better than standard ashphalt
    • Alternative for large projects
  • Pervious Concrete
    • Same concept as porous asphalt, except it is concrete
    • Easy to order and have installed
    • Light in color and not contribute to heat island effect
    • Higher Cost than Asphalt
    • Request use of local or reclaimed aggregates
    • Use highest amount of Fly Ash and/or Slag (both are reclaimed waste products)
    • Requires cleaning to prevent clogging
    • Can serve as a retention basin for storing rainwater during a storm
  • Pervious Block Pavers
    • Many different types on the market
    • Can look like traditional pavers for aesthetics
    • Filled in with grass or gravel
    • Allows for plant growth
    • Pavers are pricey
    • Installation requires laying of individual small blocks
    • May settle or become misplaced after use
  • Drivable Grass
    • Unique product
    • 2” x 2” mats that are more affordable individual pavers
    • Good infiltration for grass growth or ground cover
    • Plants remain cooler and receive uniform watering
    • Greener parking surface than other plantable systems
    • Low maintenance
  • Plastic Grid Systems
    • Made of recycled plastic and fully recyclable themselves
    • Low maintenance
    • Easy installation
    • Can provide a fully sodded surface if desired
    • Use only appropriate for light or occasional use parking lots

Decision making is a critical process for any project. Well informed choices and decisions can help keep a project timeline on track. Decisions in all areas including design and specifications need to be clearly and fully described. There should be at least three options to choose from that include how, what, where and how much? All the implications and impact of each option must be considered. Will it delay the project? Will it increase the cost?   A LEED project also needs to incorporate the analysis of products and design and their sustainable impacts. We are considering 3 categories of pervious pavement products for our project; pervious concrete, pervious block pavers, and drivable grass. With the ever evolving development of sustainable products, there may also be a hybrid solution available that will meet all of our project goals.

http://www.epa.gov/region02/njgiforum/pdf/08justice.pdf

http://www.perviouspavement.org/benefits/leed.html

http://www.100khouse.com/2010/12/08/permeable-pavement-options-for-leed-projects/

LEED Project Update – Build Better Codes

Posted on by abrahamwien18

JulieBy Julie Lundin, NCIDQ, LEED AP ID+C, ASID
Founder, Director of LEED Process Management for Emerald Skyline Corporation

Emerald Skyline Corporation, in conjunction with Golden Spiral Design, is designing, renovating and repurposing an unoccupied industrial building located in Boca Raton, FL. This distinctive commercial building will include many sustainable features with the intent to obtain LEED (Leadership in Energy & Environmental Design) certification from the USGBC. LEED certification recognizes performance in five key areas of human and environmental health: sustainable site development, water savings, energy efficiency, materials selection and indoor environmental quality. It is a whole-building approach to sustainability which will enable us to save on utilities and maintenance while improving the well-being of our personnel and our clients.

LEED is a third party certification program and the nationally accepted benchmark for the design, construction and operation of high performance green buildings. The LEED Green building rating system encourages and accelerates global adoption of sustainable green building and development practices through the creation and implementation of universally understood and accepted tools and performance criteria.

We continue to modify the design of the building in preparation for submission to the City of Boca Raton Development Services Department. In preliminary meetings with the Planning Department and Traffic Engineers it was determined that the building occupancy will require a minimum of 8+ parking spaces per the existing (dated) Municipal Codes. The limited space for parking on the site will make it difficult to meet these requirements.

Based on our plans intended use of the building, our parking needs for the building are much less than the codes require. Both Emerald Skyline and Golden Spiral employ sustainable business practices which encourages personnel to spend the majority of their time working remotely.

Boca Raton’s current parking requirement is not congruent with sustainable thinking which encourages “hotelling” or “hot desking”, the use of public transportation and alternate commuting methods such as riding a bicycle. In meeting with representatives the City of Boca Raton, they have indicated that they might help us on this initiative as they have special exemptions for sustainable buildings. Our goal is to have the minimum number of spaces necessary to satisfy our needs.

Further, as a LEED certified project, our design goals are to minimize paved surfaces as solid surfaces contribute negatively to our environment. Our vision is to utilize permeable pavers for the parking spaces we will have on-site. Here is why:

Permeable pavers help the environment by:

  • Improving the quality of storm water runoff as it is returned to a ground water source;
  • Providing a solution to soil erosion by allowing grass to grow within the spaces of the block and blend in with the surroundings.
  • Reducing or eliminating storm water runoff, decreasing flooding and relieving sewer system demands while still providing a sturdy surface for vehicle and pedestrian traffic; and
  • Reducing heat that is transmitted into the atmosphere from hot pavement by providing a vegetative and reflective surface.

Rating systems like LEED are critical proving grounds for building strategies that address an inclusive set of risks that require our attention beyond fire safety, disability access and other crucial areas.

Building codes have presented barriers to the application of more forward-looking technologies, materials and methods. Building green requires a multi-disciplinary approach to break down the walls between planning, design and construction. The existing codes have been a factor in the business-as-usual construction process. As the viability, cost-effectiveness, and many benefits of green building continue to prove their worth, code safety needs to evolve to incorporate a broader scope of responsibility that are now expected. We are hopeful that building codes, including those of Boca Raton, will begin to encompass sustainable building needs.

 

USGBC – Build Better Codes

http://www.usgbc.org/Docs/Archive/General/Docs18641.pdf