Without tight ductwork, you may be heating places like the attic and the crawl space under your home. Spilling expensive conditioned air into unconditioned zones deprives your living spaces of warm comfort all winter and coolness in summer. It also drives up heating and cooling costs and degrades indoor air quality. When all the supply ductwork, return ducts, elbow joints, grilles and other components are added up, the total effective length of ductwork in a typical home can be up to 350 feet. Over the lifespan of a residence, this span of ducts and connections slowly deteriorates. The average leakage rate in homes currently exceeds 20 percent. In older houses, leakage may be as high as 75 percent.
The percentage of duct leakage in your home can be tested and established by an HVAC contractor. Problem areas usually include:
Leaky connections. At the time of original construction, joints between duct spans may have been simply pressed together then taped with duct tape to seal. Duct tape deteriorates with time, and these joints loosen and leak. All connections should be mechanically fastened with screws.
Supply duct leakage. Air in supply ducts is under positive pressure and leaks out through seams and pinholes in the ductwork. An HVAC system is balanced to deliver a specific volume of air. Supply leaks not only waste heating and cooling to a given room, they can throw the entire system out of balance.
Return duct leakage. Because returns draw air back to the furnace or A/C under negative pressure, return leaks pull air into ducts. Air sucked in from zones like the crawl space or inside wall voids may be contaminated and circulated through the entire home.
Degraded insulation. Ducts routed through unconditioned zones are insulated to loss of heat or coolness through the duct surfaces. Insulation deteriorated by age allows increased thermal loss and impacts room temperatures and energy efficiency.
In Terre Haute and the Wabash Valley since 1922, Paitson Bros. Heating & Air Conditioning is the established source for year-round heating and cooling expertise. Ask us about testing and sealing your ductwork to restore its original efficiency and effectiveness.
Our goal is to help educate our customers in Terre Haute, Indiana about energy and home comfort issues (specific to HVAC systems). For more information about ductwork and other HVAC topics, download our free Home Comfort Resource guide.
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Paitson Bros
1 (812) 232-2347
Serving the Wabash Valley, IN Area Since 1922