Increasing Building Operating Efficiency through Proper Air Handling System Selection and Installation
From new construction to renovations and additions, improving energy efficiency continues to be a primary focus for today’s builders. Contributing to this demand is the fact that both businesses and property owners are beginning to familiarize themselves with materials and building practices, that provide increased efficiency and reduced environmental impact, to help save resources and money in the long term.
An integral part of increasing efficiency and reducing operation costs is minimizing air leakage. Often it’s assumed that air leakage only occurs if a building’s exterior walls are poorly sealed and insulated. However, significant energy loss can also occur if a building’s interior air handling system isn’t properly configured and installed correctly.
When properly chosen, insulation materials — including duct board, wrap, liner, and flexible duct media — will work together as a complete air handling system to provide outstanding thermal performance, virtually eliminate air leakage and absorb noise. To ensure these materials are working effectively, specifiers must take into account a building’s location, purpose, and any additional variables that may play into the overall operation of a property.
Location plays a key role in the selection of insulation materials for an air handling system. For example, when ducts are located in an attic or in an unconditioned space, during cold or warm weather, R-8 labeled duct insulation will help to reduce unnecessary energy loss. Duct insulation can also aid in controlling condensation issues in humid weather. Fiberglas ducts located inside the building envelope help assure the delivery of properly conditioned air. Following manufacturer recommendations to select the correct materials will help ensure the building is operating at its maximum efficiency level.
Other important factors to consider when building-out an air handling system include the functionality of a building and whether there are any green building requirements that need to be met. A residential or office building, for example, may require additional acoustic paneling to conceal duct noise compared to an industrial setting, where noise may not be as much of a factor. Builders looking to achieve LEED or other green certifications will require more careful material selection upfront. In either case, specifiers should work closely with their product representatives to identify materials that satisfy a building’s unique needs, while also meeting any budgetary limitations.
One of the most common mistakes specifiers make during the material selection process is cutting back on the thickness of the material (ex. installing a one inch thickness foam vs. the recommended 1.5 inch thickness). While a half inch may not seem like a big difference, reducing the thickness of the recommended product can actually alter the way an entire building operates.
Removing or reducing the amount of insulation used to insulate a building’s heating or cooling ducts requires the entire HVAC system to work harder, resulting in greater operation costs and energy expenditures. Poor duct insulation can also result in uneven temperature pockets throughout the entire building. To ensure maximum efficiency, it’s important that contractors follow the manufacturer’s installation guidelines. This will help protect the building’s heating and cooling system to avoid any problems down the road.
Once the appropriate air handling insulation materials have been identified, it’s important to ensure that the entire insulation system is properly installed since poor installation practices also contribute to reduced energy efficiency.
Improper installation of the specified material is one of the most common mistakes made during the construction process. Compressing or stretching insulation, either unknowingly or to save costs, compromises performance, resulting in decreased efficiency, as well as an increased risk of problems down the road. Compressing insulation reduces its measurement of thermal resistance (R-value) and the overall thermal performance of the assembly into which it’s placed.
In the same way, trying to stretch the insulation to fit around duct work can negatively impact the R-value and is likely to result in thermal gaps somewhere in the system. For best results, the insulation should completely surround the duct work with no compression, gaps, or voids. In addition, any utility or other penetrations through the assembly or cavity should be sealed with an air impermeable and, when required by code, qualified fire blocking material.
Following these steps to indentify the proper insulation products and ensuring that they are correctly installed will result in a complete air handing system that operates efficiently, reduces energy loss, and cuts back on long-term building maintenance and operation costs. For more information or to learn more about the importance of proper material selection and installation contact your local manufacturer.
Written by Dick Gebhart. In his role as Technical Manager of Engineered Insulation Systems, Dick Gebhart supports Owens Corning’s (www.owenscorning.com) commercial and industrial insulation products on technical committees, code compliance and filed applications. He has more than 30 years of experience in the industry.