As an expert in the HVAC industry, I have been asked countless times about the best way to seal ductwork. It's a valid question, as the efficiency of your air conditioning system depends on properly sealed ductwork. In this article, I will discuss the pros and cons of using tape and putty to seal your ducts and provide my recommendation for the best option.
The Importance of Properly Sealed Ductwork
Before we dive into the specifics of tape and putty, it's important to understand why having properly sealed ductwork is crucial. The main trunk line is the main air conditioning supply system and requires adhesive tape for the smaller duct lines that branch out from there.Closure systems used with flexible air ducts and flexible air connectors must comply with UL 181B and bear the 181B-FX mark for pressure sensitive tape or 181B-M for putty. If you are using putty to seal joints in fiberglass panel ducts, it is recommended to use fiberglass mesh tape for all joints. This is advised by Hardcast, a leading manufacturer of HVAC products. Foil-Grip butyl tape is also a popular choice for use with galvanized steel ducting, duct plates, or flexible ducting.
Tape vs. Putty: The Pros and Cons
Now let's take a closer look at the benefits and drawbacks of using tape and putty to seal your ductwork.Tape
Professional HVAC tapes are specifically designed for sealing ductwork and can withstand the test of time.They are also easy to use and require minimal clean-up. However, they can be more expensive than putty sealant. Another factor to consider is the shape of your ducts. Tape tends to work better on round ducts than on the sharp, irregular corners of rectangular ducts. This is something to keep in mind when deciding which option is best for your specific ductwork.
Putty
Putty sealant is a more affordable option compared to tape.It is also less messy and easier to apply, making it a popular choice for DIY projects. However, there are some concerns about the longevity of the seal when using putty in the joints between duct sections. Closure systems used in rigid and fibrous glass ducts must comply with the UL181A standard and bear the 181A-P mark for pressure sensitive tape, 181A-M for putty or 181 A-H for heat sensitive tape. You can use Mastic sealant or aluminum tape. Below is a detailed list of some of the benefits of both.
At that time, you can fix the duct to the cover and properly seal the joint before repairing the roof.
My Recommendation
After weighing the pros and cons of both options, my recommendation for sealing ductwork is to use professional HVAC tape. While putty may be a more affordable option, it may not provide a long-lasting seal and could lead to air leaks in the future. Tape, on the other hand, is specifically designed for sealing ductwork and has been proven to withstand the test of time. However, if you do choose to use putty, make sure to follow the UL181A standard and use fiberglass mesh tape for all joints in fiberglass panel ducts. This will ensure a proper seal and compliance with industry standards.In Conclusion
In conclusion, properly sealed ductwork is crucial for the efficiency of your air conditioning system.While both tape and putty can be used to seal ductwork, my recommendation is to use professional HVAC tape for a long-lasting and effective seal. If you do choose to use putty, make sure to follow industry standards and use fiberglass mesh tape for all joints. By properly sealing your ductwork, you can ensure that your air conditioning system is running at its best and save money on energy costs in the long run.
