McKinney Green Gardens

Date ant Time:  August 6, 2011  1:00 PM

Project:  McKinney Green Gardens

              Gabe Nesbitt Park

We have had one of the worst heat spells and severe draught conditions in Dallas/Fort Worth history this summer with temperatures well over 100 degree F for over 35 days in a row.  This one acre demonstration garden, which is a research garden funded by the City of McKinney and the Texas AgriLife Research and Extension Urban Solutions Center, gave me the opportunity to appreciate the diversity of draught tolerant species of vegetation that will survive in conditions of extreme temperature and draught.  The garden is an illustration of how good planning and design and proper plant selection can reduce water consumption and be inherently sustainable.

intereactive map (see webpage)

Surprisingly, residential garden design using draught tolerant plants can be very aesthetic.  The park layout of this demonstration garden consists of six small gardens along winding paths which have been planted using different turfgrass areas, ornamental grasses and plants.  The website (http://mckinneygreengardens.tamu.edu/) goes into detail regarding irrigation requirements and systems as well as the different types of plants and grasses that have been planted.  The map that is included in the website is interactive and pointing to each of the bubbles on the map shows the type of plant or irrigation system provided.

shrubs

ornamental grasses

A porous pavement has been included in the walkway.  This captures the stormwater and allows it to seep into the ground to recharge the groundwater.  This eliminates the need for retention ponds, swales and other stormwater management devices.  Decomposed granite also allows water to drain through, is very organic and environmentally safe.  It can be used for walkways or driveways and as a mulch or base for pavers or stones.

Following the a link to the web page:
http://mckinneygreengardens.tamu.edu/

McKinney Green Building

Date ant Time:  August 6, 2011  12:00 Noon

Project:  McKinney Green Building

This 59,662 square foot, 3 story office building was not open but we had an opportunity to tour the exterior.  It has 188 parking spaces for a ratio of 3.18 per 1,000 square feet.  It was completed in 2007 and is a LEED Platinum Certified building.

south elevation

west elevation

Some of its sustainable features include:

• Over 72% energy use reduction over established standard.
• Stone, brick and stucco exterior.
• Use of recycled materials
• High insulation R-value for roof (Energy Star) and walls.
• Insulating glass.
• Window shading in all orientations.  (included but not necessary at the North orientation)
• A photovoltaic system to provide approximately 10% of electrical demand. (can be expanded)
• A solar hot water system.
• 120 Geothermal wells with 8 miles of piping located under parking lot.
• Occupancy and daylight sensors for lighting.
• Open plan to allow for daylighting reaching most of the interior.

 

open office - typical floorplan

• Energy conserving lighting.
• Waterless urinals, low-flow toilets and faucets. (waste water from building is reduced by over 50%)
• Draught tolerant landscaping.
• Plug-in station for electric vehicles.
• 6 hybrid parking spots.
• Bicycle parking and storage.
• Underground stormwater storage system for rainwater harvesting:  rainwater drains into permeable pavement system and down through sand and gravel bed and then directed to the storage system.
• Above ground water storage tanks (9200 gallons each) collect roof rainwater for landscaping.

permeable pavers

• Low or No VOC paints, adhesives and sealants
• Under floor air distribution system.
• Formaldehyde-free wood panels and FSC certified wood products.
• 46% of materials manufactured regionally and 11 percent with post-consumer and post-industrial content

Following is the architect’s (HDR) web page for the project
http://www.hdrinc.com/portfolio/mckinney-green-building

Pat Lobb Toyota of McKinney Texas

Date ant Time:  August 6, 2011  10:30 am

Presenter:  Pat Lobb

                  Pat Lobb Toyota of McKinney

This is the world’s first auto dealership to receive LEED Certification.  The project was designed by Gensler Architects and is rated as LEED Silver.  Sustainable features incorporated in this design are being used by other Toyota Dealerships which are also LEED Certified.  The estimated savings include 20% less energy, 30% CO2 savings and 50% less water use.  Mr. Lobb estimated a 7% increase in the cost of the project with a payback of 3 years which is an excellent ROI.  He saw it as a good business decision to add the sustainable features.  He did not see the inclusion of a photovoltaic system which would have a 21 year payback as cost effective in Texas at the present time due to lack of state tax incentives and utility rebates.

exterior view of facility

Some of the sustainable features of the dealership include:

• High Efficiency A/C systems.
• No VOC paints.
• Floor tile and carpet made from recycled materials.
• Energy conserving lighting fixtures.
• Building orientation and shading of windows.
• Insulated exterior aluminum panels made from 95% recycled aluminum
• Insulating glass
• 8660 gallon water cistern collects 16,000 gallons per month of condensation from 12 rooftop air conditioners and 7 interior systems.  Used to supply water for landscaping.

cistern

• Draught resistant landscaping (Buffalo Grass)
• Car wash uses a ‘closed loop recycled system’ of reverse osmosis water which cleans the water for re-use.  This saves 66% of water (over 1,548,000 gallons per year) used for car wash operations.
• A car wash rinsing system saves 72,000 gallons per year
• No blowers required for the car wash due to clean water
• Heat generated from waste oil.

waste oil recycling

• Recycling program: batteries, tires, paper, waste oil, etc.
• Insulated roofing system with white, highly reflective membrane.
• Parking lot concrete contains 20% recycled fly ash which increases reflectivity.
• Construction recycling:  80% of construction debris was recycled.
• Green wall:  Japanese Creeping Ivy on wall helps keep building cool.

 There is some storm water retention that was included as part of the parking lot design.  This is used to mitigate flows into the city storm water system.  A new parking lot being planned will include a cistern and that water will be re-used.

interior view of dealership

The vehicle maintenance area includes air conditioning which is unusual in dealerships.  They used a dropped ceiling in the space for a quieter shop and to reduce conditioned space.  An automatic rolling door is used to conserve energy.  

vehicle maintenance area

Following is a link to their website:

http://patlobbtoyota.com/

Sustainable Structures of Texas

Date ant Time:  August 6, 2011  8:00 am

Presenter:  Lee N. Hall, P.E., LEED AP

                  President

                  Sustainable Structures

Lee gave us a tour this morning of his ‘TERRAcourt Home’, in the Montgomery Farm Development,  which is the first LEED Gold certified home in Collin County with an impressive HERS index of 49 (Energy Star requirement is 85) and a tightness coefficient of .08 (76% higher than industry norm).  It also received the EPA’s Indoor airPlus designation.  Lee mentioned that he can guarantee an average monthly electrical energy cost of $102/month for the home.  The home was completed in 2011, is over 5000 square feet and was estimated to cost approximately $215 per square foot to build.  The home is currently on the market with an asking price of $2.5 Million.

TERRAcourt Home

With an interest in using ‘off the shelf’ technology when building the home, Lee opted to use ‘Advanced Framing Techniques’.  The wall construction includes 2x6 studs at 24 inches on center in lieu of standard construction which is 2x4 studs at 16 inches on center.  This cuts ‘thermal bypass’ which is heat transfer through the wood studs and also increases the depth of insulation that can be accommodated in the wall.

wall construction

Some of the sustainable features of the home include:

• Standing seam roof with seams rolled together.  (This roof is properly oriented with what looks like an acceptable slope and is ready to received a photovoltaic system with a mounting system that can be easily attached to the standing seams)
• The use of low VOC paints and adhesives
• Rainwater capture system that collects rainwater in a 2000 gallon bioswale rain garden. (see photo)

bioswale

• A whole house ventilation system
• Stone facade
• Wall insulation value of 19.4 plus 5 for sheathing.
• Foam attic insulation.
• LED lighting (exterior and interior – 75% of lighting)
• Window U factor of .32
• Fan in garage turns on automatically to expel vapors.
• Exhaust fan in bathroom uses humidity sensor to turn on. (can be bypassed)
• Water temperature can be set in bathroom for shower.
• Native grass (Buffalo Grass), plants and rescued trees from earlier on-site and off-site development.

Some features of the home which could have been done differently to improve its energy performance:

• The ‘eyebrows’ over the windows could have been re-designed to actually shield the windows from direct sunlight.  A ‘shading study’ on the windows could have been done that would tell the designer the extent of shading required based on the orientation of the windows. (see McKinney Green Building)
• The house uses 3 – 3 ton Air Conditioning units with SEER’s of 16.5.  Currently there are units with SEER’s as high as 23 on the market.

window with 'eyebrow' shading

The  Montgomery Farm Development is focused on designs that are sustainable.  In the Master Plan (see below) they have included wide open spaces with greenways and trails that connect residents to schools, work, shopping and each other.  The patchwork of greenways includes protected meadows, woodland gardens and wildlife preserves.  In this development they have set aside 20 acres for a LEED pilot project with USGBC. They are part way through the approval process; however, they have a problem with the density factor for the development.  LEED-ND requires a density of 7 units per acre and an FAR (floor area ratio) of .5. The Stage 1 approval process for the development already cost over $30,000.  

Montgomery Farm Master Plan

Following are links to the websites:

http://ssotx.com/index.html

http://montgomeryfarm.com/

SynergyFish - Aquaponics

Date ant Time:  August 2, 2011  8:00pm

Presenter:  Dave Pennington

                  SynergyFish – Aquaponics

Dave’s expertise lies in Aquaponics.  I had the opportunity to hear Dave’s lecture at the Renewable Energy Roundup at Fredericksburg Texas last year and was very impressed by his knowledge of the subject.  There are 6 videos of his Fredericksburg presentation on YouTube.  The following is segment 1 of 6.

A type of Aquaponics called ‘Chinampas’ was used back in 1500 by the Aztecs in their capital city of Tenochtitlan.  At the time, this was the largest city in the world.  Fish were raised in the channel and the larger willow trees and posts were used to retain the soil at the elevated growing beds.

Chinampas

At the present time 85% of our water goes into agriculture and almost 80% of the world’s fisheries are fully to over exploited, depleted, or in a state of collapse.  Right now, Aquaculture provides about half of all fish production.  Per capita consumption of fish will continue to rise as 3^rd world nations become wealthier.  Aquaponics would be able to conserve water used for irrigation as well as provide protein from the harvesting of fish.

Aquaponics is a truly sustainable food production method that uses just a fraction of water normally used for agriculture and aquaculture.  It efficiently uses a resource considered waste, eliminates chemical fertilizer pollution and relieves pressure on ocean species by providing fish protein.  It also allows for efficient local production of food.

small Aquaponics garden

Aquatic species that can be used in Aquaponics include:

• Tilapia
• Goldfish
• Catfish
• Trout
• Bass
• Freshwater Prawns (Shrimp)
• Barramundi, jade perch, etc.

Tilapia is one of the fish better suited for Aquaponics.  It produces between 500 and 1000 eggs every 2 or 3 weeks.  They can be confined up to one pound of fish per gallon of water in a rearing tank (not including grow beds).  The fish are omnivorous, hearty, easily bred and fast growing.  They can be fed organic pelleted feeds, black soldier fly larvae, vegetable scraps, duckweek and other ‘weeds’.  The black soldier fly larvae convert garbage into grubs for animal feed.  The grubs contain high amounts of protein and fast.

another example of a small Aquaponics garden

Dave has been developing a construction material called ‘Papercrete’ which is a made of recycled paper, Styrofoam and Portland cement.  It has good structural and insulating properties.  He estimates an R-factor of 3 for the material and is constructing domes formed by inflating a ‘balloon’ as a form and applying the Papercrete to this form.  He is also working on a Community Garden Coalition project in S.E. Dallas that will include an Aquaponics greenhouse.  You can see this project at:

www.facebook.com/Urban-Comminity-Garden-Coalition

Examples of Aquaponics developments can be found at:

http://bioshelters.com/

http://www.aquaranch.com/

http://herbanfarms.com/

Dave Pennington’s web site is:

http://aquaponicscommunity.com/profile/DavePennington

buildingcommunityWORKSHOP

Date ant Time:  August 2, 2011  7:00pm

Presenter:  Brent Brown and Benji Feehan

                  buildingcommunityWORKSHOP

The buildingcommunityWORKSHOP (bcWorkshop) is a 15 person Dallas based nonprofit community architectural design center specializing in sustainable design.  The Center seeks to improve the livability and viability of communities.  They bring design thinking to areas of the city where resources are most scarce.  Their focus is about ideas, about making connections to things that need to happen, and about getting things done.  It means getting involved with community based design which means engaging the client and the communities that they are working with.  Bringing in as many people from multiple disciplines and exposing them to a process from development to design to construction. The bcWorkshop recognizes that it must first understand the social, economic, and environmental issues facing a community before beginning work.

bcWorkshop planning study

Brent mentioned that the most fundamental aspect of sustainability is Ethics.  bcWorkshop is interested in Architecture to help people.  Environmental design is the background of their work.  They label their practice as ‘public interest design’ and it is based on a process of engagement with the community.

One of the projects they have worked on is the Congo Street Green Initiative.  Funding for the project came from bond money and HUD.  Congo Street is a 19 foot narrow street with 17 single-family homes and duplex houses that were built before 1910.  It is located just a few blocks from the ‘State Fair’. 

Congo Street - early photo of development

Many living there are long time residents and some are descendents of former renters.  They had 5 families on the street when they started the project.  The project entailed maintaining a sense of community as each resident expressed a desire to remain on Congo despite the need to repair their home.

recent photo of Congo Street development

Taking into consideration the amount of time it takes to renovate a home, a residence called the “Holding House” was built.  A resident would live there while their home was being renovated or rebuilt.  The house has achieved LEED Gold rating.  Another home has achieved LEED Platinum and each home will either meet USGBC REGREEN standards for renovations or LEED for Homes certification for new construction.  They have also been working with a landscape architect to define landscape areas along the street.  Each area in front of a home will have input from the resident and will contain vegetation that is native to the area and draught tolerant.

a renovated home on Congo Street

Here is a link to the Congo Street blog:

http://bcw-congo.blogspot.com

 Those interested in touring the Center are invited on Friday’s at 12 Noon.  Call ahead of time to make sure they are available.

bcWorkshop is located at:

2814 Main St., suite 102

Dallas, TX  75226

Phone:  214-252-2900

Following is a link to the bcWorkshop web page:

www.bcworkshop.org

Alan Hoffmann Company

Date ant Time:  August 2, 2011  6:00pm

Presenter:  Alan Hoffmann

                  The Economics of Green

                  Alan Hoffmann Company

The Alan Hoffmann Company is a home builder and developer based in Dallas.  Alan specializes in building homes that are highly energy efficient.  Some of his homes have obtained the LEED Platinum rating. 

LEED certified home

The way Alan has chosen to build his homes was inspired by homes in Ibiza Spain.  His grandfather was from this small island.  These homes typically are constructed of high thermal mass walls as much as 3 feet thick.  The thermal lag through these walls evens out temperature extremes.  In Ibiza, which has a climate similar to Austin, many homes do not require air conditioning.

Alan took what he learned from Ibiza and incorporated it into his home designs here in Dallas.  The method he is using is a stay-in-place insulated concrete forming system known as Insulated Concrete Forms or ICF’s which are typically 9.25 inches thick.  This type of system was introduced in Europe in the early 1970’s.  This building system is highly insulating and creates a very tight home with low air exchanges.  Low air exchange translates into savings in A/C energy usage.  Since the walls are made up of cast-in-place concrete, the homes are very resistant to strong winds.  Some of these homes have withstood tornados with only minimal damage.  Some attributes of this type of construction include:

• Low maintenance costs
• Resistance to termite infestation
• Life safety – resistance to high winds
• Easy integration with existing construction
• Sound attenuation

ICF - Insulated Concrete Form

 In designing his homes, Alan locates the mechanical system on the ground floor.  This eliminates the overheating of the fan coil system and duct runs in hot attic locations.  A/C systems with SEER rating of 21 and humidistats that monitor humidity are typically included in his home designs.  He also includes whole house water purification systems to reduce chlorine and other contaminants.  Once the building envelope is dealt with and an efficient HVAC system is integrated into the design, energy consumption is greatly reduced.  Once you have optimized the building envelope, supplemental renewable energy systems can be added to the home such as wind, solar water heating and photovoltaics in a much more cost effective way.

Using this type of system typically adds approximately 6% to 8% to the cost of a home as compared to a conventional stick built (balloon framed) home that uses fiberglass bat insulation.  Additional cost is recouped through lower energy costs.  Roof construction is wood frame as the economics of steel construction is not feasible.

Alan is currently developing a community of 22 homes built with ICF’s that includes an underground cistern to capture rainwater runoff.  This water in turn will be used to irrigate the landscaping.  Dallas actually averages more rain than Seattle, although the rain tends to occur in heavy downpours in the spring.

Following is a link to the Alan Hoffmann Company:

http://www.concretehomestore.com/

McCommas Bluff Sanitary Landfill, Dallas

Date ant Time:  July 30, 2011  12:00Noon

Tour Guide:  Jon Picha

                    McCommas Bluff Sanitary Landfill

This is the largest landfill in Texas and is owned and operated by the City of Dallas.  It accepts waste from City collections as well as commercial haulers.  The area owned by the City encompasses 2000 acres of which approximately 1000 acres is currently being used by the landfill.  The landfill is bordered on the east by the Trinity River.  Much of the site is in a flood plain area.  The elevation of the landfill begins at approximately 320 feet and will extend up to a maximum of 550 feet.  Presently, they are up to 490 feet elevation.

McCommas Bluff Landfill Site Plan

Approximately 600,000 tons of waste is generated annually by the residents.  It is estimated that the landfill can serve current needs for about 120 years; however, new technology will possibly replace the need for landfills in about 50 years.  Currently ‘Dirty MRF’ systems for recycling waste are being tested in California.  A ‘Dirty MRF’ system accepts a mixed solid waste stream and then proceeds to separate out designated recyclable materials through a combination of manual and mechanical sorting.  The City of Dallas is investigating using this system to recover recyclable materials.  With this type of system a separate trash bin for recyclable materials would not be necessary.

a 'Dirty MRF' system for recycling of domestic waste

The McCommas Landfill is using ‘Enhanced Leachate Recirculation’ which introduces liquids into the landfill to increase production of landfill gas and also helps speed up the waste decomposition process.  When water percolates through waste, Leachate is the liquid that is produced.  Depending on the waste in the landfill, Leachate can be harmless or toxic.  There are currently water retention ponds at the site.  The water from these ponds is being pumped into the landfill.  Leachate goes to a storage tank and eventually gets pumped back into the lake.  It is not used for anything else.

landfill showing leachate piping

The leachate system is designed as a ‘layered’ system.  Leachate pipes are embedded into the landfill at every two ‘lifts’.  Each ‘lift’ being approximately 20 feet.  This means there is a new water line every 40 feet.  Every other ‘lift’ also gets a gas line.  There is a layer of ground glass at each ‘lift’ that helps percolate the water into the soil.  You can see where the gas is being extracted along the perimeter of the landfill.  There is a system for monitoring if there is gas escaping from the site.  Following is a picture of the gas extraction pipe.  These can be found along the perimeter of the landfill.

gas extraction pipe

Currently, Dallas collects approximately 5 Million cubic feet of landfill gas daily.  This gas is sold to a public utility for royalties in the amount of $1.2 Million per year.  If you include tip fees, the landfill generates revenues of approximately $15-$20 Million annually for the City of Dallas. 

Here is a short video that shows an example of a ‘Landfill Gas to Energy Power Plant'.

Following is the web page for the landfill:
 http://www.dallascityhall.com/sanitation/mccommas_bluff.html

River Legacy Living Science Center

Date ant Time:  July 30, 2011  10:00am

Tour Guide:  Anne Alderfer, Master Naturalist

                    River Legacy Living Science Center

The River Legacy Living Science Center was built in 1988 through a partnership between the City of Arlington and a private foundation as an education center and is at the gateway to River Legacy Parks in North Arlington.  River Legacy Park encompasses 400 acres and includes over 16 miles of trails.  The building was designed by Jones Studio and includes various sustainable features.

interior view of Science Center

Some of the sustainable features in the Science Center and grounds include:

• Modular pavers in the parking lot that are porous and shaped to allow air and water to recharge the soil.
• The decking outside of the building is made of a composite of reclaimed plastic and waste wood.  It uses no virgin wood and is 100% recyclable.
• The restroom wall tiles in the building are made from recycled crushed auto windshields.
• Composite lumber used in the building is a mix of wood shavings that come from small diameter trees of second or third growth.  It uses much of the tree that is ordinarily thrown away.
• The carpet uses synthetic fibers and backing that can be continually recycled and reused.
• The building uses a grey water treatment system that reduces waste water to a clear, odorless liquid in 24 hours.  This water is used in the sprinkler system.
• Trees were relocated and parking lots laid out to minimize impact.
• The nature trail has a mulch covered walk to minimize foot traffic impact on native soils.
• Path surfaces were made from granite dust which is normally disposed of in the quarrying process.  This allows more air and water to penetrate the roots.
• Native plants that are less demanding of water and fertilizer were planted.
• Root watering crystals were used.  They retain moisture thereby requiring less watering of plants.

butterfly display in the Science Center

Anne Alderfer gave us an interesting tour on a nature trail that winds along the vicinity of the Science Center.  This part of the park is in ‘bottomland’ as can be seen by the dense vegetation and by the large trees that grow here.  Anne pointed out the effects that our current draught is having on the vegetation and the mechanisms that plants use to cope with this kind of stress.  Also, she pointed out that some plants, like the Asian Privit, is very invasive and is being removed from the park.  

nature walk trail

On a large Cedar Elm Anne pointed out that the sap suckers (woodpeckers) were attracted to this tree because it was sick. She pointed out how you can tell how they leave their markings on the tree in more of a regular pattern on the bark whereas insects would leave more of a random pattern.  Also, she mentioned that the woody material that is left over from downed trees and limbs becomes a great habitat for creatures and also eventually decomposes and recycles back into the forest floor.  The lake by the Science Center has Tilapia fish and there are Bobcats have been spotted in the park.

To control erosion on the banks of the river that is now dry, they have used rocks held by a wire mesh type of material.  This is more of a sustainable alternative than concrete retaining walls.  See picture below.

Following is the web page for the River Legacy Living Science Center:

www.riverlegacy.org