What is Human Centered Design?

Post written by Chelsea Wales, SWA Intern in Washington, DC

“Human centered design is a creative approach to design solutions that are tailored to individual users. Oftentimes human centered design is about building a deep empathy with the people you’re designing for; which is critical when we design for people with disabilities.” That’s how industry experts Katie Osborn, Hansel Bauman, and A.J. Paron-Wildes define this innovative design approach. On August 2, 2016 the American Institute for Architects Committee on Accessible Design located in Washington, DC hosted its first-ever panel event entitled, “Trending Strategies for Human Centered Design”. The District Architecture Center was bustling with people of all ages, backgrounds, and abilities as they filled the glass-walled lecture room to hear the industry thought leaders discuss the importance of human centered design.

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From left to right: AJ Paron-Wildes (panelist), Victoria Lanteigne (moderator), Ben Scavone (committee co-chair), Hansel Bauman (panelist), Katie Osborn (panelist).

Moderated by SWA’s own Senior Accessibility Consultant and Accessibility Committee co-chair, Victoria Lanteigne, the panel format allowed for each human centered design professional to share their stories and expertise in their respective fields. Following the presentations, Victoria lead the panelists in a group discussion which ended with a Q&A session during which audience members asked their own questions related to human centered design. Read more

Green Homes: Consumers Follow the Money

Chris Kramer

Chris Kramer, Sustainability Consultant at SWA

By Chris Kramer, Sustainability Consultant

What Homebuyers are Looking For

A report published recently by Shelton Group has found that current and potential homeowners prioritize the value of energy efficient features over other luxurious amenities. In their annual Energy Pulse study, Shelton Group found that 85% of potential homebuyers would be willing to pay for an ENERGY STAR® Certified Home and that the ENERGY STAR appliances would be a more valuable addition to their home than a pool, state-of-the-art sound system, or home theater. These findings are illustrative of a growing trend in the homeowner demographic to seek new ways of cutting annual energy costs. With the average American household currently spending $2,150 on energy bills, upgrading old appliances and light fixtures to new ones that use less energy can go a long way in reducing this annual expenditure.
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Air-Source Heat Pumps in Cold Climates (Part III): Outdoor Units

I’ve talked a little bit about new, air-source heat pumps (ASHPs) in older posts (I, II). There are some newer products that can work really well in cold climates, but proper sizing, installation, and operation are critical for getting good performance. One key factor is proper location of outdoor units.

First, a bit of nomenclature. The part of a split air conditioner that goes outside is often called the “condensing unit.” It usually contains most of the key refrigeration components: the compressor, condenser, expansion device, etc. The only key component located inside is the evaporator coil: where the refrigerant evaporates as it removes heat from the indoor air.

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In a heat pump, all this is still true during the summer. During heating season, however, the condenser is indoors (releasing heat to the indoor air stream) and the evaporator is outdoors (removing heat from outdoor air). Because of this, calling the outdoor unit a “condensing unit” isn’t quite correct. People still use this term for a heat pump, but I think more people are simply calling it the “outdoor unit.”

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During the winter, the outdoor unit removes heat from air blowing through it. Here then, is the key point to remember:  If the outdoor unit is encased in snow and ice, it is not able to remove heat from the air. Obvious, yes? But it’s amazing how often there are lapses in this.

This image below is of a new, all-electric home, and this heat pump is the primary heating system. If this was simply an air conditioner, there’d be no problem. But this is located directly beneath the gutter-less drip edge of the roof. A lot of rain and melting snow and ice is going to fall on this heat pump. When this moisture hits the evaporator coil, it will freeze. This is a new home in Maine; I expect problems.

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Heat pumps have built-in defrost mechanisms, as some coil freezing is to be expected. However, when heat pumps are subject to extraordinary levels of moisture, the systems defrost A LOT. When doing testing for our study, we ran into this problem in several homes. The heat pump below was beneath a deck; it was protected from direct snow, but as snow on the deck melted, water dripped onto the heat pump where it froze. This heat pump only ran for 10 minutes before it needed to defrost again (run for 10 minutes, defrost for 7 minutes, run for 10 minutes, defrost for 7 minutes…). This is not good. Defrost cycles don’t generally use a tremendous amount of energy, but they usually happen only once every hour or so. If the system is in defrost mode ~41% of the time (7 of 17 minutes), it has at least 41% less capacity.

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Drip edges from roofs are pretty obvious, but the snow melt from the deck was a less obvious source of moisture. One other source of moisture that has surprised me is other heat pumps. This is obvious in hindsight, but when heat pumps defrost, there’s liquid water that usually just drips out. What happens if there’s another heat pump below? Or three heat pumps? Before some corrective measures were taken in the installation below, the bottom heat pump really had problems – cumulative ice from the three heat pumps above it defrosting.

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But this stacked, wall-mounted configuration was really efficient and convenient for this building; what to do? At this building, the owner installed piping to drain away moisture from defrost cycles (pic below). I was concerned that the ice just might freeze and block these pipes, but that hasn’t happened (and this building has been through one very cold, snowy winter).

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I think a more simple solution is a cover. The heat pump below had a simple, site built-cover. It worked fine. Observe also that the unit is on a little pad and some blocks to keep it up out of the snow.

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The blocks and pad get it ~12” above the ground. What happens if there is more than 12” of snow? Like maybe five feet? The answer is pretty straightforward: either the heat pump stops working or someone needs to do a lot of shoveling. Here they did a lot of shoveling. You may not be able to tell, but the picture above and below are of the same heat pump. Granted, this was during the record-breaking snowfall in Massachusetts two winters ago (2014-15), but there’s no sense in increasing snow shoveling loads.

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So below I think is a great solution. These heat pump outdoor units are NOT located beneath a drip edge or other moisture source, but they still have covers on them for good measure. And they’re 4-5 feet off the ground. This home is in Maine where these heat pump “hats” have become pretty common. Some heat pump distributors have contracted with sheet metal fabricators to make hats for common heat pump models.

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I think the installation shown above is great, but this may not be appropriate for all buildings. I’ve heard some stories of heat pumps mounted on wall brackets where vibrations from the heat pumps carry through the building. I’ve not seen this in any projects I’ve worked on – in my experience the outdoor units are very quiet and the vibrations are minimal – but others have certainly reported problems. This might be a bigger concern for older, 2×4 framed buildings. The home above has double 2×4 walls with exterior rigid foam – lots of vibration dampening. If vibrations from wall mounting are a concern, try to use stands to keep the outdoor units well above snow height.

The Future is Here: NYC Adopts New Energy Code

With a New York City Council vote on July 14, 2016 NYC adopted amendments to the new New York State (NYS) energy code, which go live October 3rd of this year. Since any amendments to the state code must technically be of greater stringency, there are some notable additions. In this article we NYC Cityscapewill discuss the highlights of both the new NYS and NYC energy code versions for commercial construction (includes multifamily above 3-stories) and what to expect in upcoming revisions as the bar is raised on energy efficiency and high performance buildings.

Before we discuss the highlights, here is a quick primer on the underlying basis of the new code. The new NYS energy code also known as New York State Energy Conservation Construction Code (NYSECCC) is based on a model code and standard – 2015 International Energy Conservation Code (IECC) and ASHRAE 90.1-2013. Naturally, the NYSECC is then referred to as 2015 IECC + 2016 NYS Supplement. In NYC, it’s simply 2016 NYCECC. Got it?

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The Adventures of Mo and Her No Mow Lawn

I always thought the phrase ‘about as interesting as watching grass grow’ conjured a vision of ultimate boredom. That was before I attempted to grow my own no mow lawn. It turns out that watching grass grow can be a roller-coaster of emotions: the angst of wondering whether my inability to precisely follow directions would matter… the excitement of seeing the first blades of green poking up… the anguish over bare spots… and the pride over healthy, lush sections.

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April 2015 – The lower tier is seeded; the upper tier wall-building is still in progress

For years I advised clients to consider no mow lawns in their green homes, but I had never seen the end product through a full cycle of seasons. Friends of friends who own a turf farm expressed their interest-slash-skepticism at my undertaking, which more or less echoed the sentiments of a whole stream of landscape architects before. “Sure, you could try no mow if you really WANTED to… ” A search of local nurseries turned up nothing available. I couldn’t figure out why something that sounded so ingenious wasn’t more popular! An internet search for “no mow grass” turns up Prairie Nursery in Westfield, WI as a major supplier. A colleague used their product, and they were extremely helpful on the phone, so I ordered the No Mow Lawn Seed Mix online.
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