Water-based putty duct sealant is the most effective choice for sealing ducts due to its easy-to-clean properties and long-lasting nature. Applying it with a brush or caulking gun is possible, but for the best results, it is recommended to hire a professional to internally seal the entire duct system.
If you are a DIY enthusiast, you can purchase putty, clean the outside of the air ducts, and apply the putty.
Alternatively, you can use high-quality adhesive tape, putty, or Aeroseal sealant. Each method has its own advantages and disadvantages, so let's take a closer look at which technique you should use and why.The best place to start is with a silicone-based duct sealant that is easy to apply with a putty gun. This sealant will cover cracks and holes and keep moisture away. Adhesive tape may come off or reach the air ducts over time, and condensation caused by temperature fluctuations will weaken the tape and cause it to break. Sealing your home's air ducts is an essential step in maintaining energy efficiency.
Sealing ducts from the inside out is a more complex process and will likely require professional help. The air ducts work by providing convenient ways for the air conditioner from your HVAC equipment to flow to the desired rooms. Sealing air ducts is often overlooked in many home improvement projects, but it can significantly increase or decrease the efficiency of HVAC systems. If you do an annual duct cleaning, you'll be able to spot leaks earlier and fix them before they become a major issue.
Using the fan, professionals will spray the inside of the duct system with a liquid rubber sealant, which will cover all the holes, cracks and joints that leak air. A practical option is to take a one-gallon bucket full of duct sealant and apply it directly with the help of a brush. This is considered internal sealing of the ducts using a technology and is done by an authorized professional. You probably don't need this type of service unless your ducts are very old and difficult to repair or replace.
If you suspect that your boiler isn't working properly or that some areas of your house don't have the same temperature as other rooms, you're likely to have some leaks in the duct system.
