Burying Ducts In Attic Insulation: Pros And Cons

Should ductwork in an attic be insulated?

Besides the cost, there’s no practical reason to leave attic ducts uninsulated. The cost of undertaking such a project will eventually pay for itself in monthly energy savings. This is especially true when air ducts are located in unconditioned areas like the attic.

Should I wrap my ductwork with insulation?

Once you’ve ruled out mechanical or other HVAC issues, consider insulating your metal ductwork. Uninsulated or poorly insulated metal ducts are often the culprit. Insulation prevents warm air outside the ducts from contacting cool, metal ductwork, thereby preventing condensation.

Can insulation touch air ducts?

Batt insulation – For an affordable solution, foil-backed fiberglass or cotton batt insulation can be cut to size, fit around your ducts and taped into place. Foil-backed self-adhesive foam – This type works especially well for irregularly shaped ducts. Simply wrap it around the ducts and press it into place.

Can you put blown in insulation over ductwork?

If the ducts must be located within a vented attic, one option for protecting the ducts and helping to minimize heat transfer between ducts and the unconditioned attic is to lay the ducts on the attic floor and cover them with the same blown insulation that is used to cover the attic floor.

Should an attic be fully insulated?

As a cold space, its purpose is to provide proper air ventilation from the outdoors while preventing air from leaking from heated living spaces. If you don’t insulate your unfinished attic, you’ll face heat loss, higher electrical bills and may even face ice damming and water damage in colder climates.

Why is it not a good idea to run ductwork through attic spaces?

At its most basic, the temperature gradient between the air inside and outside the ductwork is reduced, which reduces the amount of energy lost through the sleeve of the ductwork. Research has shown that ductwork installed in unconditioned attics or crawl spaces can waste 20% of the system’s energy output.

What happens if ducts are not insulated?

In Unconditioned Areas: Ducts in unconditioned areas like basements, ceiling spaces, and other locations should be insulated to avoid condensation that can increase humidity and allow mold growth. Insulation can also block noise from ducts and other parts of your home.

Does exposed ductwork need to be insulated?

Exposed ductwork must have minimum insulation installed.

What is the best duct insulation to prevent condensation?

If your ductwork lacks an insulation , you better insulate it before summer starts and you start experiencing condensation issues. To properly insulate your ductwork, use metallic foil duct tape. By doing this, warm air won’t reach the cold surfaces of the ductwork.

Can you double wrap duct insulation?

Double layer duct wrap insulation: Installers could use one layer of unfaced duct wrap to achieve an R-10, and then add a second layer of faced, 3” R-8 duct wrap.

How do you secure insulation to ductwork?

Insulation is securely attached to the ducts with metal wire or rot-proof nylon twine. Pattern of wire or twine is sufficient to securely hold the duct insulation tight to the duct.

Does insulating ductwork reduce noise?

Lining the interior of your ductwork adds valuable insulation to make the system more efficient while dampening sound to keep it quieter.

Should I insulate my ductwork in the attic?

Running unprotected ductwork through an attic can court problems. Particularly in hot-humid climates, moisture can collect on the outside of ducts in summer. Encapsulating ducts in closed-cell foam or following code-prescribed methods for burying ducts in insulation can prevent the problem.

How to seal air ducts in an attic?

Steps To Sealing Attic Air Ducts Use zip ties to secure any loose ducts to the attic floor. Apply a generous amount of sealant mastic over the thermal leak. Make sure the duct is secure in place and wait for it to dry. Once the mastic has dried, the thermal leak should be eliminated.

What is the R value of attic duct insulation?

Summarizing: 3” or larger supply and return ducts in attics must be insulated to a minimum R-8. Ducts smaller than 3” in attics must be insulated to R-6.

Where should you not put insulation in the attic?

Also, when laying down additional insulation, work from the perimeter toward the attic opening. Never lay insulation over recessed light fixtures or soffit vents.

What are the disadvantages of attic insulation?

One drawback is the amount of space each layer of insulation takes up. Their low R-value means you might need a foot of insulation to protect your home, so you have less usable space. They also cause skin irritation for people who are exposed during installation and inhaling fibers may increase cancer risk.

What happens if you have too much insulation in your attic?

It is possible to over-insulate your house so much that it can’t breathe. The whole point of home insulation is to tightly seal your home’s interior. But if it becomes too tightly sealed with too many layers of insulation, moisture can get trapped inside those layers. That’s when mold starts to grow.

How long does ductwork last in attic?

The estimates on how much air is lost due to ductwork issues vary (they range anywhere from 25% to 50%). That means you’re probably wasting energy and money. On average, most ducts last up to 15 years. By then, materials such as plastic and fiberglass start to break down, and ducts tend to be damaged more easily.

How to insulate an attic with a HVAC system in it?

You can wrap fiberglass insulation around your ductwork. Use a square and utility knife to cut the sheets to size so they fit around the duct without needing compression. Use metallic foil duct tape recommended by attic insulation professionals to seal the insulation and hold it in place.

What is the disadvantage in having ducts in the ceiling?

Typically the biggest disadvantage is just how how or cold the attic gets. There will be considerable pressure against the insulation any time the space surrounding the duct is a significantly different than the air inside the duct. That will make proper insulation even more important.

Can you insulate existing ductwork?

If you decide to insulate your old ducts, just make sure you or your contractor follows this order of operations: Seal the leaks with mastic or mastic tape (we follow a highly precise “seal and test” protocol that identifies all leaky areas and results in 4% duct leakage or less).

How to tell if ducts are insulated?

In addition, before applying air duct insulation, check the ductwork for the presence of an insulated lining (installed during its fabrication process) by removing the filter from the furnace’s filter box and shining a flashlight inside the ducts. Bare metal indicates uninsulated ducts.

What temperature are ducts insulated at?

HVAC systems typically operate with internal air temperatures between 40˚F (4˚C) and 250˚F (121˚C). Systems operating outside this range are not considered in this guide, except that fibrous glass insulation boards may be used in systems operating at internal air temperatures between 0˚F (-18˚C) and 450˚F (232˚C).

Does return duct in attic need to be insulated?

Supply ducts in an unconditioned attic must have insulation equal to or greater than R-6. All other supply ducts and all return ducts in unconditioned spaces must have insulation equal to or greater than R-6.

What is the best insulation for ductwork?

Flexible rolls of fiberglass are especially well-suited for attics, where their pliable shapes can be easily contorted around complex ductwork. Polyethylene – Compared to fiberglass, polyethylene insulation is more expensive. That said, polyethylene is suited to outdoor ductwork as it’s made to withstand the elements.

Is insulating ductwork worth it?

Ducts are made of sheet metal, fiberglass, or other materials. Ducts that leak heated air into unheated spaces can add hundreds of dollars a year to your heating and cooling bills, but you can reduce that loss by sealing and insulating your ducts. Insulating ducts in unconditioned spaces is usually very cost-effective.

Should I insulate my air handler in the attic?

Should I Insulate Air Handling Systems? Absolutely! Traditionally, organizations such as the Insulation Institute recommend insulating air handler ducts with fiberglass insulation solutions such as duct liner, duct wrap, or fiberglass boards.

Does ductwork need to be insulated in conditioned space?

Transfer grilles from bedrooms, combined with central returns, simplify the process of bringing ducts into conditioned space. Placing ducts in conditioned space eliminates the need to insulate ductwork, but it does not eliminate the need for good duct sealing practices.

How to seal air ducts in an attic?

Steps To Sealing Attic Air Ducts Use zip ties to secure any loose ducts to the attic floor. Apply a generous amount of sealant mastic over the thermal leak. Make sure the duct is secure in place and wait for it to dry. Once the mastic has dried, the thermal leak should be eliminated.

Does attic insulation affect air conditioning?

Attic insulation reduces your AC unit’s energy usage, making it more cost-effective to cool your home during the summer. Hot upper floor: If you have a multi-story home, you may notice that the second floor is always hotter than the ground floor.

Can You Bury ducts in attic insulation in a humid climate?

Should you bury ducts in cellulose or fiberglass insulation?

Can You Bury ducts in a humid climate?

Can you put duct insulation in a blown attic?