Winter Passive Performance

Earlier this week the project team began a seasonal experiment to test the passive performance of the envelope to resist exterior temperatures fluctuations over the course of 72 hours (3 days). To complete this study, the heating and cooling systems are completely disabled for the duration of the period (though the ERV remains in operation to supply code required minimum ventilation).

Earlier forms of this same test have shown interesting returns, generally showing the envelope is able to maintain a steady temperature range. Observations from June remained outside of the comfort zone entirely, however, though night temperatures clearly dropped into the comfort range. Effort by the resident to purge warm interior air in the evenings could have altered this, though high humidities in the Southeast-US often negates such efforts.

We'll keep you posted as to what we find this time around!

Hello snow!

A winter storm swept across much of the southeast today leaving a blanket of snow on the New Norris House. Here are a few photos from this beautiful, snowy afternoon:

Wooden side door looking warm and welcoming

 

Aluminum bed-edging making its mark

Sunset colors

Stone path to the woods

Rainbow chard in the raised beds

Pump and watering can at rest for winter

Stay warm out there!

Presentation at TN ASLA Conference

Last week, the New Norris House made an appearance at the TN Chapter of the American Society of Landscape Architects Annual Conference in Nashville, TN. The presentation was geared toward landscape architects, and focused on our landscape design and water harvesting and treatment systems.

We began with an overview of the original town plan, including the greenbelt that protects the community's watershed and the network of walking paths that link individual homes to the town center.

We then looked at the original Norris cottages and landscapes and discussed how we could re-interpret the efficient, technologically advanced homes and the productive, functional landscapes of the original Norris plan into 21st Century standards.

  

I showed the planting plan, and how we reflected the towns water-guarding greenbelt with our own site-scale native grass meadow, which is designed to capture and infiltrate storm water sheet flow.

 

We then looked at the locations and functions of our integrated rainwater harvesting and treatment and greywater treatment systems.

Now that we have a year's worth of data on the water systems, I explained what we are learning. Our data shows that we have been able to reuse about 1,990 gallons of greywater for landscape irrigation per month. Over the course of the previous year, we were able to infiltrate almost 24,000 gallons of greywater into the groundwater table, keeping that water out of a waste-water treatment facility. We are also monitoring the infiltration rates of our greywater. In the graph below the red, green, and dark blue lines represent data from pressure sensors located in the greywater bed. The spikes show an increase in atmospheric pressure, which indicates water entering the bed. Each spike represents an influx of water into the bed, so we are most likely seeing showers and loads of laundry here.

We also looked at data on the rainwater quality and quantity. Our monthly pre- and post-treatment rainwater samples are showing that our treatment system is able to produce water that is safe for human contact per EPA human health criteria.

In terms of rain water quantity, we have been able to provide over 800 gallons of treated rain water for use on the home each month. That's almost 10,000 gallons a year! However, due to the size of our cistern and weather and use patterns, we are only using about 40% of the rain water that falls on our roof in the home. The other 60% (about 15,000 gallons) is used for vegetable garden irrigation or is infiltrated into our terraced rain gardens.

With our low-flow water fixtures and rainwater supply, we have been able to reduce the New Norris House potable water consumption by 68.5%. If all of the approximately 700 homes in Norris were able to reduce their municipal water demand by New Norris House standards, we could save over 25million gallons of water a year. That's 34 Olympic-sized pools!

One question asked after the presentation was what I thought was the biggest lesson learned from our data analysis. I think that what we are learning about the successful infiltration in the greywater bed is most interesting. Due to our clay soils and location on a slope, I am very pleased to see how well this bed is performing. Also, the greywater bed is one of the least expensive landscape features we designed, so it could be easily reproduced on other properties. Way to go, greywater bed!

DIY Network features the New Norris House!

The New Norris House is featured on the DIY Network as part of a series on space-saving, sustainable design! Check it out!

Photo credit: Jason Kisner / diynetwork.com

Residency Year Two

It's hard to believe but August 2012 marked our one year anniversary of occupancy at the New Norris House! The upcoming year of residency and evaluation has just begun, and I'm excited to serve as the 2012-2013 resident. My name is Valerie Friedmann, and I have been part of the New Norris House team since the spring of 2010. I am a graduate of the University of Tennessee Graduate Landscape Architecture Program, and I am now teaching design studio in the UTK MLA program. My role at the New Norris House has mainly been in the design and implementation of the home's landscape and integrated water harvesting/reuse systems. During the evaluation phase, my role is to oversee the monitoring and evaluation of the water systems, monitor and maintain the landscape, and of course, blog about it!

Hey, that's me collecting some water to take to the lab!

For my first post as the new resident, I wanted to write about what I'm enjoying most since moving in. To me, seeing the native grass and perennial meadow take shape over the past few weeks has been astounding. Late summer is always beautiful in East TN, as the fields and roadsides turn golden and red and purple. Our design intent at the NNH was to bring the charm of a field left to meadow into our residential landscape. Aside from beautiful early fall color and texture, our meadow provides habitat and sops up stormwater runoff.

Broomsedge and Rudbeckia blooms

The late summer texture and color of Little Bluestem (Schizachyrium scoparium) complement the colors of the home

As the meadow grows, the plinth is starting to feel like an outdoor "room"

Swale in May, just after plugging with grasses...

...and after 4 months

For more info on the techniques used to establish our native grass and perennial meadow see the previous post Meadow Planting Day and landscape photos.

On September 13 we gave a presentation of our first-year's data analysis to the City of Norris Recycling Commission. Look for next week's post for details on how much energy and water we saved last year!

Reflections

It’s hard to believe that our year of living in the New Norris House is over. During our time there, it was a bit like living in a lab; our energy and water usage were monitored, and we tested the design and systems installed in the house. Although we’ve moved out, there are several things we grew to appreciate while living there that will stay with us.

Natural light 
We loved the natural light that filled the house during daylight hours. The roller shades over all the windows block direct sunlight and help keep the house cool, but don’t block the light entirely like blinds or curtains would. Even on cloudy days, the skylight in the living area let in enough light so we didn’t need to turn on the kitchen or loft lights until dusk. The skylight and kitchen window are two features in the house I miss the most.

the windows, skylight, french doors all let in plenty of light (source)

Design
Initially, we weren’t sure how scaling down to 768 square feet would work—would we be able to fit our things in the house, and would it feel too small? We discovered that although the footprint of a living space may be smaller, it can be more functional than a larger space because of its design. The house’s layout provided small private areas (bedroom and bathroom) with a large open living space where most of our time was spent (the kitchen and swing space). The house has ample storage, with cabinets in all rooms and bookshelves in the swing space and loft. While the loft space didn’t make the footprint of the house seem larger, it provided a separate area for relaxation.

a small footprint of great design (source)

Rainwater use
The rainwater cistern and filtration/purification system was explained to us when we first moved in; rainwater is collected from the roof into a cistern, then purified and used in the house for washing clothes and filling the toilet tank. I was a bit skeptical about how well the purified rainwater would work in the washer, but it did the job just as well as fresh water. The washer water had a leaf-like smell to it, but was noticeable only when opening the washer door to transfer items to the dryer. After being in the house for a few months, I found myself looking forward to rain, knowing it would keep the cistern full and provide water inside. Before living in the house, I hadn’t given any thought to repurposing rainwater; the firsthand experience of being able to reuse water has made me more mindful about how much fresh water I use daily.

rainwater on the back porch railing (source)

After moving into the house, we were asked if we thought our quality of life would be affected by living in a smaller and energy efficient space. Living in the house affected us positively, with design and systems we wouldn’t have experienced otherwise. Much like the original residents of Norris who were introduced to electricity in their homes 75 years ago, we had the opportunity to experience the latest in energy efficient and sustainable systems, in the same community where electricity came to Tennessee. While the house looks a bit different than the first Norris cottages and the use of electricity has expanded to support computers and telecommuting, the experience we had there was educational, helping inform us about design and energy choices we can make wherever we might live in the future.

Greywater Monitoring Update

As part of our water system evaluation, monitoring efforts have recently been expanded to include a greywater (water from the bathroom sink, shower, and clothes washer) component. Here we will not be monitoring quality (as we are with rainwater), but rather soil saturation of the greywater bed. To state regulators, this is a primary concern. Discharged greywater must stay below the surface level, and this is what we seek to gain further insight about.

The greywater beds function by layering gravel, mulch, and soil around a perforated 5-gallon reservoir (bucket). As greywater enters the bucket, it is allowed to slowly saturate the sourounding bed. We have designed the bed to hold over 150 gallons of greywater.

Greywater bed (top, in green) accepts all greywater from the home. A section through the bed itself (below) provides details about how the bed is built up from the subsoil.

What we are interested to learn is how quickly the bed saturates and how quickly it will drain into the subsoil. 

This is where our friends in Biosystems Engineering and Soil Science come in. Working with Dr. John Buchanan we have recently installed a sophisticated monitoring system and have begun analysis of the data. The monitoring system consists of two components: 

1. Piezometers: Slotted PVC pipe cored 2' into the beds and surrounded with filter sand. Inside of the piezometer is a pressure sensor, which will tell us the water level as it moves up and down within the bed. 

2. A new datalogger: The system is wired to a datalogger that automatically logs water levels within the bed every 2 minutes. 

Initial Analysis:

As you can see from the graph below, the water level within the beds fluctuates quite a bit between the 3 testing locations. 

NOTES

-The values to the left indicate water level. Currently, the graph is displaying an electrical signal being output by the pressure transducer. This still needs to be analyzed and interepted to determine actual water level.

-To that same effect, each port needs to be adjusted for the physical elevation of each installed pressure transducer. They are at roughly equal levels, but this will certainly affect the numbers we receive. 

-Port #1 (dark blue line) see hardly any greywater at all (as it is on the upslope of the bed). 

-Port #3 (green line) shows a water level increase directly correlated to input (bucket- red line), but the space between the two lines clearly shows there is more saturation potential.

-Rainfall (light blue) indicates a possible relationship to the saturation within the bed, but not as much as initially suspected. This will need more data (and more consistent weather). 

More to come soon! Thanks for reading!