The Residential Green Building Committee gathered on October 16th, 2017. We had a guest presentation from John Rockwell, of Zehnder America. He was here to help us understand proper and efficient mechanical ventilation standards for buildings.
He started off by emphasizing the importance of making buildings airtight, and not just jumping straight to insulation measures when looking for fixes. He continued to explain that air movement is the primary goal, because of all the contaminants and toxins buildings can have inside (in the rugs, furniture, etc), and we need that to move through.
John went on to explore the different ventilation options: Exhaust Ventilation, Supply Ventilation, Balanced Ventilation and Heat Recovery Ventilation. The conclusion was that the Balanced Ventilation is highly recommended in conjunction with an HRV or ERV, over Supply Ventilation for example, which pulls outside air into the home, while the stale air exits the home through building envelope leakage. The HRV serves as a heat exchanger between the fresh and stale air, and they actually have a higher heat recovery efficiency than an ERV. The reason being is because the HRV isn’t focused on moisture transfer like the ERV’s are, so there are more resources being dedicated to the heat exchange.
John explained that when choosing to implement an HRV or ERV, it is important to think about climate, occupancy, and humidity levels. Not only are all these ventilation methods supposed to be efficient for overall energy use, but they are also supposed to enhance the health and comfort of the inhabitants within the building.
John taught us a lot on Monday night, and was an extraordinary teacher for all of us! We hope you will join us at our next Residential Green Building Committee meeting to continue the conversation and learn from one another.
The Residential Green Building Committee (RGBC) met on May 8th, 2017. We had a guest presentation from Stephanie Horowitz, Managing Director of ZeroEnergy Design. ZED is a green architecture and energy consulting firm, working in the fields of architecture, mechanical engineering, and finance.
With a strong 7 person team, ZED is committed to designing homes and buildings that use 50% less energy than building code requires. Stephanie explained that most of their project makeup consists of single-family homes, compared to multi-family homes. They are also on track for the 2030 Challenge, which they started tracking in 2010 for their own projects.
When designing for most energy efficiency for a building, ZED prioritizes the building envelope first, followed by systems, and then renewables. ZED uses PHPP (Passive House Planning Package) for energy modeling of their custom home projects, but not all projects are expected to earn Passive House certification. The Energy Use Intensity (EUI) values for ZED’s completed projects are published on their website.
Stephanie showcased a Net Positive, LEED Platinum Certified four bedroom home in Lincoln, MA. This home has an impressive score of 0.27 ACH50 (Air changes per hour), which is a 90% reduction from code. ZED implemented systems such as air source heat pumps and renewables with a 13.1 kw solar PV array. She emphasized the importance of the direction the solar PV array faced, as that can hugely impact the EUI (south facing solar array is the best). It was impressive to see how closely aligned the monthly PV array predicted usage (performed by PV Watts) was with the actual usage. The homeowners are taking advantage of net metering in MA, to use the credits from the array’s overproduction in the warmer months, for the winter months when PV production is low.
In other news, the USGBC MA Chapter has a building tour of the Martin Luther King Jr. School on May 17th (register HERE), and a tour of Fort Hill on June 7th (register HERE). Come join us for our next RGBC meeting on June 12th!
The Residential Green Building Committee met on April 10th, 2017. We had a guest presentation from Dan Arons, co-founder of Architerra, speak on the challenges and obsessions related to the project cycle of green buildings. Dan has more than 25 years of experience as an architect, and he is also a founder of the USGBC Education Committee. Architerra is an architecture firm based in Boston, MA, focused on sustainable design.
Dan presented 10 key elements to focus on during a project cycle, based on his experience as an architect:
Integration from start to finish: How do the desires of the end customers, architecture firm, and all other players come together
Define boundaries loosely: You will discover new paths to reach your end goal along the way, even if they weren’t obvious from the start. Be open to changing directions mid-way through
Energy and Occupancy Modeling: Dan says the biggest challenge of green buildings, is understanding how people are going to use the building (how often and how many people)
Mock-up for Constructability: “Try it before you buy it”
Test the Mock-up: Primarily for the performance. Dan says they air test all their mock-ups
Define Building Envelope Intent: Ensure the end customer’s goals are set from the beginning
Coordinate Continuously: Communicating with all parties involved
Commission with Full Team: Always best, so everyone is on the same page on how the building will operate
Address Economics of Renewable Sources: Renewables may be the golden ticket to get a building to Net Zero
Opportunity to Act Locally or Nationally: Get involved on the local level, keep fighting the good fight
These steps are essential, as Dan emphasized the challenges with coordination and sequencing during project cycles. The committee asked some great questions after the presentation and learned some more about specific projects Dan has completed.
We continued our discussion around internal projects we are working on, and encourage more folks to join our next committee meeting to learn about what we are up to! Join us on May 8th!
The Residential Green Building Committee met on March 13th, 2017. We had a guest presentation from Jennifer Taranto, the Director of Sustainability at Structure Tone, on the WELL Building Standard (see her presentation attached).
She began by explaining who benefits from WELL, and what the standard is intended to do. WELL gauges the impact buildings have on the people surrounding/in them. Essentially, WELL benefits the people, whereas LEED benefits the environment. While some may think LEED and WELL are similar standards, there is actually about a 20% overlap between LEED and WELL, mostly related to indoor air quality.
The WELL standard is a performance-based system in which a 3rd party (Green Business Certification Inc.) verifies compliance with the requirements. After three years, WELL requires a re-certification to confirm the compliance still remains. There are three levels of certification: Silver, Gold, and Platinum (similar to LEED rankings). And in March 2017, there were 12 certified WELL projects.
Cost Structure of WELL:
Often in a business, the people (workforce) contribute to the lionshare of costs, with a smaller percentage making up the overhead costs (such as energy bills). Jennifer mentioned that investing in a standard benefiting the people of a business, yields a higher return for the business itself. To register, there is a $5,500 fee, and the cost to certify is based on a square foot price. Jennifer said that in her WELL project, there was only a 2% cost increase to use the WELL standard (1.4% came from soft costs such as an acoustical consultant).
Seven Main Concepts of WELL:
Air: HVAC optimizing, healthy materials, low VOCs (similar to the Living Building Challenge's Red List), CO monitors
Water: Filtered water, access to water for occupants
Nourishment: Access to healthy food for occupants, low sugar food, etc.
Light: Circadian lighting (blue light in morning that switches to yellow light in the evening) daylighting, and task lighting control
Fitness: Inviting outdoor spaces, prioritizing staircases, sit and stand adjustable desks, along with subsidized bike shares, yoga, and gyms.
Comfort: Thermal comfort, acoustical comfort, ADA compliance, Ergonomics (occupant-adjustable workstations)
Mind: Stakeholder engagement, wellness library (information sharing), Altruism (example, 8 billable hours to any volunteering cause)
We enjoyed having Jennifer at our meeting this month, stay tuned for upcoming presenters at the RGBC meetings! Please join us at our next committee meeting on Monday, April 10th, at 5:45!
The Residential Green Building Committee met on February 13th, 2017. Although it was a smaller meeting, Kimberly reviewed some great upcoming USGBC events, and we had some exciting policy updates.
Oren Richkin and Bill Womeldorf (members of the committee) have been doing some research around current legislative events including attending EEAC (Energy Efficiency Advisory Council), and they gave an overview of solar related news including the SREC (Solar Renewable Energy Certificate) program in MA. The DOER filed a change to the program in hopes of an extension and to keep incentives intact. The new SMART (Solar Massachusetts Renewable Energy Target) program is not expected to come online until January 2018 at the earliest (See HERE for the new tariff structure we can expect, which includes a declining block program). While we wait for SMART to kick off, the SREC II deadline has been extended to the beginning of January, 2018, but the compensation rate for the SREC will decrease from 80%, down to 70% of the SREC value. This extension gives solar customers assurance of compensation for new projects, and the SMART program will provide customers the confidence they need to predict ROI’s on any given project, and lock them in with rates from the beginning.
We have some exciting upcoming events! Join Craig Foley for Understanding the Legislative Process on March 14th. Register here. See you at the next RGBC meeting on March 13th!
