Ann Wilde

If you’ve ever planted a garden, or even one pumpkin seed, you know the excitement of seeing those first sprouts emerge. So imagine thousands of plants and flowers surfacing, expertly orchestrated to grow and bloom spring through fall to bring function and beauty to the Green & Main site. The Green & Main Pilot Project landscaping was installed this past October, so you can count on a burst of fresh greenery and flowers to greet spring.

Beginning the Installation Process

Just in the nick of time, the Green & Main site was ready for the grass and flower plugs to be installed. Under the design guidance of Zach Heitzman of Green Bean Landscapes in Ankeny, the task of strategically positioning the plants to support the site’s environmental and aesthetic goals began.

Blue Lobelia

I talked to Zach on a chilly December day as he worked in his Ankeny office designing Green Bean’s landscaping projects for next spring.

“Really, the basic concept of the Green & Main’s landscaping had been sketched out for a long, long time by the Green & Main team” stated Zach. “My role was to incorporate landscaping into the site that would accommodate their stormwater management goals, including building a bioswale, meeting the LEED and SITES (the Sustainable Sites Initiative) requirements, and offering an aesthetically pleasing experience as well. It was all about creating the details around the vision.”

“Of course, the final design also had to be documented for the City of Des Moines’ approval to ensure it complied with their guidelines regarding ground elevation, easements and pavements,” concluded Zach.

Butterfly Milkweed

Contaminated Soil Amended to Make Ready for Our Plants

Before a single seed was planted, the soil at the site needed to be amended.

“Since the ground had been used for many, many purposes over a hundred or so years,” Zach noted, “we assumed that it would be contaminated with impurities. So the first step was to amend the soil. As required by SITES, we documented the before-and-after health of the soil. Prior to amending it, we took samples of the existing soil and sent it to the USDA where they evaluate the nutrients, the permeability and the organic matter. Then we sent a sample of the amended soil. We also sent samples to Iowa State to test the organic matter. Before-and-after test results have yet to come back.”

The method used by Zach for amending the soil was one that was recommended by the Iowa Department of Agriculture and Land Stewardship. This method included using a mini excavator to tear up 24 inches of the site’s topsoil to make it less compacted. Prior to this, two inches of compost were placed on top of the ground in order to be incorporated into the existing soil. The affect is a significant increase of organic matter and nutrients in the soil. Also, by making the soil more permeable and nutrient-rich, we now have soil that absorbs stormwater much more aggressively.

The compost used on the Green & Main site was acquired from Des Moines Metro Waste Authority and consists of leaves, sticks, and grass clippings that were collected from Des Moines residents and businesses.

Prairie Aster

How SITES and LEED Requirements Affect the Landscaping Design

SITES and LEEDs requirements apply to the Green & Main landscaping design primarily in the areas of increased energy efficiency, water conservation and stormwater management.

Energy efficiency.

Zach designed the strategic placement of shade trees in the landscaping in order to decrease the heat inside the building. According to the EPA, trees and vegetation lower surface and air temperatures by providing shade as well as through evapotranspiration, the process of transporting water into the atmosphere. Shaded surfaces, for example, may be 20–45°F cooler than the peak temperatures of unshaded materials, which then decreases demand for air conditioning.

Water conservation.

Using plants that are more adaptive to our climate will thrive without a lot of extra fertilizing and watering. Once these types of plants are well established, they are pretty self-sufficient.

Stormwater management.

The type of vegetation incorporated in the Green & Main landscaping was selected specifically for its ability to absorb more water via root systems and soil. Vegetation reduces runoff and improves water quality by absorbing and filtering rainwater.

Prairie Blazingstar

A small bioswale was also built by Zach Heitzman to affect stormwater management goals. “This was one of my more challenging projects at the Green & Main site,” added Zach. “Essentially I had to create the bioswale by hand. It was too hard to bring in machinery to dig and form the bioswale, so I came in with a rake, shovel and wheelbarrow. More challenging was keeping the construction crew away from it! Of course, there were a lot of people on site and once we graded and shaped the bioswale, we couldn’t have people walking over it.”

“Overall, I’d say that the vegetation on the site is more functional than aesthetic,” concludes Zach. “[But] it will definitely be beautiful, from spring through the fall.”

Kelly Hayes of Allendan Seed…and Her Forbs

Allendan Seed of Winterset is one of the largest producers of native prairie grass and wildflower seeds in the United States. Allendan Seed produces over 250 species of native grass and wildflowers. Dan and Sonia Allen began farming conventional row crops in 1976. Today they are still a family operation. Their four children migrated home to farm upon graduating from Iowa State University.

Prairie Dropseed

Daughter Kelly Allen Hayes is Allandan’s production manager. She oversees the greenhouses and fields, planting about two million seeds a year, overseeing all production from plugs to harvest on the company’s 40 acres.

“Forbs” are technically defined as herbaceous flowering plants, wildflowers being a type of forb. Kelly Hayes can assure us thousands of these little beauties will poke up through the ground at the Green & Main site come next spring.

“Once I had become familiar with the Green & Main site itself and the objectives of the initiative, I chose over 30 species of plants, grasses and forbs to incorporate into the landscaping,” said Kelly. “I focused on species with root systems that would be beneficial to the ecosystem, aiding with stormwater absorption and water conservation. But I also added some visually appealing colors, heights and textures to the site that will appear from spring to fall.”

Some of the species planted by Kelly are prairie violets, prairie smoke, prairie blazingstar, prairie dropseed, little bluestem, blue lobelia, rattlesnake master, New England aster and silky aster. Butterfly milkweed was placed all along the bioswale. The plants and flowers range from four-inches to seven-feet tall. “I also incorporated some mountain mint into the landscape,” continued Kelly. “Mountain mint really aids in erosion control because it forms runners, essentially a type of living carpet after a few years of growth.”

Prairie Smoke

Personal Touches to the Landscaping

The designer’s creativity plays a part in any landscaping project, and Zach Heitzman’s creative contribution to the site can be found in every foot of the landscaping. However, in talking with him, he says his most significant personal contribution to the design is in the limestone incorporated into the landscaping.

“One of my favorite parts of operating my own business is that I can create my own designs in some of the detailed elements,” explained Zach. “The limestone pieces that I worked with were acquired from an Anamosa quarry – all limestone in Iowa comes from the Anamosa area – and they are a rich cream color that really complements the site. The pieces of limestone are raw and broken, so I created natural-looking outcroppings among the plants and placed some of the stone in an informal path that suggests native limestone outcroppings.

Prairie Violet

“I’m proud of that stonework on the site,” continued Zach. “But I’m mostly proud of how we all worked together to make the final landscaping a success. We got it done to specifications within a very tight timeframe. Everyone really contributed their talents to the project and that collaboration resulted in success”

Asked what he would do differently if he had more space to work with, Zach responded that he’d love to have the additional space to incorporate more educational opportunities. “I would really like for people to be able to walk through guided pathways with signage explaining the plant species and how they specifically benefit the environment.  I would use the very same technologies that I used on the Green & Main site; I’d just make it a more dramatic experience for visitors.”

A big “thank you” to both Zach and Kelly for the colorful flowers and vegetation coming up next spring. I, for one, am looking forward to it.

–Ann Wilde is a Des Moines marketing strategist and writer who also has a special interest in preserving and creating sustainable communities.

Chaden Halfhill on the first floor during construction.

On Site in December

Frost has settled into the soil at the Green & Main pilot project and layered clothing has become the norm on site. Cold weather slows everything when it arrives, even our perceptions of time. Transitioning from fall, our project processes shift and schedules expand as the conventions of construction industry adjust to the freezing temperatures that turn work trucks into rolling coolers.

The impact is seen in so many ways: battery operated tools are removed daily, liquids no longer remain in vehicles over night and time is regularly allocated to warm up engines and scrape windows. Little can be taken for granted. The brunt of winter is felt from head to toe when the winds blow from the northwest, and the subtle influence of sunshine, wind breaks and overnight lows are reflected in ever-changing schedules and routines, especially for those projects or tasks that remain on the exterior of the building. At least measurable snow has been minimal thus far, allowing us ample access to staging areas, which has proved helpful.

I-Jobs sign that shows that program's contribution to our project.

Grant Completion and Year End Wrap-Up

The inevitable approach of the calendar’s fiscal end and year-end business planning creates another transition that limits production as administrative attention is directed towards financial matters. This annual responsibility was more intense this year due to the push to complete the landscape, allowing Indigo Dawn to complete major work on grant-supported tasks.

Paired with this completion of tasks, compliance and reporting requirements stretched staff to compile and aggregate data that highlights our applied best practices, educational efforts and communications, as well as financial budgeting and allocation of funds. Our compliance and communication team fulfilled all these obligations and provided data to initiatives and agencies that promote water conservation and stewardship. The benefit of all this hard work will be evident in the spring, as the native plants return from their dormancy and sprouts pepper the amended soils with aspiration.

Sustainable SITES landscaping initiative, the first in Iowa.

As internal efforts at Indigo Dawn focused on closing out grant responsibilities for site development, attention on site was narrowed in order to wrap up the exterior enclosure for the addition. We worked to protect the building from winter weather and prepare staff to switch focus, redirecting the scope from exterior work and stormwater management practices to heightened attention on energy efficiency efforts. In particular, interior efforts will focus on the installation of the utility systems and integrating myriad details that support the insulation’s installation and building’s wall assemblies.

Construction and Masonry

Aside from finalizing the building enclosure, the general contractor, Silent Rivers, also assisted with the city’s replacement of the 19^th Street sewer, which had collapsed and was discovered by the team in early spring when Pary Plumbing Corporation attempted to connect a new sewer drain from the city sewer to the building. The building was without sewer service for nearly nine months and everyone associated with this project shared an eagerness to tie back into the municipal system, providing drainage capacity within the building for all tradesmen working on its restoration.

Masonry work on the addition.

Within the plastic and scaffolding enclosures that have encapsulated the addition’s sheer walls for the past 4 weeks, masons from Atlas Masonry quietly installed the exterior 6” veneer cladding that protects the 2” Dow extruded polystyrene insulation that wraps the addition.

What appears to be a simple masonry cladding system has many critical details that support the long-term performance of the addition.  Masonry is a reservoir cladding, and as a result, precautions are taken to ensure moisture behind and within the block or behind the veneer is properly managed through the use of flashing and wick ropes. These practices and their proper application allow moisture to exit the wall assembly, protecting the interior structure.

Because protecting against bulk water intrusion is first priority for any wall system, much attention has been paid to details throughout the addition, setting tone for the various strategies to insulate and manage moisture within the existing building’s retrofit. From protecting the foundation from ground water to managing water intrusion during summer rains, there have been so many decisions that have required thoughtful consideration and a vast amount of discussion to reach each solution.

A rendering of the completed building, facing north.

With the masonry walls recently completed, final installation of siding on the western face of the addition has begun. Starting from the insulation plane, we have applied several layers to the wall systems, starting with the water barrier membrane and integrating flashing details for the first group of Pella triple pane windows scheduled. Three quarter inch treated battens have been attached on top of the membrane, preparing the wall for a rain screen made of James Hardie cement lap siding, thus providing an effective drainage plane for the wall system. Two scuppers will be installed through this wall in order to shed water from the lower roof. Resolution of these understated water conduits will allow for the completion of the upcoming roof by Academy Roofing and provide weather security for the new addition, in the event we get a deep snow.

Fortunately, this week’s forecast remains 1 inch or less.

–Chaden Halfhill is an entrepreneur and visionary of the Green & Main Initiative.

Extensive Collaboration

The installation of the H2OG, one of the 7 stormwater management practices.

During October, focus intensified on the completion of seven stormwater management practices that are incorporated within the project’s site plan and ecological restoration strategies. Deadlines and the onset of seasonal changes intensified the pace of our efforts significantly. Fortunately, daily temperatures hovered above average and very few work days were interrupted by rain.

Collaboration, along with bright blue skies, was in abundance. The tradesmen skillfully orchestrated their varied and intertwined tasks, culminating in a buildup of native plantings and graded soils that reinforced the beauty and meaning contained within Green & Main.

Native plant groundcover placed on site.

Site Transformation

If one stands on a pile of salvaged wood that is staged on 19^th Street Place, the undeveloped dirt road bordering the west edge of the property, and surveys the site, transformation is evident. From this vantage, the whole site unifies; the natural landscaping frames the project’s architectural evolution, highlighting its history while celebrating its renewal within this historic neighborhood.

The stormwater management methods we’ve installed connect the building with the site, bridging this localized urban context to the larger Des Moines community, and then on to join nationwide water conservation efforts.

Landscaping on the south and west of the property.

Blending so many practices in such a small area (less than one acre) is a unique achievement. The stormwater management systems that we carefully planned and integrated include the vegetative roof, rain water collection, soil quality restoration, bio-swale, bio-retention through site grading, native landscaping and a pervious paver system.

The overarching goal of the design and engineering of all the practices was to demonstrate effectively the fluid connection between building science and urban landscaping. We wanted to show the varied choices building and home owners have in managing the movement and absorption of stormwater on a smaller plot of land.

Starting from the northeast side of the property, the path of rainwater may be followed visually as it connects the property’s higher elevations to the rain garden at the southwest base of the site, where it will be absorbed or discharged downstream into the city of Des Moines’ right-of-way.

Sedum installed on the vegetative roof.

The path of the water’s movement maps out different lessons for visitors to experience. For example, rainfall may begin its movement from the vegetated sedum roof on both the main building and the addition. From there, it moves into the guttering system that supports the solar array and on to the salvaged brick gabion baskets. Here, it continues through the richly amended bio-swale and down to the rain garden filled with native plants where it pools and infiltrates. The rainwater from the permeable parking lot also gathers here, along with overflow from the rain harvesting system that is visible at the rear of the paver lot.

Many Trades Involved

What remains perhaps less obvious behind this view is the combined effort of so many tradesmen weaving together material, talent and time. We believe the passion for their craft and their dedication to the stewardship of this project is profound, and the matured presence of the landscape will inspire generations of people who visit to learn about conservation and sustainable building practices.

Newly added permeable paver parking lot.

Masons, cement finishers, carpenters, laborers, machine operators, excavators, landscapers, growers, roofers, pipe-fitters and electricians all worked together as we reclaimed this raw urban site peppered with sub-surface remnants of its historic past. From century-old foundation bricks to an array of early 20^th century glass bottles, we unearthed and removed truckloads of debris, reusing or recycling everything we could. Even four thousand pounds of cast iron boiler buried next to a brick kiln was hoisted from ten feet below grade.

Glass bottles unearthed while working with the geothermal system.

Much like establishing a solid foundation before working on a building, the restoration of this site required significant structural changes to not only comply with zoning requirements but to help remove years of impact. Many disciplines were layered together in order to generate our results. For example, the geo-thermal well field is connected below the permeable parking area and required attentive installation and metering, as measuring its performance outcomes in the future are integral to two research projects.

On the southern perimeter of the property, a team of bridge-builders, led by an eighty-year-old foreman, built the concrete retaining wall that borders the sidewalk. This construction inaugurated the site reclamation process while also providing the opportunity to bring in utility services below grade and to integrate the perimeter drain for the building into the site design.

The construction of the southwest retaining wall by Jensen Construction.

High Levels of Commitment

Completing so many layers, sometimes simultaneously, on time to meet our autumn deadlines required a personal commitment by many people to work together on a single dedicated vision – sharing a professional collaboration worth recognizing. I am honored!

With the weather now turned, and temperatures dipping below freezing, we are stretching both funds and time to enclose the building envelope and draw our attention inward for the winter. Inside the building, we will begin to install the engineered systems that support the building and its habitation in our complex northern climate zone. We now turn our focus to weatherizing the building to prepare for further work: optimizing the efficiency and performance of the building itself and scaling the developmental terrain of the Green & Main Pilot Project.

–Chaden Halfhill is an entrepreneur and visionary of the Green & Main Initiative.

Soil staging on site.

When embarking on any building or renovation project, managing soils and the handling of erosion control may be one of the first thoughts to occur. This consideration is crucial, really, to the healthy development of sustainable neighborhoods and to the networks of interconnected systems. Throughout much of the early 1900’s, farming practices sometimes did not think to address erosion specifically and consequentially farmlands lost half an inch per decade of topsoil each year. Not only is this loss of topsoil detrimental to the productivity of our farmlands but the material that runs off the land clogs waterways and disrupts aquatic life.

The LEED and Sustainable SITES programs provide extra focus on erosion control and other soil management methods. This focus makes soil conservation one of the first points of concern, so that when any ground vegetation is disturbed, appropriate restoration methods are designed and implemented as part of the original planning.

At Green & Main, we would like to preserve the ground cover to prevent the exposure of new soil as much as possible, as relevant plant life is the best erosion and stormwater control method. Typically, when a construction project is underway, silt fencing and cloth/straw socks are used to prevent water from carrying away soils. On site, we also focus on vehicle entry ways, using gravel and similar materials to prevent soils from being carried into the streets by vehicle tires.

Bio-retention grading and bio-swale.

When planning for superior erosion control, it is important to look beyond initial construction. Natural barriers such as swales and rain gardens help inhibit erosion and promote deep groundwater infiltration. Careful selection of plants also helps hold soils and slow the movement of water through the site. The soil composition itself can assist with water retention and water control. In fact, adding compost to the soil helps absorb the water and an addition of two inches of compost can hold up to five inches of water.

Taking the lead, Green & Main has incorporated many methods of soil and water management to contain water onsite, particularly by means of creative water pathways, bio-swales and rain gardens. This project has rebuilt and revitalized the original soil and transformed a typical urban grass yard that has seen much change through the years into a native plant habitat. Going well beyond the standard measures of erosion and water control, Green & Main has rebuilt a local soil ecosystem using this organic approach to green building and soil management.

– James McCain is a renewable energy expert and a future organic farmer. He played a recent role in the establishment of the Tallgrass Grocery Co-Op in West Des Moines.

LEED (Leadership in Energy and Environmental Design) is a multi-tiered voluntary rating system for the construction, renovation and/or rehabilitation of buildings. Administered by the USGBC (United States Green Building Council), LEED classification reflects the spectrum of the environmental performance of a building. The Council is comprised of engineers, architects, designers and building officials, who, through committee and in adherence to USGBC policy and procedure, develop and guide the rating systems.

As LEED for New Construction Rating System states, “(b)uildings fundamentally impact people’s lives and the health of the planet. In the United States, buildings use one-third of our total energy, two-thirds of our electricity, one-eighth of our water, and transforms land that provides valuable ecological resources.”

From the inception of the Green & Main project, developer Chaden Halfhill, committed himself to renovating the mixed-use building in the Sherman Hill neighborhood in accordance with the LEED rating system, aspiring to reach the highest certification – platinum.

There are four levels of certification, certified, silver, gold and platinum and five separate categories in which this may be achieved:

• Green Building Design & Construction
• Green Interior Design & Construction
• Green Building Operations & Maintenance
• Green Building Neighborhood Development
• Green Home Design & Construction

There are a total of 100 points possible within the current version of LEED, with the following breakdown:

• Certified – 40 to 49 points
• Silver – 50 to 59 points
• Gold – 60 to 79 points
• Platinum – 80 points and above

Illustration of Green & Main upon construction completion.

The Green & Main Pilot Project is implementing the first category, Green Building Design & Construction, with many of the ratings cross-pollinating to most or all categories. The ratings, or credits, that are assessed boil down to a few key elements: water use, energy use, construction and materials waste, materials used, indoor building quality and the site itself.

Below is a project checklist for some of these areas. They are judged by efficient use of resources and the extent to which the credit contributes to or improves health, comfort, accessibility and the environment.

• Construction activity pollution prevention
• Development density and community connectivity
• Heat Island Effect
• Alternative transportation accessibility
• Stormwater design
• Water efficient landscaping
• Innovative wastewater technologies
• Water use reduction
• On-site renewable energy
• Optimizing energy performance
• Enhanced Refrigerant Management
• Storage and collection of recyclables
• Construction waste management
• Building reuse
• Materials reuse
• Regional materials
• Outdoor air delivery monitoring
• Indoor chemical and pollutant source control
• Increased ventilation
• Low-emitting materials
• Thermal comfort
• Innovation in design

How Green & Main is Guided by the LEED Checklist

The use and implementation of water, as one of our precious resources, is central to the LEED credit system. LEED gives points to projects that harness rainwater, reuse grey water and reduce general water usage. The way we, and our buildings, use water plays a critical role in any system that addresses long-term sustainability.

Green & Main’s newly installed vegetative roof.

The Green & Main project has created many ways to manage stormwater, water use and to promote water reuse. Much thought about design and building engineering was put into the creation of the vegetative roof. This green roof collects and stores stormwater, thus reducing the amount of water that travels through the city’s stormwater and sewer system. This reduces the impact on our urban storm sewer infrastructure.

The vegetative roof and its drainage also serve to guide excess water to the ground, then to a bio-swale which will move water to a rain garden where it will infiltrate. The bio-swale and rain garden are also instrumental in storing, cleaning and infiltrating excess waters from the permeable parking area for the building. Native plantings provide a wonderful aesthetic while enhancing the site’s capacity to manage water. An H2OG Rainwater Harvesting System was installed on a concrete wall constructed in the transitional space between the parking area and the overall landscaping, adding a significant reservoir of naturally occurring water on site.

The energy component of the LEED credits analyzes each project based on how it is able to reduce energy usage through a variety of means: energy efficiency measures, efficient cooling and heating systems and the ability to generate renewable energy on site. The goal for a building is to strive for Net Zero in total energy consumption versus production, or even to be a net energy producer. Many of these goals reinforce strategies and suggestions promoted by the initiative Architecture 2030. The closer a project is to meeting this goal, the more LEED points in this area it will receive.

Pallet of bricks placed to the side of the building.

The management of material use streams and the waste generated is also a major component in protecting sustainability, including the relationship between refuse disposal and land management. How a project deals with construction materials and debris will dictate how many points it will receive. Each piece of garbage and waste has embodied energy and value. Society’s practice is to bury practically everything in landfills. Projects that attempt to get points in this category are helping to develop recycling markets that otherwise would not exist.

In a March 1, 2011 article, Steve Wilke-Shapiro discussed intentional deconstruction as a way to express the integration of sustainable building practices and environmental considerations. “This term,” Wilke-Shapiro writes, “differentiates our work from traditional ‘demolition,’ where little care is paid to either the remaining structure or what happens to the materials once they are removed. In contrast, intentional deconstruction looks at the project holistically: existing materials removed as part of the renovation are carefully removed with the intention that they be reused in other applications or recycled when possible.”

Our project incorporates recycled flooring, reused wood for framing and repurposed materials, which are central to its sustainable construction philosophy. Ann Wilde, in her May 31, 2011 article “Green & Main Shows off ‘New’ Maple Flooring… and Gives Salvaged Gym Floor a New Home,” details the salvaging and reuse of flooring that was in the gym of the former Cambria, Iowa school in southern Wayne County.

Inserting the repurposed maple flooring.

Projects may also gain points in careful use of materials. Wise and efficient reuse and restoration supports energy-saving building techniques and LEED allows for multiple pathways in which a project can attain these credits. Adaptive reuse of a building in a blighted urban neighborhood will earn far more points than a new construction project in the suburbs for this ratings area. New materials used are considered in the point system, and new items created from recycled or efficiently-produced components help build point consideration. Such materials include salvaged and reclaimed materials, green products, certified wood and local materials.

The LEED process promotes a keen understanding of a building’s indoor environmental quality as well, through encouraging control of lighting systems (passive and electrical), thermal systems (including HVAC, insulation, window and building envelope integrity), ventilation and the management or prevention of indoor chemicals and pollutants (the absence of volatile organic compounds).

The Built Environment

It is critical to consider the intricate interplay between the constructed human environment and land use. Where is a site located and how is it connected to the larger community? Is it a natural landscape or is it a dilapidated building in the midst of an urban environment? How is stormwater managed? How is erosion prevented? What are the future effects on the building and landscape from the construction, design and engineering choices made?

The USGBC’s LEED process is designed to not only affect the building and construction trades, but to help in changing our mindsets about use, reuse, disposal, recycling and repurposing. As a voluntary system, it encourages the documentation and recognition of sustainable and innovative projects in the field of green building construction, science and engineering. The LEED certification program plays a large part in the invigorated growth of the sustainable building sector. Each time a project with potential LEED designation is under development, local markets are energized and community and consumer awareness grows.

— James McCain is a renewable energy expert and a future organic farmer.  He played a recent role in establishing the Tallgrass Grocery Co-Op in West Des Moines.

Michelle Peiffer

Renovating a historic 1930’s brick building presents many challenges. Renovating that same building to exceptionally high energy standards adds further layers of complexity to the project. Fortunately, for a vacant 5,000-square-foot brick storefront, developer Chaden Halfhill has not shied away from these challenges.

Storefront window facing east.

Few of these challenges are as convoluted as maintaining the delicate balance between the respect for the building’s historic character and the integration of modern energy-saving technologies. Halfhill’s renovation pilot project, Green & Main, aspires to LEED platinum certification as it transforms an abandoned grocery building into a first floor business and a second floor residence. As it turns out, windows are a particularly complex piece of the puzzle.

Balance Between Historic and Modern

Located in Des Moines’ Sherman Hill neighborhood, all 54 original windows, including two large storefronts, will be retrofit for energy efficiency in a variety of ways depending upon the condition, location and window type. While the default choice for most developers is often to replace historic windows in order to increase energy savings, most of the windows at Green & Main will be repaired, restored and specially renovated in accordance with the project’s energy efficiency and historic preservation goals.

“It is extremely important to find the balance between historic integrity and modern efficiency,” states Halfhill. “Windows are the place where historic preservation is combined with the goals in improving the efficiency of the building. Sometimes they are inclusive, sometimes exclusive.”

Halfhill recently explained the process of window restoration in detail during this month’s Green & Main Sustainability Renovation Workshop Series. “Windows are the biggest components to both preservation and efficiency,” Halfhill emphasized.

Storefront Windows

Exterior of the building, facing east.

There are two fixed storefront windows facing 19^th Street. These windows have been boarded up for a very long time. Removing the boards and restoring the windows will have a huge impact on both the appearance and the character of the building.

During the process of renovation, special care has been made to salvage windows and other pieces of the existing building for a similar use or for repurposing. During removal of the window infill boards, the original wood sill was uncovered. This wood sill will serve as a template for both the window reconstruction and from which the workers will replicate the angles of the old storefront window. While the original look and detailing of the historic storefront will be retained, new double pane insulated glass will be installed. The new panes are required under applicable preservation guidelines to match the appearance of historic storefront glass.

Row of small transom windows.

Above each of the two storefront windows and the entry vestibule, are smaller transom windows that allow more natural light into the building. The original glass had a translucent texture and several remaining pieces were salvaged intact. The salvaged glass was cleaned and sent to a factory where it will be incorporated into new double-paned assemblies. This will increase the R-value, or thermal resistance, while also maintaining the window’s historical appearance. Fortunately for our project, the manufacturer was able to locate new glass with a similar pattern to repair the transom windows that had damaged or missing panes.

Double-Hung Windows

The double-hung windows in the second floor apartment require a multi-pronged approach in order to meet historic preservation guidelines and energy efficiency goals. A double-hung window has two operable sashes – the top sash opens down and the lower sash opens up. This allows air to circulate effectively through a room and minimize the need for mechanical heating and cooling. The benefit in restoring historic double-hung windows is twofold. First, historic windows are “repairable” without specialized products or tools. Second, reuse of existing windows diverts material from landfills.

‘Anatomy of a Window’  See glossary below.

The first step in the process was removing sashes from the window frames. Historic double-hung windows are designed to be “deconstructed” and repaired. Deteriorated lead paint was removed from the windows using a chemical stripper, in accordance with Federal and state guidelines. Removal of the paint allowed workers to better assess the condition of each sash and make the necessary repairs.

Along the way, we also discovered that the weight pockets to the side of older windows have to be rebuilt. The missing sash rope, weights and pulleys have to be located, repaired or replaced to return each window to working order. The final step is to put the windows back together with new glazing, which is the material that holds the glass into the wood frame. It’s a long and exhaustive process to meticulously restore each window, yet Halfhill believes in the importance of keeping these windows out of the landfill.

To optimize the Green & Main building, a double-window assembly was designed. Inside each historic double-hung window will be a new double-hung window. This assembly will create an air-tight seal on the inside while retaining the historic appearance from the outside of the building. The new interior windows will be the same as the historic ones and installed in a new insulated wall construction adjacent to the original masonry wall.

The New Addition

It is important to note that window’s are a major component of a building’s “shell,” and one of the main points that must be examined in an energy retrofit. However, buildings behave as interactive systems where the foundation, walls, windows, doors, insulation and roof work together to keep energy in and weather out.

An important consideration to look at when integrating new windows with an existing building is to pay particular notice to the existing window positioning and reflectivity of the existing windows. With careful deliberation, the building can take advantage of natural wind patterns that can allow for natural cooling of the building. The focus of the window reflectivity is to take advantage of the opportunity to gain solar heat in the winter and keep the building cooler in summer. The new construction on the back of the building will have newer energy efficient windows, but they will correspond well with the positioning of the older windows to achieve maximum energy efficiency naturally: they will be designed to instinctually manage heat and heat loss.

Green & Main      storefront window.

All of the components touched on in today’s article require detailed, constant attention as the Green & Main Pilot project continues to evolve. Whole building awareness helps ensure major milestones and decisions to the building envelope itself are made and supported accordingly, resulting in building science at its maximum efficiency.

* * * * *

Anatomy of a Window Glossary

Upper/Lower Sash: A frame in which the panes of a window or door are set

Rail: A bar extending horizontally between supports, as in the framework of a sash

Head/Side Jam: The straight side of arch, door or window

Stiles: A vertical member of a panel or frame, as in a door or window sash

Parting Bead: A small narrow molding used to separate and guide the upper and lower window sash in Victorian double-hung wood windows

Meeting Rail: The rails in sliding sash windows, which meet in the middle of the frame

Window Sill: The flat piece of weed, stone, or the like, at the bottom of a window frame

– Michelle Peiffer is director of communications strategy for Indigo Dawn.

Ann Wilde

The construction crew at the Green & Main site enjoyed an extended summer, with temperatures in early October ranging into the 80’s with clear skies. This was an unexpected and much appreciated delay to our typical Iowa autumn. Soon it will be time to batten down the hatches and get ready for sub-zero temperatures when the crew will focus on the interior of the building.

Here’s what they’ve been up to…

Green Roof

Green & Main’s vegetative or green roof was installed on the spectacularly warm day of October 4, provided and delivered by Rooftop Sedums of Davenport, Iowa and installed by Silent Rivers’ staff.

Installation of the rubber membrane.

In preparation for the arrival of over 300 trays of sedum for the green roof, Academy Roofing first installed a membrane to serve as a protective layer between the actual roofing materials and the trays of live plant material, primarily sedum in this case. This membrane, known as a sacrificial membrane, is made of EPDM rubber, a type of synthetic rubber. EPDM roofing does not pollute run-off rainwater, and is an inert material, which has limited environmental impact during its manufacturing process in comparison to other membranes. Additionally, black EPDM is more cost effective as compared to a more reflective white, or TPO, membrane when used with a vegetative roof.

Tim Kepner of Silent Rivers installing the sedum.

Geothermal Energy System

Installing a geothermal energy system is a multi-step process that has taken shape at the Green & Main Pilot Project site over a period of months.

Several critical phases of a geothermal project need to be identified at the onset to assist in the successful installation and operation of the geothermal system. Some of the major phases are:

Loops of tubing.

• Drilling the actual wells, as well as the preparation needed to the soil/grounds to accommodate the loops of tubing which act as supply and recovery lines for the closed system.

• Excavation of the site around the well field, including the removal of the perimeters of a building foundation discovered buried underground, a 500-gallon steam tank and two cisterns.
  

  Looping for the geothermal well system.

• Connecting the well field of lateral supply and return lines to the building, requiring multiple assessments and adjustments. Research and implementation occurred regarding the addition of crushed glass and sand as backfill material, as well as sub-surface meters that will track temperature changes not only in the soil and fill, but also to measure the therms in the supply and return lines. Much of this research was initiated by the SWAP (Solid Waste Alternatives Program) grant in collaboration with the geothermal well installers and engineers, Barker Lemar.
  

  Drilling the well field.

• Backfill, preparation of the site and attention to effectively controlling soil by packing and rolling was essential in order to be ready for installation of the permeable pavers.

• Connecting the well field loops to the mechanical system is yet to occur. This will be accomplished later in the winter.

Geothermal System Gets Buried at Green & Main

For some months, two ends of the geothermal “tubes” have been visibly sticking above ground level at the Green & Main construction site. These were actually part of hundreds of feet of high-density polyethylene pipe, known as “loop”. This continuous system will circulate water through the loop and into the geothermal units, thus providing the geothermal energy system to the building through its underground foundation wall.

Green & Main’s geothermal energy system includes 11 vertical wells that were drilled 300-feet below the surface. After the wells were drilled, the initial tubes were installed to reach above the ground. Then, by exposing the ground about seven feet around the tubes and below the finished grade, the tubes were connected to form the system.

Bottles found while unearthing soil for the geothermal system.

On a historical note, dozens of glass bottles and containers were found during the excavation of the well field site. The bottles have been saved for future showing as evidence of lives past.

Roof on the Building Addition

The addition to the lower and main level of the Green & Main Pilot Project extends out at the back side of the building, pointing to the east. The roof of this addition will someday be the walk-out patio of the upper-level apartment. Once this roof has been completed, it will include additional vegetative roof plants and a decking system, providing an outdoor sanctuary for future second floor residents.

Sedum on the addition’s roof.

Both the roofing system on the main building and the addition will be an aesthetic bridge, creating a connection between the building and the surrounding site through the installation of unique water collection systems that accentuate this relationship.

Landscaping and Stormwater Management on the Grounds

Soil Amendments

The current soil of the Green & Main Pilot Project obviously has been altered in the century or so since it was untouched prairie grasses. To nurture the native plants in Green & Main’s landscaping, the soil was amended, incorporating more organic material into the existing soil. This will help restore the soil back to a more pre-settlement condition and it will help to absorb more water, thus making it more conducive to healthy landscaping. Similarly, combined with the native plants, the site will improve its capacity for ecological regeneration while serving as a pilot project for the Sustainable SITES Initiative.

Soil staging and layering.

Planting of the Site

The extensive native landscaping planned for Green & Main was completed by mid-October. The plants were provided by Allendan Seeds, who grew them from seed – as featured on WHO TV-13 – and installed by Greenbean Landscapes. In order to protect the site and avoid compaction of the amended soils, all construction equipment traffic was relegated to the city right of way and the six-foot perimeter around the building. This will allow the plants to establish themselves and ensure the porosity in the soils that will increase water infiltration and root development.

Plantings on site.

Plantings include such species as:  prairie dropseed, big bluestem, blue grama, buffalograss, little bluestem, switchgrass and pale coneflower. Indigenous plants are especially beneficial as their root structures assist with water infiltration and the cooling of ground water.  Developing the landscaping to provide a natural flow of rainwater was essential to our landscaping. As a result, rainwater will be guided through a bio-swale into the site’s rain garden to nourish the native plants.

Permeable Pavers

Paver bed for the parking lot.

Permeable pavers were placed over the geothermal well field at the end of the week of October 10. After the individual wells were connected below grade, the arduous task of filling a ten -foot deep basin with clean clay and layering the compaction to ensure a sound base for the pavers took place. Silent Rivers’ staff, along with Ron Gomis, worked through a long weekend to build the complex framework necessary to allow variables in grade for parking, as well as allowing easy access to the building. Hardscape Solutions of Iowa finalized these efforts by bringing its crew to construct the layers of gravel that will control water drainage from the Borgert Granite Paver system, the permeable parking system used in order to meet our stormwater management objectives.

Installation of pavers.

Rain Harvesting

While waiting for the completion of roofs over the carport and entry walkway, the H20 Rainwater Harvesting System was initiated on the concrete wall constructed between the parking area and the landscaping. The H20 HOG water tanks were installed and quietly await the future installation of the gutter system to highlight the ability to contain and reuse stormwater as a positive strategy for water conservation.

H2OG water tanks installed.

Many Thanks are Offered

During the final days of the installation as these various disciplines and projects merged together, many people visited the site to watch our progress. Key staff from Polk County Soil and Water Conservation and Iowa Department of Agriculture visited the site and helped hone installation details to ensure the project design and implementation were effectively produced, providing a model opportunity for urban non-point stormwater management systems. We are very grateful for their encouragement of the process.

Along with the many businesses and people who contributed labor, goods and services, the site was supported by Heartland RC&D, REAP, HRDP, IDALS, DNR, Metro Waste Authority, Iowa Waste Exchange, NRCS, USDA, City of Des Moines, NRBBOG, Polk County Soil and Water Conservation, Iowa State University CBER, IAMU and Growing Green Communities.

-Ann Wilde is a Des Moines marketing strategist and writer who also has a special interest in preserving and creating sustainable communities.

Michelle Peiffer

What is Geothermal Energy?

Geothermal Energy is heat (thermal) that comes from the earth (geo). The layers of the earth are heated in different gradients, originating from the 4,000-mile deep core, which has a temperature similar to that of the sun of around 9,000 degrees Fahrenheit (F). The heat gradually lessens as it reaches the surface of the earth, where the temperature of the top soil more accurately represents the temperature of the atmosphere. Just ten feet below the surface of the ground, the temperature of the earth maintains a constant temperature of 50-60 degrees F in all seasons. Geothermal heat pumps make use of the earth’s constant temperature as a natural source for heating and cooling.

Photo courtesy of the Department of Energy.

Geothermal Energy has been used for thousands of years, dating back as early as 10,000 years ago on this continent when Native Americans used hot springs for relaxation and cooking. Today, we use this natural heat source in a variety of ways ranging from highly technical geothermal energy plants that use hot water and steam to generate electricity to individual home and business use for heating and cooling.

How Does it Work?

In a residential or business setting, a geothermal well field is determined based upon the heating and cooling needs and the size of the building. This field is the area where geothermal tubing is placed into the earth – or in water such as wells or ponds – and where the temperate maintains a constant temperature throughout the year. The tubing can be laid vertically or horizontally, depending on the site. The tubing is most often made of plastic, although other materials such as copper have been used. The tubing is filled with a liquid that runs into the earth, where it is either heated or cooled, and then brought back to the surface to assist in maintaining a more constant building temperature.

For heating: In the winter, the cool water from the building is sent into the earth, heated to a temperature between 50-60 degrees F, and then brought back into the building where it transfers the therms in order to heat the building.

For cooling: In the summer, the warmer atmospheric temperature is transferred into the tubing liquid at the ground level and circulated into the earth where it cools and returns to the surface, bringing down the temperature of the building.

Photo courtesy of Geothermalgenius.org.

Geothermal heating is especially beneficial in keeping a building’s temperature at a comfortable constant throughout the year. During extreme weather conditions, only small amounts of additional heating or cooling may be necessary.

What are the Benefits of Geothermal Energy?

According to the U.S. Environmental Protection Agency (EPA), geothermal heat pumps are the most energy efficient, environmentally clean and cost-effective systems for temperature control. Geothermal pump systems burn no fossil fuel on site and generate far fewer greenhouse gas emissions than conventional furnaces. Even considering the emissions generated from the electrical power plant used to operate the system, total emissions are far lower than conventional systems.

Geothermal energy owners enjoy lower utility bills (25% to 70% lower as compared to conventional systems), lower maintenance and higher levels of comfort year-round. Since geothermal energy systems use no fuel on site, a potential source of poisonous carbon monoxide within the home or building is also eliminated. The waste heat removed from the home’s interior during the cooling season can be used to provide nearly cost-free hot water, resulting in a total savings of about 30% annually while lowering emissions even further.

According to the U.S. Department of Energy (DOE) Office of Geothermal Technologies, nearly 40% of all U.S. emissions of carbon dioxide (CO2) are the result of using energy to heat, cool and provide hot water for buildings. This is about the same amount of CO2 generated by the transportation industry. If the number of residential geothermal energy systems reaches 100,000, the result would be a reduction of greenhouse gas emissions equivalent to removing almost 59,000 vehicles off the road.

Why is Geothermal a Good Choice for Green & Main?

The ultimate goal for this pilot project is to transform a mixed-use business and residential building into a demonstration building that highlights energy efficient technology as it merges with historical preservation, all the while striving to reach LEED Platinum certification. Since Iowa has such extreme weather fluctuations, geothermal energy is a perfect fit because it will keep the building at a constant comfortable temperature, somewhere between 50-60 degrees F, thus greatly minimizing the project’s need for additional heating and cooling.

When developing the landscape, the parking lot was the perfect place to position a geothermal well field. Engineers selected the position because of the proximity to the building and the ability to create a vertical closed loop design, which means that the tubing is inserted in the earth vertically rather than horizontally.

Geothermal Energy Systems typically have the lowest life-cycle cost of any heating and cooling system. Heating and cooling costs for the 4,700 square foot Green & Main building are estimated to cost around only $2 a day. Geothermal systems and installation have dramatically improved over the past years and costs associated with the system have dropped significantly, with an average payback of around 7 years.

Meet our Partners in the Well Field Installation, Barker Lemar.

Barker Lemar headquarters, West Des Moines, Iowa.

The engineering consultants at Barker Lemar were instrumental in the development of the geothermal energy well field at Green & Main. From the very onset, they provided a series of earth borings to test the soil for the system installation. Barker Lemar has long been experts in environmental drilling and, in the late 1990’s, furthered their reach by installing geothermal tubing. They have set the benchmark for performance by investing time and energy into educating the consumer and designer on such topics as conductivity testing, drilling methods and implementing overall keys to a successful project.

Barker Lemar was a natural fit into the best practices component of the Green & Main project. The expertise provided in the well field directly correlated with the case study being developed as part of the Solid Waste Alternatives Program (SWAP) grant. Using recycled content as an insulator for the geothermal tubing and measuring temperature gradients between supply and return lines, the study will allow us to compare different insulators and then measure each one’s effectiveness. Tracy Lemar, vice president of Barker Lemar, explains that the pipes in the building can be very close in spots, so using an insulator is one way to increase efficiency by preventing the pipes from transferring the heat back and forth as it’s exiting and entering the building.

Lemar designed the insulation system and originally considered using tire-derived aggregate (TDA). After careful research, the decision was reached to bypass the TDA because of load requirements from the parking lot that sits above the geothermal well field. Recycled glass was ultimately chosen as the best aggregate product for performance. Crushed glass looks a lot like sand and was poured around all the piping and buried in the trenches where the tubes are close together. The heat conductivity will be measured by thermal couples in the building where data will be collected from the trench. The data will then be used to compare the glass against other typical materials, such as insulation board, to measure the differences in conductivity.

Lemar said that the reason he chose to be a part of the Green & Main project was due to the developer’s vision, Chaden Halfhill. “I was very impressed with his vision on how to transform a building that was probably one of the least energy efficient in town, to one of the most energy efficient. We are very excited to be a part of this project and wanted to be involved in the mission.”

– Michelle Peiffer is director of communications strategy for Indigo Dawn.

Upcoming Renovation Events

Are you interested in developing, designing or rehabilitating older buildings? Have you ever wanted to be an observer inside a construction project? Do you just enjoy a good story and making new friends? Well, clear your calendars because there are exciting renovation events happening this weekend in Sherman Hill.

The Green & Main building site is a real mess at the moment. There are geothermal tubes sticking out of the muddy terrain, the stairs have all been ripped out and the windows are covered with plywood – the perfect time to get an insider’s look at the building’s progress before the skeleton becomes hidden! Project developer Chaden Halfhill will be on-site to share his stories while working on the Green & Main project.

See where they unearthed a 500-gallon tank and happened upon a buried and long-forgotten trolley line. Feel the texture of the original window glass and wooden window sill while hearing expert advice on how we can restore these items while simultaneously making them ‘green.’

Experts in Attendance

Judy McClure, AIA, a preservation architect who was Iowa’s Rehabilitation Tax Credit reviewer for many years (including starting the State Tax Credit program), will share her knowledge of the challenges of incorporating sustainability with restoration. As a woman who wears many hats in her historic Sherman Hill neighborhood, she might even be able to tell you about the grocery store that existed before Green & Main (long rumored for selling underage kids alcohol and cigarettes).

Green educator and builder Bill McAnally will be on-site to share his experience in completely gutting and rehabbing a large building in Fort Dodge that turned into a highly energy-efficient community center for seniors. Working with local contractors and carpentry students, he will be sharing the objects they uncovered as well as explaining how to take down brick walls using ‘Viking’ technology.

The events this weekend will be informative and interactive; a perfect place to bring your own renovation questions to get them answered by local experts. Come explore the progress at Green & Main and network among some of the best in historic green renovation.

The events have been funded in part by a grant from the National Trust for Historic Preservation in conjunction with Iowa Heartland Resource Conservation and Development. Sponsored in part by Silent Rivers Design + Build. Our thanks go to these groups.

– Michelle Peiffer is director of communications strategy for Indigo Dawn.

• Direct other downspouts away from pavement and toward grassy, mulched or planted areas. You can attach a perforated plastic “French drain” pipe and bury it in order to cross a stretch of lawn with the drainage. If you don’t have gutters, dig a 3-inch to six-inch deep infiltration trench under the drip line and fill it with gravel to decrease erosion as well as standing water.

• Create a residential rain garden. A rain garden is a shallow depression in the ground that captures run-off from your driveway or roof and allows it to soak into the ground. Overflow from a rain barrel can be directed to rain gardens.

• Use a broom instead of a hose to remove plant debris and soil from your driveway.

• Reduce the size of impervious paved driveways, walkways, parking areas and patios. As repairs are needed to parking areas and walking paths, consider using permeable paving such as interlocking pavers or gravel.

• Instead of piping stormwater to a roadside ditch, install bio-swales to carry stormwater run-off. Many bio-swales are simply wide, shallow, vegetated depressions that are gently sloped and directed toward areas that can easily stand an influx of water; they are really nothing more than a grass-lined ditch.

• Design new construction to allow water to soak in to the ground. Decks should be built with gaps between the boards and bricks, and concrete lattice pavers or stones should be used for paved areas. If you’re building a new building, consider constructing a green roof.

– Ann Wilde is a Des Moines marketing strategist and writer who also has a special interest in preserving and creating sustainable communities.