Boston has been doing a fair job of jumping on the “green” bandwagon over the last few years and the Triple Decker Pilot Program is one of the most recent attempts to do just that. For once, this writer thinks they might be on to something down at city hall.
Clearly, the triple-decker is one of Boston’s most common architectural typologies not to mention the relative commonality of structure that could eventually allow for the streamlining and efficiencies of construction technique that would be required to create a cost-effective, sustainable program.
It just so happens that my good friend Jeremy McHugh (who also happens to be a damn good real estate attorney) and his upstairs and downstairs neighbors are participating in the program. As far as I know they are the only ones in Jamaica Plain. I am fascinated with retrofitting, repurposing, recycling and reusing as it pertains to housing in America and around the world so this project has really caught my attention. I will be following the project as they progress in a series of posts attempting to explain the benefits, introduce new technology and maybe even propose a few questions (I am a first class Devil’s Advocate and pessimist) to challenge the sustainability of the project. I welcome any and all comments and questions.
This is a pretty big story and I have had a real hard time getting started. As my father said, “you have to eat an elephant one bite at a time.” So lets start with some introductions, shall we? First, I’ll describe the program:
Get with the program
Originally the Boston Triple Decker Program was only to include two structures, but it was later expanded to five structures. It is a partnership between Nstar, National Grid, Energy Star, Historic Boston, Inc., the Boston Redevelopment Association and various builders and owners. The goal is to increase the energy efficiency of Boston’s triple-deckers and attain a HERS (Home energy rating) of 65. A home energy rating involves an analysis of a home’s construction plans and onsite testing. Based on the home’s plans, the Home Energy Rater uses an energy efficiency software package to perform an energy analysis of the home’s design. This analysis yields a projected, pre-construction HERS Index. This particular project is also utilizing infra-red optics to see cold spots and air leaks. Triple-decker owner applicants should be individuals/associations who have planned some renovation work, are willing to work with a team of building energy efficiency experts to develop their project, and are ready to proceed logistically and financially.
“Tackling energy inefficiency in Boston’s housing is one of Mayor Menino’s sustainability and economic development priorities,” said John F. Palmieri, BRA Director. “Leaky buildings cost residents more to heat and cool, and increase the City’s overall greenhouse gas emissions. In fact, the City’s climate change report found that residents and businesses could save over $2 billion in energy expenses over 10 years if we reduced our green house gas emissions by 25%.” – BRA website
Here’s the rub – building owners may be eligible for BRA and utility company rebates up to 27K per building. Keep in mind they owners will need to be prepared to put some of their own cash down on the barrel head (or finance) the balance of the work plan. Understanding the scope of work right out of the gate seems to be the real challenge here. Hopefully, as this series progresses I’ll be able to outline a bit more on how this is accomplished. The program is meant to compliment the city’s Renew Boston program and inform future Recovery Act funded energy efficiency work in Boston’s triple-decker housing stock.
Okay, now you have the gist of the program, let’s meet the players. Introducing real estate attorney extraordinaire, Jeremy Earl McHugh. His practice as described on his website:
Jeremy Earl McHugh
We provide exceptional client service to homebuyers, homeowners, lenders and others seeking legal advice and representation relating to real estate & business law.
We strive to provide legal representation that fits within your budget, because everyone deserves access to sound legal advice during those exciting and sometimes difficult times that require the guidance of a legal advocate.
Our mission is to deliver the highest quality legal services to our clients in a cost efficient and transparent manner. We utilize the latest technology to reduce paper waste and simplify the process of client communication for those who prefer to store correspondence and documents electronically. We believe that these practices are important both in terms of ecological sustainability and providing cost efficient and responsive client services.
“Earl” is also an avid biker and despite my constant protest against riding a fixed gear bike he continues to hassle me relentlessly to do so. When he’s not riding around in ridiculously colorful outfits he is participating hands-on with this project. (Confidentially, downstairs neighbor Colin said they keep him well away from the power tools.)
"Earl" the cycling contractor
Jeremy is not the only owner involved in this project however. In an unusual turn of events, three different owners bought three different units in this building, all of which were in foreclosure with different banks. If you know anything about the current foreclosure debacle – you know this was no small feat. The fact that they are now turning this old building around and creating a state-of-the-art picture of efficiency is pretty cool. I’ve only met one of the other owners who happens to live downstairs. His name is Colin Booth and he’s an architect with a firm called Sasaki in Watertown.
I had the pleasure of visiting with Colin last weekend to ask him myriad questions about the project from concept to crazy details of the technology used. He graciously answered all of my questions. Before I get into a lot of specifics about the details of the technology however let’s talk a bit more about the overall project.
Colin Booth of Sasaki Associates
Colin seems to be the ring leader of this particular project, having knowledge of the trades and a penchant for grant writing coupled with some contacts he collected from working on the MIT solar decathlon. Colin explored a number of design-related fields before finally finding architecture, which bridged his academic and activist interests. Throughout his time at the BAC he has focused on furthering his understanding of sustainable design and its impacts on process, form, team dynamics, and firm culture. Colin has been an active member of the BAC community, serving on the BAC Board of Directors for the 2007-2008 year, as well as a wide variety of student and BAC board committees, including the BAC Sustainability Council.
Sealing the Building Envelope
These 100+ year old triple-deckers are really more like swiss cheese than closed systems. Beyond insulating the structure, the contractors need to find all the air leaks (they call it thermal bypass to sound smart) and seal them up. They block off the windows and doors and install a temporary fan in the doorway.
Blowers used for detecting air leaks
An infrared device is used to scan the building repeatedly, locating the “cold” areas. Spray foam, cellulose and other materials are used to then remedy the faulty spots and equalize the leaks.
The improvements to the building envelope include air sealing in the basement and attic; addressing thermal bypass issues with pipe and wire penetrations where air was infiltrating. The open ceiling framing will be covered with loose fill cellulose which is no small feat in this case because they don’t intend to open the ceiling from within the 3rd floor unit. They will have to access it from the exterior of the building near the soffits. They’ll have to insert a pipe into the bays and get the cellulose all the way to the middle. When I spoke to the contractor he seemed unphased by this but my inner skeptic was, well skeptical. There’s a lot of stuff in your ceilings like wires and pipes, not to mention many have wooden cross supports to keep the joists from rolling over time. I think this is going to be
Cold areas highlighted by infrared camera
about as easy as getting a baby back in, but he knows best, I’m sure. The exterior was actually good news for the owners. Outstanding actually. The original estimate involved a figure of about $10,000.00 for the removal of asbestos siding.
I actually learned a very important lesson here. In the past I would have seen these (easily recognized) grooved, rectangular shingles and said they were definitely asbestos. These owners, for reasons that have escaped me, ended up testing samples with the result of learning they are not asbestos at all. Apparently there are some asbestos shingle look-like’s out there. I did some research online and found a lot of chatter about it but no way to identify the different types for sure. In any case, I’ll think twice before I condemn a project to the costs involved with removal. I’m not going to provide a link to an asbestos testing company. The only advice I have is to consider either sending the sample to a company that only tests – but doesn’t do removal, or tell them up front you only want testing and have no intention of contracting with them to do the removal. My experience comes from working with mold remediation companies. I’ve seen several mold inspections now – always the same result. Low air quality – pay us 6K to remediate the issue. I feel like it’s a conflict.
new rigid foam insulation
Once the siding was removed, the old windows are replaced with state-of-the-art gel filled windows (much more on that later), a moisture barrier (black rubber strips around windows) is applied and rigid foam insulation and strapping is applied to seal the exterior before new siding is applied. In this case the owners have chosen to reside with Hardiplank (clapboards) and after consulting my real estate sensibilities they chose a dark bluish color.
Normally, they would be able to insulate the roof wit rigid foam and cellulose from the top before applying the flat, rubber membrane – but this property had to be rescued from rampant water penetration when it was well into the foreclosure process with a new rubber roof. This makes insulating the space between the third floor ceiling and the roof a bit trickier and this is why they have to blow in insulation from the sides near the soffit.
Once the house has been sealed tighter than a Ziploc bag the issue of circulation comes in to play. Previously, air would move to and fro through the unit through the multitude of cracks and gaps pretty much everywhere. When the contractor is done with the insulation, windows and sealing process – not so much. Therefore they will have to install an ERV. Whenever possible, I let the elves at Wikipedia explain things as they usually do it much better than I.
Energy recovery ventilation (ERV)
Energy Recovery Ventilation is the energy recovery process of exchanging the energy contained in normally exhausted building or space air and using it to treat (precondition) the incoming outdoor ventilation air in residential and commercial HVAC systems. During the warmer seasons, the system pre-cools and dehumidifies while humidifying and pre-heating in the cooler seasons.The benefit of using energy recovery is the ability to meet the ASHRAE ventilation & energy standards, while improving indoor air quality and reducing total HVAC equipment capacity.
This technology, as expected, has not only demonstrated an effective means of reducing energy cost and heating and cooling loads, but has allowed for the scaling down of equipment. Additionally, this system will allow for the indoor environment to maintain a relative humidity of an appealing 40% to 50% range. This range can be maintained under essentially all conditions. The only energy penalty is the power needed for the blower to overcome the pressure drop in the system.
An energy recovery ventilator (also abbreviated ERV) is a type of air-to-air heat exchanger that not only transfers sensible heat but also latent heat. Since both temperature and moisture is transferred, ERVs can be considered total enthalpic devices. On the other hand, a heat recovery ventilator (HRV) can only transfer sensible heat. HRVs can be considered sensible only devices because they only exchange sensible heat. In other words, whereas all ERVs are HRVs, not all HRVs are ERVs, but many people use the terms HRV, AAHX (air-to-air heat exchanger), and ERV interchangeably.
Throughout the cooling season, the system works to cool and dehumidify the incoming, outside air. This is accomplished by the system simply taking the rejected heat and sending it into the exhaust airstream. Sequentially, this air cools the condenser coil at a lower temperature than if the rejected heat had not entered the exhaust airstream. During the heating seasons, the system works in reverse. Instead of discharging the heat into the exhaust airstream, the system draws heat from the exhaust airstream in order to pre-heat the incoming air. At this stage, the air passes through a primary unit and then into a space. With this type of system, it is normal, during the cooling seasons, for the exhaust air to be cooler than the ventilation air and, during the heating seasons, warmer than the ventilation air. It is this reason the system works very efficiently and effectively. The Coefficient of Performance (COP) will increase as the conditions become more extreme (i.e., more hot and humid for cooling and colder for heating).
The efficiency of an ERV system is the ratio of energy transferred between the two air streams compared with the total energy transported through the heat exchanger.
With the variety of products on the market, efficiency is unquestionably going to vary from product to product. Some of these systems have been known to have heat exchange efficiencies as high as 70-80% while others have as low as 50%. Even though this lower figure is preferable to the basic HVAC system, it is not up to par with the rest of its class. Studies are being done to increase the heat transfer efficiency to 90%.
The use of modern low-cost gas-phase heat exchanger technology will allow for significant improvements in efficiency. The use of high conductivity porous material is believed to produce an exchange effectiveness in excess of 90%. By exceeding a 90% effective rate, an improvement of up to 5 factors in energy loss can be seen.
The Home Ventilation Institute (HVI) has developed a standard test for any and all units manufactured within the United States. Regardless, not all have been tested. It is imperative to investigate efficiency claims, comparing data produced by HVI as well as that produced by the manufacturer. (Note: all unites sold in Canada are placed through the R-2000 program, a standard test synonymous to the HVI test).
To be continued…
Next I’ll discuss the HVAC and tankless hot water systems that will be employed and it WILL BE SCINTILLATING!