Posts

Interesting Elements: A Modeling view on Net Zero Homes

I recently performed some net zero energy modeling on a single-family home for work. Around the same time, I got to chatting with my neighbor (mindful of social distancing) and when I mentioned net zero,  he said, “Is that even possible?” AH! Get the word out. We have the means to offset our home energy use. What follows are the basics to consider when trying to fully offset home energy along with a break down how different upgrades can affect energy use.

There are lots of resources available on how to reduce home energy use. You can look at program requirements and guidelines like the Zero Energy Ready Program or Passive House. Through modeling I will demonstrate how the energy use numbers change and describe what we have seen in real-world examples of net zero homes. Net zero is not new and we’ll be looking at some specific pieces of single family home modeling.

Read more

The 3 Most Important Design and Construction Considerations for Senior Living Facilities

Last year, a young New Zealand lawmaker shut down a fellow member of parliament who was heckling her climate change speech with two words: “OK, Boomer.” This simple phrase started an online wildfire and ignited a conversation about the generation known as “baby boomers.” Born just after World War II, this demographic represents a period of growth, hope, and prosperity. The building, real estate, and senior housing industry has been thinking about the boomer generation for a while now. Between the years 1946 and 1964, 76 million babies were born. Every day until 2030, 10,000 of these individuals will turn 65, which means they will likely be retiring, and eventually considering how and where they want to age. This poses the question: how are we going to meet the growing demand for housing and care for this population?

image of senior couple holding hands and walking

Important Considerations for Senior Living

Whether you or someone you love is considering staying in their home as they age or moving into a senior living facility, there are a few important factors to keep in mind. SWA services for senior living revolve around the following three factors:

Read more

Choosing Insulation for Carbon Value – Why More is Not Always Better Part 2

In Part 1 of this blog post, we highlighted two of the most commonly used insulations in the U.S.– XPS board and closed-cell polyurethane spray foam – and noted that they are produced with blowing agents (HFC-based) that are putting more carbon into the air during construction than they save during building operation for many decades. We left you with a question: if we don’t use these insulations, how can we make up for the loss of the helpful qualities that has made us dependent on them?

Insulation Alternatives

One part of the answer comes from the development of new materials. In Europe over the last decade, Honeywell developed a new blowing agent, a hydro-fluoro olefin (HFO), which claims a global warming potential (GWP) of less than one, which is less than that of carbon dioxide.  First in Europe, and now in the U.S., manufacturers such as Demilec and Carlisle are coming to market with a closed-cell polyurethane spray foam that uses this blowing agent instead of the HFCs that carry a GWP of well over 1,000. These spray foams have a slightly better R-value  than their high-carbon predecessors, and otherwise have the same qualities that make them useful in multiple contexts – air/vapor barrier capability, conformance to irregularities and penetrations, etc.  However, they also have many of the same downsides – high flammability, potential (and not completely understood) off-gassing post-application, and the basic fact that they are petroleum products.

Read more

Passive House: An Alternative Compliance Path to Toronto Green Standard Tier 3

It is clear to see that the Passive House (PH) standard is here to stay! Across North America, more States, Provinces, and Municipalities are integrating PH into their building standards. One of the more recent adopters is the City of Toronto. In the most recent version of the Toronto Green Standard (TGS), the PH standard is offered as an alternative compliance path to TGS Tier 3, and with this alternative compliance path one obvious question comes to mind: What is the major difference in required component efficiency for a multifamily building in Toronto that is looking to meet either the PH standard or TGS Tier 3?

The PH standard is performance-based and is focused on decreasing whole building energy demand, improving building durability, providing optimal occupant thermal comfort, improving indoor air quality, and reducing carbon emissions. The PH standard reduces building operation costs, decreases carbon emissions, and supports an improved indoor environmental quality for building occupants. The TGS has similar goals and benefits when compared to the PH standard, and there are some obvious synergies in the program design between TGS and PH. The tiered energy category in the TGS takes a similar approach to PH by offering an annual budget for three different categories. For PH you must comply with a total energy budget for annual heating demand, annual cooling demand, and total source energy use intensity. Similarly, but slightly differently, the TGS offers a budget for total site energy use intensity (TEUI), annual heating demand or Thermal Energy Demand Intensity (TEDI), and the additional category of Greenhouse Gas Intensity (GHGI). In both standards, the path to compliance is non-prescriptive and designers can implement a variety of component efficiencies and system options. See table 1 and 2 below:

 

Table 1: International Passive House Standard energy criteria

Table 2: Toronto Green Standard Tier 3 energy criteria

 

Read more

The Making of the 2021 International Energy Conservation Code (IECC)

When I first started working at Steven Winter Associates, I didn’t know that one day I’d find myself involved in the development of codes and standards that impact how our buildings get built. I certainly don’t consider myself an expert, but I have learned a few things the hard way and thought they’d be worth sharing if you might be new to it.

So, here’s my very high-level summary of the code development process with respect to the 2021 International Energy Conservation Code (IECC), aka the “model” energy code. If you are looking for more detail, the ICC webpage has plenty of resources and a more detailed infographic than the one we’re showing and discussing here.

IECC Code Development Process Chart

Read more