www.energystarhomesamerica.com

Issue 9 Volume 3

September 2005

Reducing Construction Waste
by Jennifer Boyle
Each year in the United States, approximately 140 million tons of construction and demolition waste are sent to landfills. This “trash” amounts to more than half of total landfill waste, and as you in the construction industry know, much of it can be reused. There are several ways to reduce the generation of construction waste and reuse valuable materials…

• Optimize your design. This is the ideal way to cut down on construction waste, by simply creating less of it in the first place. An optimized plan is one that takes into consideration the most efficient shape and dimensions for the desired structure. For example, a higher wall-to-floor ratio (square footage of floor area divided by lineal footage of exterior wall) indicates a more efficient design. For houses up to 1024 sq. ft., a square is the optimal shape because it provides the most square footage within the least amount of exterior wall.
  Also be cognizant of standard dimensions of building materials. Most materials are available in even increments (2’, 4’, 8’…etc.) so the planning grid that accommodates the widest range of materials is a 2’ module. The same goes for building penetrations, (windows, doors…etc.) which should also be placed at even increments between structural components.
  If you’d like to learn more about optimizing a design, please contact Jennifer Boyle at jboyle@gwssi.com.
• Avoid purchasing excessively packaged materials. Reduce waste through conscientious consumerism.
• When remodeling, practice deconstruction over demolition. Before ripping out old materials, assess the condition and then feasibility of carefully removing any materials for potential reuse.
• Habitat for Humanity has several options for unused and pre-used building materials. They operate retail outlets called ReStores, which sell these materials at a discount. Check your local listings for a nearby Habitat for Humanity; use it as a means for responsibly disposing of extra materials, or find unique components and materials at a fraction of their regular cost.
• Freecyle. An easy-to-use, free internet recycling program, “freecycling” is a centralized clearinghouse for unused or unwanted materials. Local groups post messages for objects they wish to discard or request items they need. This is not a solution for large-scale production builders, but may serve the needs of smaller custom builders quite well.
• Look for local recyclers or dealers in reused and reclaimed materials. You may be surprised to find a local business that will come out and pick up the materials and save you a trip to the landfill.

Inspector’s Corner
Air Flow Within a Building
by Derrence Freeman, City Manager There are two types of air flow within a building: controlled and uncontrolled. Controlled air flow inside of a building is created by ventilation systems, fans, spot ventilators, make-up air and heating and air conditioning system flow. These mechanical devices are designed to help ventilate and/or distribute conditioned air throughout a building. Uncontrolled air flow is created by wind, the force of the stack effect (warm air rising) within the building, and leaks in the air distribution system. Uncontrolled air flow is affected by the size of the leak in the house envelope and pressure across the leaks. Air flow inside of a building creates positive and negative pressures that attempt to push conditioned air out of or pull unconditioned air into a building. Air will always find the path of least resistance, and for every cubic foot of air that exits a building, one cubic foot will enter. The most effective way to stop uncontrolled air flow is to install good air barriers and seal any penetrations and leaks through the envelope.
Building scientists are concerned  with the effects that air flow has on the durability, structural integrity, and energy efficiency of a building, and especially the effects upon occupants. Uncontrolled air flow can promote mold growth, spread pollutants and create negative pressures that can cause combustion appliances to backdraft. Negative and positive pressures can draw warm, moist air in contact with surfaces that are below their dew point, creating condensation which provides an excellent breeding ground for mold and mildew growth; both are known respiratory irritants. Negative pressures can also draw particulate pollutants, volatile organic compounds and soil gases into a building envelope. Negative pressures can cause backdrafting, spillage and flame roll-out from combustion appliances that use building air for combustion. Sealing the building tightly against air infiltration or exfiltration reduces air transported moisture which can deteriorate building materials in walls and ceilings.
Unconditioned air flow can reduce the energy efficiency of a building by increasing the air change rate that expands the volume of the building. This reduces the comfort level and forces the HVAC system to work twice as hard to heat or cool unoccupied spaces. An imbalance of air flow across interior or exterior walls, ceilings and floors can cause pressure differences if the supply and return to an area are not equal. Closed interior doors block the supply and return paths that can cause these areas to pressurize or depressurize. Buildings that have central return systems attempt to draw this missing air from the rest of the building and cause backdraft problems for combustion appliances. Additionally, without central returns, jumper ducts, transfer grills or undercuts under doors, these areas become pressurized, driving warm, moist interior air into the walls and ceilings leading to mold growth and potentially to the rot of the structural assemblies. Air flow plays a big part in the comfort of the indoor environment and treating the building as a system is your best bet for achieving desired comfort and safety..

Announcements:
LEED for Homes Pilot Program Teleconference
Dear Builders,
The US Green Building Council has begun the LEED For Homes Pilot program. This exciting new program carries great potential for the custom and production builder. GWS is a LEED-H provider and would like to introduce interested builders to this National program. GWS and USGBC are hosting a LEED For Homes Builders' Orientation Teleconference. We invite you to join us for three very interesting and informative conferences. James Hackler and Jay Hall of USGBC will be the primary speakers along with the GWS LEED-H raters. Please mark your calendar for the following dates.

Builder Orientation Teleconference Calls
Dial in Number: 866 469-3239 and access code: 87422076##
WebSite URL: TBA

Wednesday, September 28, 2005, 2 - 3 PM CDT (3 - 4 PM EDT)
Welcome / Introductions
Intro to USGBCD / LEED / Pilot
LEED for Homes - the Basics
Construction Cost vs Benefits
Q&A

Friday, October 7, 2005, 2 - 3:30 PM CDT (3 - 4:30 PM EDT)
Special Topics
* Multifamily
* Affordable Homes
* Production Homes (Sampling)
What are the Benefits of Building & Selling LEED Homes?
* Marketing / EEMs
How Much Will it Cost for a LEED Home?
* Builder and Homebuyer Costs
Discussion / Q&A

Wednesday, October 12, 2005, 2 - 4 PM CDT (3 - 5 PM EDT)
In-Depth Discussion of the LEED for Homes Rating System
* Example of a Single Family LEED Home
* Example of an Affordable LEED Home
* Example of a Multifamily LEED Home
In-Depth Discussion of Verification
Discussion / Q&A

The teleconference will incorporate a website presentation. If you are interested in participating in the teleconference, please contact Donney Dorton at ddorton@gwssi.com to get the website login and teleconference password.

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