Start by sealing air leaks with putty or metal tape and insulate any ducts you can access (such as those in attics, mezzanines, unfinished basements, and garages). Never use adhesive tape, as it is not durable. Apply a layer of silicone caulk along both edges of the duct joint. Seal round ducts with aluminum foil tape, not adhesive tape.
Despite its name, it's not approved for duct sealing and doesn't hold up well in the long term. Experts believe that 20 to 30 percent of public heating, ventilation and air conditioning costs are due to leaks in ducts, representing a significant amount of money that translates into changes over several months. To avoid these situations, make sure the ducts are sealed, either the old-fashioned way (applying some adhesive tape, putty and insulation) or hiring a professional to blow liquid rubber sealant through the system. It is a thick, pasty substance that can be applied to the voids and leaks of the ducts with a caulking gun and a brush.
All joints in air ducts, air treatment systems and filter boxes are virtually hermetic using tapes, putties, liquid sealants, gaskets or other approved sealing systems. A much better long-term solution would be to ask a professional to apply liquid rubber sealant through the system. Sealing ducts with an aerosol-injected acrylic sealant is an effective way to eliminate leaks in ducts, when combined with manual sealing of other easily accessible areas. The more extreme the climate (hot or cold), the greater the advantages of sealing ducts.
However, in some cases, it may be more cost-effective to completely replace ductwork if the leaks are too much to be repaired. The self-made air duct sealing technique saves money, but it can be difficult for beginners, especially if they want to access hard-to-reach areas or when there are leaks hidden behind drywall. The ducts are the ones that distribute heat and air conditioning to the different rooms of the house and, often, these ducts have gaps in their connections, allowing the air conditioner to escape before reaching the intended room. So, in addition to improving airflow efficiency, why worry about sealing ducts in the first place? Sealing air ducts offers a multitude of additional advantages.
Seal HVAC ducts well to ensure that all air is supplied from a home's central HVAC air controller to the terminations of the supply grid without air leaks. Buy UL181 high-temperature aluminum tape in the duct section of a residential center and use it to seal the joints of round ducts. In humid conditions, the sealant needs more time in the tunnel to dry, requiring slower airflow or a longer tunnel. Leaks in the air duct will allow cold or warm air to escape before it reaches the desired living spaces in the house.
They will then pressurize the duct system with a fan and use a computer to analyze the data and determine how much air escapes through the ducts.
