Duct Tape for HVAC Repairs: Smart Solution or Costly Mistake?
If you’ve got a leak in your heating, ventilation, and air conditioning (HVAC) system, you’ve already lost a good chunk of change on your skyrocketing energy bill.
So, when it comes to repairing the duct leakage, you won’t turn down an option that could save you a little cash.
If a quick internet search of the best tape for HVAC ducts has you considering using duct tape –– think again.
Before you make a costly mistake, read this guide to discover why duct tape may not be the best tape for your HVAC, and explore better alternatives for sealing your ducts to ensure efficient airflow.
Table of Contents
- Can I Use Duct Tape for HVAC?
- 6 Reasons Why Duct Tape Isn’t the Best Tape for HVAC Ducts
- Commonly Asked Questions About the Best Tape for HVAC Ducts
- Will Duct Tape Withstand Heat?
- What Kind of Tape Can I Use for HVAC Ductwork?
- What Is the Best Tape for HVAC Ducts?
- AAA Heating and Cooling: Portland’s Duct Cleaning and Maintenance Specialists
Can I Use Duct Tape for HVAC?
Don’t be fooled. Duct tape is not the best choice and should not be used on your HVAC ductwork.
To understand why duct tape is not a good choice for your ductwork, you need to understand its origin and composition.
Duct tape was developed during World War II by Revolite, then a division of Johnson and Johnson. The adhesive tape was made with a rubber-based adhesive applied to a durable duck cloth backing. Affectionately referred to as duck tape, this incredibly strong tape was used by the military for emergency repairs and to seal ammunition cases on the battlefield.
After the war, the tape color was changed from army green to silver, sold in hardware stores, and marketed for household repairs. In 1950 the tape began to be used in construction to wrap air ducts and the name “duct tape” came into use. However, in the last 50 years, reports have shown duct tape ironically failed repeatedly at patching leaky ductwork.
AAA Heating and Cooling has been in the HVAC business for over a half-decade. Our experienced technicians have witnessed the gradual move away from using duct tape on ductwork. We use only the best materials in our HVAC repairs. Request an appointment today.
6 Reasons Why Duct Tape Isn’t the Best Tape for HVAC Ducts
#1: It Doesn’t Seal Well
When trying to repair a leak in your air duct you want to seal the leak as much as possible. But if you’re using duct tape, it’s likely it won’t adhere to the surface at all.
A 2001 article by homeenergy.org advised sealing HVAC ducts may be the only use duct tape fails miserably at. The constant airflow of ductwork can quickly dry out the adhesive agent on duct tape, making it virtually ineffective at sealing to stop air leakage.
#2: It’s a Potential Fire Hazard
Duct tape is composed of three layers.
The top, silver layer is made of polythene plastic, the middle layer of fabric mesh, and the bottom layer is the adhesive.
The polyethylene top layer and the bottom adhesive layer are not flammable, but the mesh fabric in the middle layer is. The last thing you want to add to your HVAC system, which can be subject to extreme temperatures, is a flammable substance. Keep your home safe by avoiding this potential fire hazard.
#3: It Isn’t Built for Longevity
Research conducted in 1998 at Lawrence Berkeley National Laboratory by the Environmental Energy Technologies Division (EETD) tested a variety of tapes on sheet metal ducting. After heating and cooling the ducts to simulate the aging process, they concluded that duct tape becomes brittle, fails, and may even fall off completely.
“We tried as many different kinds of duct sealants as we could get our hands on. Of all the things we tested, only duct tape failed. It failed reliably and often quite catastrophically,” says Max Sherman, senior scientist and leader of the EETD.
#4: It’s Not Designed for High Temperatures
In the same EETD study, researchers performed a “bake test” in which sample joints were baked at temperatures from 140 to 187 degrees Fahrenheit. In many parts of the United States, HVAC systems are often placed in the attic where temperatures can easily reach 150 degrees Fahrenheit.
Scientists believe the adhesive and synthetic fabric reinforcement mesh deteriorate when introduced to high heat, causing the duct tape to fail.
#5: It Can Harbor Moisture
Condensation from cooling your air ducts can cause duct tape to fall off, especially if the ducts are not clean or free of moisture when the tape is applied.
Additionally, the mesh layer in duct tape can attract more moisture buildup, blocking the air from flowing freely through your duct.
Not only does that keep your ducts from working properly, but it also provides a breeding ground for mold, mildew, and bacteria.
#6: It Can Cost You Money In the Long Run
In 1995, testing was done by Arizona Public Service Company (APS) and Proctor Engineering Group (PEG) to assess the energy savings and peak demand reductions achievable on HVAC systems in homes less than one year old. They found many HVAC systems with obvious and easily eliminated leakages due largely to the use of duct tape at the connections in the duct system. The connections tested were reported as tight as they would ever be and were expected to leak more over time, due to duct tape failure.
When treated air is lost, your HVAC system works twice as hard to make up the difference and the problem becomes twofold:
- Your energy bills balloon
- Unnecessary wear and tear is placed on your HVAC system
That’s why the U.S. Department of Energy Office of Scientific and Technical Information has developed a best practices guide for HVAC retrofitting, which forbids using duct tape to seal ducts.
Commonly Asked Questions About the Best Tape for HVAC Ducts
Will Duct Tape Withstand Heat?
No, duct tape is not designed to withstand the high temperatures your HVAC system may be subjected to. Elevated temperatures above 140 degrees Fahrenheit can cause duct tape to dry, crack, separate from the adhesive, and fall off the duct completely.
What Kind of Tape Can I Use for HVAC Ductwork?
The purpose of using tape to seal your ducts is cutting back on air leaks.
Despite its misleading name and design, duct tape performed the worst among all the tapes tested in the EETD study on repairing ductwork.
Packing tape even finished ahead of duct tape in this study. The researchers noted the packing tape used has a thin, typically clear, polyester backing with an acrylic adhesive and is intended for use on ducts.
What Is the Best Tape for HVAC Ducts?
If it’s the ease and tidiness of tape you want, there are two types of tape recommended for leaky ducts, depending on the surface:
- Aluminum foil-backed tape: The foil backing enables it to withstand extreme temperature changes without shrinking or failing. The adhesive is made of acrylic and butyl which keeps it from drying out and becoming brittle. Foil tape works best and is often used on rigid duct board.
- Butyl tape: Also designed with a foil backing, butyl tape uses a thick layer of butyl adhesive which allows it to conform more easily to irregular shapes.
What Should I Do If I Have Holes in My HVAC Ducts?
Holes in your HVAC systems can result in you spending a fortune on your energy bill.
If you still want to save a little cash on the repairs, you may try using the recommended tape, or consider these options for your leaky ducts:
- Duct mastic/putty: Mastic is a glue-like material applied using a paintbrush or putty knife. If you are trying to seal a large gap or joint in your ductwork, use fiberglass mesh tape to cover it first, then paint over it with duct mastic.
- Injected aerosol sealant: Aerosol sealant is a sticky vinyl polymer that when sprayed into the ducts, automatically seeks out leaks and covers the hole. Once it dries, it permanently seals the leak. Developed at Berkeley Lab’s Environmental Energy Technologies Division, this product has been extensively tested under various conditions over two years with no noticeable change in its effectiveness.
These may provide a temporary solution, but if you want to ensure the job is done right, call the professionals at AAA Heating & Cooling. You can rest assured your HVAC system will be back up and running at optimal efficiency.
AAA Heating and Cooling: Portland’s Duct Cleaning and Maintenance Specialists
In today’s world, homes are built to last 30 years and if you plan to live in it for nearly half that time, your home may be the most important purchase of your life.
Don’t make the mistake of using duct tape on your HVAC.
For over 62 years, AAA Heating and Cooling has served the Portland area. Our team of professionals is equipped with the skills, knowledge, and experience to repair your leaky ducts and keep your HVAC in tip-top shape.
Trust family-owned AAA Heating and Cooling with one of the most important parts of your home.
Call us today.