MASSEY HOFFMAN ARCHITECTS

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2 Green is Simply Good Practice How Good Design Strategies and Construction Practices can Achieve a LEED for Homes Certification Often it seems that the motivation for building green comes from the desire to do the right thing, or to be a better steward of our limited resources. These worthwhile objectives may be rewarded with lower energy usage and a cleaner environment, but at what cost? What was learned in the course of this recent renovation project is that with care, standard practices in design and construction make achieving a LEED for Homes certification obtainable. In general, good building design practices will get you most of the way. Obtaining LEED certification does not require exotic and costly measures. It is the thoughtful use of materials, systems and resources that makes it achievable. While the LEED project checklist formalizes the 8 LEED credit categories, it is good planning, follow through during construction, and total project team awareness that results in a LEED home that is healthier, more comfortable, more durable and more energy efficient than the same house built to the required building codes. 1. Building and Site This project was the complete renovation of a 1930 s era Georgian style brick bungalow with over 8,000 square feet of livable space located in Wilmette, Illinois. We were tasked with restoring the existing building envelope while designing completely new interior spaces with appropriate material finishes, conveniences and building systems of a 21 st century custom single family home. The Owner inquired about LEED certification based on the premise that re-use of an existing building was the most obvious act of sustainable construction. The initial reaction was that certification was possible but would surely stress the already tight project budget due to the size of the structure and the scope of the

3 renovation. The Owner determined that the goals of the LEED program paralleled their own goals for the kind of home construction and living environment they desired. Accepting this challenge, we began the design phase with the goal of achieving a LEED Silver certification. The LEED credit calculation was initially established based on the total livable square footage and the total bedroom count of the existing house. These givens actually created a significant credit deficit that the project team needed to overcome. However, the fact that this was an existing structure in a well established neighborhood also offered the first LEED credits for location/proximity to urban infrastructure and site stewardship. Further as a previously developed site, it provided additional credits for plant and tree preservation, site rehabilitation/removing invasive plant species/erosion control and development of a basic landscape design again, standard design practices that were in sync with the Owner s decision to invest in making this their home. 2. The Design Strategy Site and landscape design are required components of LEED certification. With these criteria met, it was the design and construction practices that were fundamental to creating a sustainable building. This included the building systems, materials and products, and construction. While the existing building shell was to remain intact with the exception of window replacement, it was astonishing to discover that the key building features; exterior brick walls, wood roof structure and cement tile roofing earned no LEED credits for re-use or restoration. It is possible that these components may earn LEED credit as

4 reclaimed material. That said, selective demolition and disposal offered material resources credit for debris recycling and construction waste control as did re-using and leveling the wood floor and roof structures to minimize the use of new wood structure. Not only did these strategies net LEED credits, they provided financial benefits to the Owner by re-using material rather than replacing them. The existing building shell was also an asset as it reduced cost and time needed to construct a fully insulated building envelope; key to obtaining LEED credits for improved energy performance and air quality control. The foundation was excavated to apply waterproofing, rigid insulation and perimeter drain-tile. The exterior brick was tuck-pointed, damaged masonry was replaced, all single pane wood windows were replaced with Energy Star rated low-e, argon filled insulated glass units and interior wood framing was added to the perimeter walls and along with the roof rafters, filled with open-cell spray-in foam insulation. These improvements were all necessary to meet current building code requirements as well as satisfy LEED standards. Improving the energy performance and quality of the living environment also earned numerous credits. Standard practices such as covering return ductwork during construction, venting exhaust directly to outdoors, providing only ducted return air, and insulating hot and cold water piping provided credits. In addition, the renovated building envelope worked in conjunction with the new high efficiency furnaces with the upgrade of adding Energy Recovery Ventilators to each furnace and high SEER air conditioning condensers to obtain additional credits for indoor environmental quality. While not standard, this upgrade in equipment provided improved performance and long-term financial benefit.

5 Just as equipment selections earned credits, material finishes and products provided opportunities for further credits such as material resources. Ranging from Energy Star rated kitchen and laundry appliances, floor and wall tile with recycled content, locally sourced wood, reduced flow plumbing fixtures, no VOC paint and finishes, low voltage dimming switches and light fixtures to applications such as durable materials in bathrooms and laundry and installing fireplace doors, the requirements are not limiting or imposing on the design. Rather, these green products are actually obvious and standard components in residential design; thoughtfully selected to compliment the design without added costs and satisfy LEED requirements. In all cases, they are a benefit to the project and the livability of the home. 3. The Construction Methodology While the performance of the building and material/product selections were specified and detailed in the architectural drawings, the construction team needed to be aware of the project LEED checklist and buy-in to the effort to produce a LEED certified building. This required very few measures beyond normal project supervision and construction observation but it was essential to understand that construction methods and management earn credits. The contractor had to commit to verify that the products and materials were exactly as specified. Testing and documentation were key to qualifying and confirming that the specifications and design were constructed to achieve the desired results. This was a requirement for LEED certification. However, the contractor went above and beyond by having a preliminary Blower Door test performed at a critical point during construction to ensure that the construction would meet or exceed the

6 performance criteria. Achieving long term savings from improved building performance in terms of reduced energy consumption and better indoor air quality easily offset the cost of the test. 4. A LEED for Homes Project With the project now completed, the benefits of a LEED certified home will become apparent to the homeowner. On the initial premise that renovating rather than razing the existing structure was the right thing for the environment, the Owner now has a house designed and finished with the spaces they always wanted to live in; reflecting both the inherent character of the original structure and highlighting their individual aspirations for what their home could be. In addition, this house is a structure built with health, energy and environmentally responsible building systems that have minimized its footprint on the environment without reducing the original building by even one square foot.

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