How to Cover Round Air Ducts With Insulation

Does Ductwork Must Be Insulated?

When speaking about ‘ductwork’, we’re referring to the system of pipes and ducts that flow into cooled or heated air all through the home.

Sadly, absolutely the majority of ducts are made out of skinny materials (fiberglass or sheet steel) and that’s why the air that’s touring by the system can simply get misplaced. 

After all, you may at all times select to not insulate the ductwork in your house. However including insulation to the system has fairly a couple of advantages that you need to find out about:

  • Decreased vitality consumption ; decrease electrical energy payments

Insulation helps make sure that the air that’s touring by the system stays on the desired temperature. Furthermore, it prevents leakage which, in its flip, results in vitality loss.

In truth, with out correct insulation, you could be shedding as much as 30% of the vitality that’s used to warmth or cool your home.

Tip: to search out out in case your ductwork wants further insulation, place your hand near the availability register. The reply is ‘sure’, in case the air feels lukewarm.

  • No condensation

Each time cool air passes by a really heat a part of your home, it could trigger condensation to seem within the ductwork. Because of this, there will probably be moisture build-up that may result in mildew and mold development, and different issues.

Excessive-quality insulation can stop condensation from occurring within the system.

In a nutshell, ductwork insulation will assist make sure that your house stays cozy and at an optimum temperature. And all that – with out the cooling and heating programs having to work at full capability on a regular basis. 

However does all ductwork must be insulated? Or are there sure areas the place insulation is extra needed?


Depend on Trusted Professionals

Though it is likely to be tempting to try to avoid wasting cash by insulating the ducts in your house by your self, that is truly a job that’s greatest left to professionals.

For one, climbing into an attic and attending to the ducts which might be positioned in ceilings, basements, crawlspaces and different out-of-the-way areas in your house takes a variety of bodily effort and generally is a soiled course of. It is also essential to keep away from dislodging ductwork or in any other case inflicting holes or tears within the course of.

Professionals additionally know that it is a good suggestion to insulate your basement partitions on the similar time you insulate the ductwork within the basement, since insulated ducts will give off much less waste warmth that previously was serving to to maintain pipes from bursting as a consequence of extreme chilly in the course of the winter.

For higher peace of thoughts, you may rent trusted HVAC professionals to maintain the job and do it proper the primary time, on time and for value that is smart in your funds.

Extra Studying

To study extra about making certain energy-efficient properties, learn these nice articles from HVAC Seer:

Step by Step Directions

Whereas it isn’t insulating your ductwork, taping joints in ducts ought to be carried out first.

Beneath are the mandatory steps wanted to correctly set up the insulation round your ductwork in your attic, basement, and/or crawl house.

Step 1: Select what sort of insulation you wish to use for the job.  Probably the most cost-effective sort is foil-backed batts.  You get extra in your cash, however there are different choices that had been mentioned earlier on this article. So long as it’s warmth resistant and has an R-factor better than 3.5, it’s a first rate possibility for the insulation of your ductwork.

Step 2:  Clean ductwork by wiping it down.

Step 2:  Clear ductwork by wiping it down.

Step 3: Measure the world of ductwork you’ll be insulating, after which reduce your heat-resistant insulation to the right measurement. “Measure twice, and reduce as soon as,” because the saying goes.  You don’t need to have to make use of extra items than needed.

Step 4: Wrap the ductwork with the properly sized

Step 4: Wrap the ductwork with the correctly sized insulation. Be sure that it suits tightly across the ductwork, however don’t compress or dent the ductwork, as a result of compressed fiberglass insulation doesn’t have as a lot air throughout the materials – and air pockets assist maintain in warmth. Additionally, guarantee that the foil is on the skin with the fiberglass insulation on the ductwork.

Step 5: Use duct tape to safe the insulation across the ductwork.  Do that by merely wrapping the duct tape across the insulation and the ductwork.

Step 6: Using your foil tape, completely seal the

Step 6: Utilizing your foil tape, utterly seal the seams of the insulation through the use of one lengthy piece of foil tape alongside the complete size of the seam.

Step 7: If there are any areas that you cannot fit

Step 7: If there are any areas that you just can not match and seal the insulation across the ductwork, you should utilize mastic to seal the world by way of a caulking gun and a tube of mastic. Use a instrument on the mastic to power it in opposition to the seam to get the very best seal.

Step 8: Repeat the steps above on every section of

Step 8: Repeat the steps above on each part of ductwork.

Step 9: Double verify all of your ductwork to make sure that all the things is correctly coated, insulated, and there are usually not any uncovered areas the place heated or cooled air can escape by way of uninsulated ductwork.

These steps described how you can use versatile, foil backed insulation to wrap your ductwork in your basement, crawlspace, or attic.  You should use the identical fundamental steps when putting in inflexible insulation, too.  Slightly than wrapping the insulation across the ductwork, you’ll reduce the inflexible insulation to suit across the ductwork after which use the foil backed duct tape to seal all of it collectively.

2. Collect Obligatory Supplies

Now, head to the ironmongery store or on-line to order your entire supplies. You’ll need each foil-faced duct insulation (R-6 or higher) and particular high-temperature foil tape designed for duct purposes.

Click here for foil duct tape from Amazon.

If air sealing is required, use the identical foil tape for the joints that you just use for the fiberglass insulation. If the air leaks are significantly dangerous, you may couple the usage of the tape with the usage of specialised duct sealing mastic.

Click here for a utility knife from Amazon.

The best possibility to chop the fiberglass batts is to make use of a utility knife. If wanted, seize one in all these whereas purchasing for the remainder of the supplies.

How a lot duct insulation do I want?

For fiberglass batts, calculate the overall space of the skin of your ducts utilizing geometry and the measurements you took throughout your inspection. Watch out when changing between ft, inches, and different models.

If your ducts are round, use the circumference of

In case your ducts are spherical, use the circumference of a circle occasions the overall size to get the overall sq. footage wanted. The letter ‘r’ within the following equation stands for the radius, which is the space from the middle of the circle to the sting. The circumference equation is as follows:

Circumference = 2πr

You may simply add up the perimeter for sq. or rectangular ducts with measurements taken with a ruler or tape measure. Then, multiply the perimeter by the overall size of ducting to get the wanted sq. footage.

Typically, purchase at the least 10-percent extra of the fabric than you calculate for the sq. footage as corners and troublesome areas usually take extra materials than you hope. For the tape, calculate utilizing your measurements and purchase further rolls that are returnable if left unopened.

Steps for Insulating HVAC Ductwork

  1. Test the velocity of the blower motor on the furnace. If needed, change the wires to cut back the blower to its lowest velocity.
  2. Press a steady strip of foil tape to all longitudinal seams alongside straight runs of duct.
  3. Use a paintbrush to use duct mastic to the joints the place an elbow connects to a duct.
  4. Use a utility knife to chop foil-faced fiberglass insulation to the right measurement.
  5. Wrap the insulation across the duct, after which pinch the seam closed. Safe the insulation with brief strips of foil tape.
  6. Apply an extended strip of foil tape alongside the seam within the insulation. Repeat to insulate the remaining ducts.
  7. To put in preformed duct insulation, begin by disconnecting an elbow to reveal the tip of the duct.
  8. Snap a plastic cap onto the duct finish, then slip the preformed insulation over the duct.
  9. Gently pull the insulation over the complete size of duct.

So, which is it? Insulate or change?

It is as much as you, but it surely’s typically more economical to replace the ducts. By the point you pay for supplies and labor for sealing and insulating current ducts, it’ll often shake out to a value that is near what it prices to get new ones.

In case your contractor does issues the best way we do, alternative additionally leads to a greater duct system that retains you extra snug and maximizes effectivity.

With us, you get a model new duct design that’s precisely sized in your residence and your HVAC system. Valuable few HVAC contractors will do that. Most are “field swappers” who simply change what you may have with the identical precise factor. In different phrases, the system will nonetheless underperform – even after the ducts are insulated!

Within the occasion you are already replacing your HVAC system, that is a good time to additionally change your outdated ducts. The brand new duct system will reduce vitality loss and, assuming it is put in by a educated firm, will provide higher high quality and luxury in comparison with no matter you’ve got received now. It is going to additionally pair properly along with your new HVAC tools. Your current ducts, then again, won’t.

Why Ought to You Insulate Your Ductwork?

We talked about vitality effectivity by decreasing vitality loss by uninsulated ductwork when heating and air con your house. Ecofriendliness shouldn’t be ignored. The extra vitality that’s conserved or saved, the higher it’s for the atmosphere.

Plus, the actual fact your tools gained’t work as arduous to maintain your house snug.

It’s additionally true that in case your HVAC system is correctly sized however you’re shedding a variety of the handled air with uninsulated and probably leaky ductwork, your furnace, warmth pump or AC won’t be capable to sustain, and components of your house gained’t be adequately heated or cooled.

OK, we’re all on the identical web page now. Let’s discuss how you can insulate ductwork within the basement or attic.

Ducts that Run Beneath Joists

In case your spherical air ducts run under the joists, lay one insulation batt on high of the duct. Direct your helper to carry a second batt as much as the underside of the duct. Wrap the twine snugly across the duct to carry the highest and backside insulation batts in place. Direct your helper to carry up the underside batt simply forward of the place you’re wrapping the twine across the duct. Tie knots to safe the ends of the twine.

Insulating your ducts

Including insulation to your ducts is not so simple as getting some duct wrap and taping it collectively. Okay, some folks and contractors do insulate their ducts this fashion. And technically, the ducts are insulated afterward.

However in the event you go this route, you are forgetting one thing tremendous essential: duct leaks.

Duct leaks are the scourge of vitality effectivity and indoor air high quality. Gaps, cracks, holes, rusted out corners… When air leaks by your ducts, it brings contaminants into your indoor air and reduces the effectivity of your HVAC system. By not addressing duct leaks, you are actually polluting your clear, filtered, conditioned air with soiled, unfiltered, unconditioned air!

Bear in mind, a variety of your ductwork is both in your crawlspace or your attic. Do you actually need to be respiratory the air from these areas 24/7?

Anyway, the purpose of all that is to focus on the truth that you have to seal the leaks earlier than you insulate the ducts.

Insulation blocks the motion of warmth, however it could actually’t stop air leaks. Soiled air will nonetheless enter your ductwork by the leaks, even after you add insulation. In case you resolve to insulate your outdated ducts, simply ensure you or your contractor follows this order of operations:

  1. Seal the leaks with mastic or mastic tape (we observe a extremely exact “seal and check” protocol that identifies all leaky areas and leads to 4% duct leakage or less).
  2. Wrap fiberglass duct insulation across the ducts and tape the seams collectively.

After all, you may additionally contemplate…

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