How to Properly Seal and Insulate Your Ductwork

Ductwork is an essential component of a central HVAC system. Unfortunately, it also tends to be the part of an HVAC system that is most neglected. Issues like leaks and dirty air ducts can have a major negative effect on HVAC performance, energy costs and indoor air quality. Having your ducts cleaned and/or sealed can greatly improve your system’s efficiency and also your comfort. Here, we’ll explain how professional duct cleaning and sealing works and what benefits it can provide to your home.

HOW OFTEN SHOULD DUCTS BE CLEANED AND RESEALED?

The ductwork in most homes usually lasts for around 25 to 30 years. However, leaks and other issues can crop up at any time. This is why experts recommend having your ductwork professionally inspected every year when you’re having your heating or air conditioning serviced. In homes with a basement, the majority of the ducts are hidden within the basement ceiling.

Unless it’s a suspended ceiling with tiles you can remove, a technician will usually need to use a remote camera to perform the inspection. If the ductwork is in the crawl space or attic, the technician can just perform a visual inspection to check for gaps, holes and other damage. However, they will still usually use a camera as well to look inside the ducts and determine if they need to be cleaned.

Most experts recommend having your ductwork professionally cleaned every three to five years. Unfortunately, this really isn’t something you can effectively due yourself since it requires specialized equipment.

It’s also recommended to have all of your ductwork resealed by an HVAC company at least every 10 years. In some cases, your ductwork may need to be resealed after just a few years. This is the case if it has started to sag or the foil tape or mastic that connects each piece is coming loose. If the ducts are fairly old and/or have lots of damage, simply replacing them will always be the better option.

HOW PROFESSIONAL DUCT CLEANING WORKS

Duct cleaning is usually performed using a high-power industrial vacuum. This allows the technician to fully remove all debris from inside the ducts and collect it without making a mess.

The first step is for the technician to seal up all of the vents and registers with plastic. This is necessary to allow the vacuum to create negative pressure inside the ducts so that it can easily suck out all of the debris. Sealing up the vents also prevents dust and debris from getting blown around the house.

Before attaching the vacuum to the duct system, the technician will usually use a special rotating brush to loosen up all of the debris to ensure that the vacuum can remove it all. They will then either cut a hole in the main trunk duct and attach the vacuum this way or attach it to one of the supply or return vents. Depending on the layout, location and size of the duct system, the technician may need to access it from several different points to ensure that the entire system gets fully cleaned.

OPTIONS FOR RESEALING LEAKY DUCTS

Which option is best for resealing a ductwork system depends largely on where the ducts are located and how many leaks or how much damage they have. Ducts that are in the attic or crawl space and easily accessible can be resealed from the outside using either mastic or foil tape. This involves resealing all of the joints between each section and also patching up any holes. If any of the ducts are sagging or starting to come loose, the technician will also refasten and secure them to help prevent future leaks from developing.

For ducts that aren’t easily accessible, another option is to use a special airborne sealant. This method requires sealing up all of the vents and then turning on the blower so that it tries to circulate air through the ducts. With all of the vents sealed, the only place the air can flow is out through any gaps, cracks or holes in the ducts. The sealant is injected or sprayed in the duct system and the air flowing through the ducts carries it around the entire system.

As the air flows out through any leaks, the sealant sticks to the sides of the gaps or holes and continually builds up until they are fully sealed and no longer leaking. While this method is extremely effective and provides a long-lasting seal, it’s only suitable for sealing smaller leaks. For larger leaks, you will need to have them resealed from outside or the damaged sections replaced.

BENEFITS OF DUCT CLEANING AND SEALING

Both duct cleaning and sealing can make a major difference in how energy efficient your HVAC system is and how effectively it cools and heats. Sealing up leaky ductwork is especially important since air leaks lead to an HVAC system wasting lots of energy. In fact, a leaky ductwork system will often decrease the efficiency of an HVAC system by as much as 20-30%. If your ductwork has lots of leaks, it also increases the wear and tear on your HVAC system. It can also lead to it having a shorter lifespan or needing to be repaired more often. This is because the leaks result in the HVAC system taking much longer to cool or heat your home to the correct temperature each time it runs.

Duct cleaning provides major benefits both in terms of energy efficiency and indoor air quality. When a duct system is overly dirty, it results in lots of dust, pollen and other allergens getting spread around the house as the HVAC system runs. Dirty ductwork also attracts dust mites and allows them to thrive and can also lead to other pests like mice nesting inside the duct system. This last issue is why experts recommend professional duct cleaning after dealing with a mouse infestation. The reason is it’s highly likely that there will be lots of mouse droppings, nesting materials and potentially even dead mice inside the ducts.

The reason that duct cleaning is important for energy efficiency and allowing an HVAC system to work more effectively has to do with something known as static pressure. Static pressure refers to how much resistance the air flowing through the ducts meets. Ideally, the static pressure in your HVAC system will be as low as possible to allow the air to smoothly flow through the system.

If the ducts are dirty, all of the dust and debris essentially create barriers that increase resistance and prevent the blower from circulating air as easily. This air resistance or high static pressure results in less hot or cool air blowing out of all of the vents. This is so that the rate of heating or cooling is greatly decreased. It can also lead to the blower using more energy since it has to work harder to move air around the house.

THE PROFESSIONALS YOU CAN TRUST

Blue Best Plumbing, Heating, Air, Generators is a women-owned HVAC company with over 20 years of experience serving residents of Bountiful and the Wasatch Front area. Our certified technicians specialize in the full range of ductwork services and can easily take care of any issues with the ducts in your home. We also offer professional indoor air quality services and the full range of heating, air conditioning and plumbing services. If you need to get your ductwork inspected or require any other HVAC service, contact our team today.