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Tag: Existing Building Performance

What Would a Passive House New York City Look Like?

New York City: the city that never sleeps—and where buildings account for approximately two-thirds of greenhouse gas emissions.

In 2019, New York City Council passed Local Law 97 (LL97) to hold building owners responsible for carbon emissions. The goal is to reduce over time, eventually reducing emissions 80% by 2050. As it stands, the law applies to most buildings over 25,000 square feet, which is roughly 50,000 residential and commercial properties across the five boroughs.

One pathway to decarbonize New York City’s buildings is using the Passive House standard: a high-performance building standard that significantly reduces whole building energy consumption by up to 60-70% while providing superior comfort and indoor air quality. When coupled with renewable energy systems, Passive House makes net zero energy buildings more feasible. (more…)

The DC Building Energy Performance Standards (BEPS) Compliance Rules Are Here. Are You Ready?

This blog post was originally published on September 11, 2019. It was updated on November 18, 2021 with new guidance in response to the DOEE’s final BEPS compliance rules. Click here to learn more.

The Clean Energy DC Omnibus Amendment Act of 2018 was signed into law in 2019, establishing minimum Building Energy Performance Standards (BEPS) for existing buildings. The law requires all private buildings over 50,000 SF to benchmark energy use and demonstrate energy performance above a median baseline beginning January 1, 2021. The law also lowers the threshold for buildings that need to benchmark; buildings between 25,000 and 49,999 SF will need to benchmark energy use beginning in 2021. Buildings between 10,000 and 24,999 square feet will need to benchmark energy use beginning in 2024.

If a building does not score above the median performance of Washington, DC buildings, it has five years to demonstrate improvement or face financial penalties. By definition, 50% of the buildings required to comply with BEPS will fall below the median—even those just a point or two under. (You can download a list of property types and their medians here.) Building owners can use this map from DOEE to check if their building meets the BEPS.

This month, DOEE released the final BEPS compliance rules. These rules cover the different compliance pathways and the documentation required for each pathway.

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DC’s Green Building Requirements for Tax Credits and Funding, Explained

The District Department of Housing and Community Development (DHCD) recently updated their Qualified Allocation Plan (QAP), which is required by the IRS for issuance of Federal Low-Income Housing Tax Credits (LIHTC), and their Request for Proposals (RFP), a companion piece that governs all other funds, both federal and local.

While there has been a large public focus on the $400 million increase in Housing Production Trust Fund announced by Mayor Bowser, another major development has been the change in green building requirements. DHCD is now requiring that all applicants for any public funding for affordable housing achieve more stringent energy efficiency targets.

New Construction (larger than 50,000 SF)

For new construction projects 50,000 square feet or larger, buildings must meet Enterprise Green Communities (EGC) Plus certification. The Plus level requires deeper levels of energy efficiency by certifying with near zero or zero energy programs such as DOE’s Zero Energy Ready Homes (ZERH), Passive House International (PHI), or Passive House institute US (PHIUS) among other programs. Currently ZERH applies to projects five-stories or less, with an expanded multifamily version expected to be released for public comment in early 2022. EGC Plus certification also requires dehumidification strategies to address potential humidity concerns.

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Choose Your Adventure: Constructing New vs. Adapting Old

Carbon emissions from new construction graphTo meet the goals of the Paris Climate Agreement, we must make decisions that will result in the greatest near-term carbon savings. This means taking into account both embodied carbon—those upfront emissions associated with the extraction, manufacture, transportation, and assembly of building materials—as well as the carbon that’s emitted over the course of the building’s operational phase.

We can build a high-performance building with very low operational emissions, but if its embodied emissions are so high that even if it’s a net-zero energy building (meaning it has net-zero operational energy consumption) it would take decades for the building to reach net-zero carbon (meaning it has net zero whole-building lifetime carbon emissions), we’re not actually helping to solve the critical issue of near-term carbon.

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Passive + Adaptive Resiliency: A Recipe for Sustainability

The need for sustainably designed buildings and infrastructure is critical as extreme weather patterns and natural disasters resulting from climate change persist. One of the truest measures of sustainability in this case is resiliency. How the site, the building, and the systems respond to an extreme weather event or other consequences of climate change can determine its livability. For green building, resiliency can be passive or adaptive, meaning reactive to these types of events or proactive in surviving them.

The recent events in Texas highlight the need at a national level for building and infrastructure resiliency.  Sudden freezing temperatures forced the grid to shut down and left millions of residents without power. The failure of uninsulated water pipes and lack of winterization throughout the energy supply could (and should) have been remediated decades ago.  In fact, a commissioned report released after similar blackouts 22 years ago recommended the incorporation of resilient designs into the system by “installing heating elements around pipes and increasing the amount of reserve power available before storms”. Michael Webber, an energy professor at the University of Texas said: “We need better insulation and weatherization at facilities and in homes.. There’s weaknesses in the system we [still] haven’t dealt with.”[1] Now, politicians and leaders are calling for more of these passive solutions that may be too little too late on such a massive scale.

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Why Commission Solar Photovoltaic (PV) Systems?

Falling costs and rising demand for clean energy have increased the specification and installation of solar photovoltaic (PV) systems worldwide. In NYC, Local Laws 92 and 94 require solar PV and/or green roofs on all new buildings and alterations where the existing roof deck is being replaced. Third-party commissioning increases the likelihood that a PV system will perform as designed throughout its lifetime and reduces poorly performing PV systems, which erode the bottom line and damage solar energy’s reputation. This is probably why the NYC Energy Conservation Code requires that renewable energy systems greater than 25 kW be commissioned (C408.2).

Many factors can affect a PV system’s power output. Let’s look at some reasons why output may be less than expected.

Design Flaws

Commissioning agents help prevent design flaws when brought onto the project early in the process. Here are a few common design flaws:

Electrical Issues: In traditional string systems, modules are wired in series to increase voltage, as shown. However, if too few or too many modules are wired in series, the voltage will be outside of an inverter’s input range and there will simply be no power output. If modules of dissimilar current are wired together output will be reduced since the current of a string is limited by the module with the lowest current.

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NYC Building Energy Letter Grades: What Property Managers Need to Know

Building energy efficiency labels are now available for property owners of large NYC buildings to download and post in their lobbies. Each year, the labels will be available on October 1st and must be posted by October 31st. Failure to display the label for applicable buildings by the October 31st deadline will result in a violation from the Department of Buildings and fine of $1,250.

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Pirelli Historic Retrofit: Part 1

 

image of Pirelli buildingOne of the most important drivers in achieving Passive House certification (or achieving any goal!) is getting the project team involved from the start. Becker + Becker, the owner, architect and developer for the creative retrofit of the Pirelli Building, hired SWA’s Passive House, LEED, Enclosures, and Accessibility teams to coordinate during early design. Becker +Becker is invested in rebuilding for resilience, sustainability, and occupant health and comfort and appreciates the necessity of getting goals defined at the outset.

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AeroBarrier: A New Tool for Gut Rehabs?

Image of AeroBarrier eventAeroBarrier is touted as the best route to never fail another blower door test. The technology, which involves pressurizing a space with a blower door fan while misting a water-based glue into the air from multiple points throughout the space, is most often being used on new multifamily buildings after drywall is installed. SWA first experimented with the technique on the Cornell Tech high-rise building. Back in March, I reached out to Yudah Schwartz at SuperSeal Insulation, Inc. about a personal project, the gut rehab of a 2,500 SF detached single family home. While renovations aren’t something they normally do, Yudah and his team agreed to try a demo. Here’s what happened.

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The Numbers Are In! NYC Passive House Performance Data

In a collaborative effort that merged financing and energy use analysis, the New York City Passive House industry finally has performance data. Working together with Bright Power, The Community Preservation Corporation, and NYC Department of Housing Preservation & Development, this analysis is the first of its kind.

Why does this matter?

Energy Use Intensity (EUI) measures energy consumption on a per square foot basis to compare buildings and allows interested parties to gauge one building’s usage to another (or to a group of buildings with a similar use type). The study team compared the actual EUI of six completed Passive House-certified and Passive House-like buildings against recently completed multifamily code-built buildings. Information was gleaned from the EnergyScoreCards database and the Passive House (PH) target. The weather normalized data indicates the Passive House and Passive House-like buildings are performing much better than the comparable code-built group, but are not quite as efficient as the Passive House threshold. Industry leaders have recognized this performance gap – between predictive assumptions that rely on standardized patterns of use and the real-life habits of actual people living in the building. This gap has been a hot topic  at the past several New York Passive House conferences. The results from the current analysis provide a starting point now, so the industry can focus on strategies to continue to reduce EUIs.

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