January/February 2010
January/February 2010
Green Home Inspections and Retrofitting
Green Building, an obscure concept just a decade ago, has blossomed into mainstream consciousness. Today we see it in all media from Print, to Television, to the Internet. Building to Green Standards is a positive step but the real challenge to realize a sustainable future is retrofitting the massive volume of older existing buildings in this country and reducing the energy and resources that they consume. Not only do these older buildings strain the environment and power distribution infrastructures, but they can also have a potentially negative impact on the health of their inhabitants by having poor Indoor Air Quality (IAQ).
Older buildings make up a large portion of our nations building stock, and consume a disproportionate share of our energy resources. If we are to transform our culture into a truly sustainable one, we need to address the issue by retrofitting our existing buildings. Older buildings suffer from the effects of poor weatherization, inefficient appliances and mechanical systems, and neglected general maintenance. Also, many buildings have, to some degree, poor Indoor Air Quality caused by; a combination of the building materials or furnishings in the building “Off-Gassing” Volatile Organic Compounds (VOC’s), inadequate exchanges of stale interior air with fresh air from the outside, biotic contamination caused by high interior humidity, and cleaning and maintenance products brought into the building.
I have conducted numerous “Green Building Inspections” through the years and a pattern has emerged in the types of faults I identify in a typical older building. Each building has its own very unique challenges but they all share these similar issues that need to be resolved in their Energy Efficiency and their Air Quality.
The “Thermal Envelope” of the building typically presents variations of the following: no insulation or significantly under-insulated areas, poor-performing windows and doors, and insufficient attic ventilation. I typically find in the interior of the building the deficiencies due to inefficient appliances (the furnace, hot water heater, and refrigerator), incandescent bulbs installed in all of the fixtures, and leaky supply and return heating duct systems. These issues, as well as the occupant lifestyle habits, all contribute to the overall energy use by the inhabitants.
The common issues that I find during inspections that most impact the “Indoor Air Quality”: textile materials such as wall-to-wall carpet and furniture either releasing VOC’s into the air or acting as an incubator for allergens and a toxin sink for environmental pollutants, poor interior ventilation that causes stale air during the heating season or over humidification in bathrooms and basements that lead to biotic growth such as mold or mildew, off-gassing of recently installed building materials such as paint or construction adhesives, or storing and using many common cleaning products or solvents inside the building.
Energy Efficiency and Indoor Air Quality are just two issues of many that Green Building’s holistic approach to building and design addresses. These two issues, in the context of remodeling or renovating, are intertwined in a number of ways that require careful consideration. For example, when you improve the thermal efficiency of the building, you as a consequence reduce the naturally occurring air exchanges in the building. This means that you must be conscious not to degrade the Indoor Air Quality at the cost of improving the Energy Efficiency. Uncontrolled humidity can also become an issue caused by improving the Thermal Performance and decreasing the natural air exchanges in the building. These issues, humidity and decreased air exchanges, will typically require the addition of fresh air ducts, supplying fresh air from the exterior, and perhaps a dehumidification unit is needed.
All the items I mentioned in this article are what I would describe as “Low Hanging Fruit”. These are typically the least expensive issues to “Pick” during a renovation project that offer the highest level of environmental and financial return. These issues, when resolved, will give the owner of the building the fastest return on their investment through reductions in their yearly energy bills as well as future property value appreciation and real-estate marketability. Additionally, the occupants will also experience increased thermal comfort in all seasons, and a reduction of negative health issues that are generally associated with poor Indoor Air Quality such as Asthma, Allergies, and Chemical Sensitivity Syndromes.
These simple and relatively affordable energy reduction measures, after completed on our Nation’s aging buildings, will help make the local generation of renewable energy truly effective, and help point the way to a Sustainable Future.
Lance Bowen LEED AP, has been in the building industry for over a 15 years in many different roles including; cabinet maker, Project Manager, and Purchasing/Specification Manager for large national builders. He has been deeply involved in Green Building for almost a decade and started “New Harvest Homes” in 2004 as a dedicated “Design/Green-Build” company.