LEED BD+C: Homes v2008
The Brooks Residence
LEED Platinum 2012
The below stakeholder perspectives address the following LEED credits:
WEc1.2, SSc2.2, EAc9.1, EAc10, MRc2.2
Goals and motivations
What were the top overarching goals and objectives?
The top three sustainability goals for this project were as follows:
- To keep as much of the existing house as possible.
- To merge the structure and mass of the house with the garden.
- In the garden our main priorities were to use native plants, re-use water, have no energy needs to maintain the garden, and to integrate the front vegetable garden into the community. We use the lowest tier of water for our garden and have many visiting critters. It has been quite successful. Humans need to interact with nature more and our house offers that opportunity along with a modern lifestyle.
What were the most notable strategies used to earn LEED credits?
The backyard is a formalized version of a natural world where native plants are both practical and aesthetically pleasing; conserving water and providing sustenance for native critters. In the back one finds a vegetated swale/ dry creek that fills seasonally with rainwater. 91% of plants on the entire property are native plants which are able to tolerate long spells of drought and thus rarely need to be watered. The other 9% of the plants are watered by the cisterns. Finally, a graywater recycling system is connected to every fixture in house except kitchen sink, dishwasher, and toilets. This water gets pumped to the riparian trees as well as the banana crescent.
This project conserves water and prevents storm water runoff from leaving the site using permeable surfaces and two rainwater cisterns that collect a total 900 gallons from 75% of the roof. About 500 square feet from East side of the home goes into a 600 gallon cistern and about 250 square feet of water collected from left side of old house goes into 300 gallon cistern. One cistern collects rainwater used to irrigate a fruit orchard and the other is an open air cistern with a habitat for fish and used to irrigate the cut-flower garden. Also, roughly 200 square feet of water collected from the roof over the master bedroom is directed into the rain garden in the back yard.
The ground floor expands vertically with plenty of daylight and ventilation to emanate a large indoor/outdoor space. Photo by Clark Davis.
The ground floor expands vertically with plenty of daylight and ventilation to emanate a large indoor/outdoor space despite the small square footage. The windows are strategically located at high and low areas of rooms to be in tune with natural air flow. In addition to South-facing fenestration, natural lighting is also provided by strategically placed solar tubes and skylights. This provides natural heating, cooling and ventilation throughout. All new walls are made of 2 x 6s in order to provide more space within the walls for better insulation. In addition, the insulation was verified by a third party to be installed per the QII Quality Installation of Insulation guidelines which ensures that the building envelope is truly insulated and sealed correctly. Combined with high efficiency appliances and an abundance of L.E.D. lights, the features make this house 52% more efficient than average new California homes. Additionally, the solar panels installed generate 85.2% of the annual electric load of the home.
Many materials used in the addition are re-purposed. The 100-year-old floor was restored and matched using a neighbor's old flooring. The staircase and bookshelves are all composed of re-used 2 x 4s from the existing walls that were removed. Where possible, materials have a high percentage of recycled content such as the exterior siding, bathroom tiles, concrete countertops, insulation and, foundations. Finally, 76% of the construction waste was diverted from landfills.
This staircase and bookshelf is made of re-used 2x4 lumber from the existing house. Photo by Clark Davis.
Aside from LEED certification, what do you consider key project successes?
The Brooks Residence is a prime example of how natural systems can be mimicked and used respectfully to help maintain the natural cycle of life in a sustainable and environmentally friendly manner. The project is serving its purpose as an educational home. For example, one of the walls inside the dining area is finished with plexi-glass instead of drywall so that one can see the different types of non-toxic or natural insulation options there are. Also, there is a vegetable garden in the front yard which encourages discussions with neighbors about growing organic food while building community and sharing food.
What key metrics best define the project's most significant savings or LEED-related successes?
Our home is now a Net Zero home, meaning we generate all of the electricity we need from our Solar system. This saves use about $200 per month on our electricity bill. Also, we re-use as much water as possible through our graywater system. This saves us about $50 per month on our water bill. The project shows how simple it is to have significant savings and a healthier lifestyle.
What one thing saved you or the project team the most time, money, or helped avoid an obstacle during the LEED process? What one thing cost you the most?
The main overriding strategy to preserve the existing house and re-use any materials from areas of demolition is what saved the project team the most time and money. It also helped us achieve many points in the Materials and Resources category. Specifically, we maintained all of the existing flooring and foundation. We also re-used the 2x4s that were removed from the demolished walls. Furthermore, we used attic space to create an additional bedroom, reducing cost and using existing space most efficiently. This attitude is what makes green building cost effective and affordable.
The most costly portion of our project was the graywater installation. This is due to the fact that it is a new concept and is not put into practice as often as it should be. We spent a lot of time and money re-adjusting the settings and location of the graywater lines. We also had to get many different experts to come on site and help us figure things out. In the overall scheme of things, the cost is not that high, but it is more expensive than simply sending all of our dirty water to the sewage system. It is, however, worth the cost to lower our water usage.
What was the value of applying LEED to this project?
In Isabelle's words: "LEED was like an invisible best friend who had more power than me and made my subcontractors take my requests seriously."
LEED and the USGBC are well respected and widely recognized organizations and standards for green building. Applying LEED to our project codified the importance of thinking through every little decision we made in the building process and viewing how it affected the big picture. LEED also legitimized all of the requests that may seem frivolous or insignificant to contractors. It was an empowering way to implement design strategies effectively in order to improve the performance of the building and reduce the negative impact we make on the environment. Specifically, the Q.I.I. process was fascinating and educational. Everyone involved learned about how insulation can be installed to make it work at its maximum efficiency and we can take this knowledge on to other projects, whether they will be LEED rated or not. Learning about the LEED principles is an overall benefit to the building and design community.
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