Episode 70: The Invisible Energy Leak in Your Home (And How to Fix It)
The complete transcript for episode 70.
Molly Wood Voice-Over: Welcome to Everybody in the Pool, the podcast where we dive deep into the innovative solutions and the brilliant minds who are tackling the climate crisis head-on. I'm Molly Wood.
This week perhaps you, like me, are sitting in a house that’s leaking money and carbon emissions right out of the walls.
You know I love talking about buildings on the show because they are responsible for something like 40% of global carbon emissions, and about half of that comes just from heating and cooling.
But up to half of THAT energy is wasted. It just leaks away through badly sealed air ducts and building envelopes.
And while that SOUNDS like one of those boring infrastructure problems that’s too big to solve well. That’s the kind of stuff I absolutely love. And this is a climate solution that is definitely fixable and bonus you can do it in YOUR home and save money on your energy bills and make your inside air cleaner and healthier and more comfortable for everyone. Let’s go.
Amit
My name is Amit Gupta. I'm the CEO of AeroSeal. We are making buildings more efficient and improving the carbon footprint of the building. We make building efficient by sealing the leaks in the air ducts and building envelope.
Molly Wood
So how did, I mean, first of all, where did this idea come from and what convinced you that it would be a significant climate solution?
Amit
The original technology I was exposed to was my time at Carrier Corporation. This was a technology Carrier had acquired in 2001 and I was exposed to it in 2009 time frame.
And the idea was that carrier equipment can be installed with sealing the air ducts, which will make the overall efficiency of the system to be 25, 30 % better than the competition's overall system efficiency with the air duct sealing. Because in
Molly Wood
And what is, can I interject, what is Carrier for people who don't know?
Amit
Carrier is, I think it's one of the world's, it is the world's biggest HVAC company, air conditioner furnace company.
So when carrier install like a 90 % efficient furnace, the true efficiency of the furnace is actually significantly less because there are distribution losses. So the furnace is working at 90 % efficiency, but the air duct which is leaking 25 to 40 % is actually by the time the hot air gets to your room or to your house from the attic or from the crawl space where
these ducts are, it is losing that much of air. And not only the supply side of the air being lost, which is you're spending lots of money and heating or cooling, you're also sucking in the bad air from attic or from crawl space or between the walls because the return ducts are also leaking. And instead of getting air which is filtered and in your house coming back to the furnace to be reheated, you actually suck in 20, 30 % of the air
from the attic, which is not only much more expensive to heat or cool, because in the middle of the winter, the attic air is significantly cooler, but also it is filled with allergens, it is filled with humidity, so it has significant load on the HVAC system to make the air cleaner and dehumidify and then put it back into the house. Yeah.
Molly Wood
Fascinating, right. Okay, so Carrier then, as an HVAC company, is discovering that there's this inefficiency and started to develop this technology. Is that what you were telling me?
Amit
So Carrier acquired this technology from the inventor from...
in 2001, and this technology actually was originally developed with the funding of DOE and I think California Energy Commission at a national lab in California, Lawrence Berkeley National Laboratory. So Dr. Mark Madera, who was a staff scientist there, actually developed this technology and then licensed his own technology from the lab and developed the machine in his garage, another California garage story.
Molly Wood
We love our garage stories.
Amit
with and then within a couple years of that Carrier bought this technology but within Carrier it didn't really as much flourish and not just because Carrier was doing something wrong the technology was also not very ready at that time.
And carrier tried to work with the HVAC dealers to create a franchise franchise or relationship which probably didn't work as well early on and by the time technology got ready The whole business model was not really working very well within a large corporation
So in 2009 when I got introduced for it, I felt this technology has a worldwide application. Every building has ducts. Commercial buildings have ventilation ducts, supply ducts, residential homes, which is mostly US and Canada. I would say primarily have this ducts.
And these air ducts in our homes are leaking so much that US homes are losing like 540 trillion BTUs every year because of leaking air ducts. I mean, leaking air ducts is the single largest reason for energy wastage in US homes. Single largest reason, right? And nobody is fixing it.
Molly Wood
Wow.
That's bananas.
Molly Wood
Yep. Yeah.
Amit
I mean, we are focused on developing a higher efficient furnace, more efficient furnace. We are focused on making better heat pumps. We are focused on making higher efficiency air conditioners. But if you don't seal the air ducts, know, by making 10 % more efficient engine, if I compare it with a car, and your gas tank is leaking, how much more efficient car can you make?
Molly Wood
Right. Right.
Amit
Right, and that is what really got me excited. So I tried to see if this company could flourish within Carrier, but over time after, you this is 2009, 2010 timeframe with big financial crisis. With working with Dr. Mark Madera, we started the company outside Carrier.
Carrier had some on-outs which was part of the original deal so we took all of that and restructured it with Dr. Mark Madera and his partner and created a whole new company which we bootstrapped in 2010.
Molly Wood
Amazing. Could you help us translate all of those lost BTUs? are sort of, as we will discuss, a lot of good reasons why you would want to employ this technology. Let's start with the carbon emissions factor. I could you translate those lost BTUs into tons or gigatons for us?
Amit
Right.
Amit
Absolutely. So the way to think about it is that the buildings contribute 40 % of carbon emissions. The total emissions in the planet, 40 % is coming from the buildings.
Now, I'm using very rough numbers, so it is true for in certain parts of the world more so than the other parts of the world. But in ballparkish, are in the, you know, just to understand it and make it simple. 50 % of those carbon emissions are due to heating and cooling the buildings. So now we are at 20 % of all emissions.
And 50 % of that, which is now 10 % of those emissions, and certain parts of the world it could be 4%, certain parts of the world it could be a little bit more, is wasted due to leaks in the building. Leaks in air ducts and leaks in building envelope. I mean, this is enormously important for us to make good building envelopes and good building structures with good air ducts to make the buildings work.
really well, not only from the energy efficiency point of view, Molly, it is also the way we want the buildings to serve our purpose. The purpose of buildings and the controlled environment is a healthy environment, it's a comfortable environment, a productive environment. mean, we're going to homes just not to be there. We want to have good night's sleep, we want to raise kids, and all of that is very difficult,
subverted quite a bit if you don't have a good building envelope and a good air duct sealing.
Molly Wood
I'm going to ask you for one more definition, is building envelope.
Amit
Sure, so it is the shell of the building. It is the outside structure of the building. I mean, most people who live in the homes in a stormy day, as you were just talking about, the storm.
Molly Wood
having one in Oakland listeners, yep.
Amit
Yes, you would feel that the home becomes very drafty, right? You can see the air coming in, right? Or in California, it is obvious during the wildfire time that you get the smoke coming to the house. And if we have a right HVAC system and a good building envelope, that problem would be severely minimized.
Molly Wood
Yep.
Amit
because you can control the air coming into the home. It's not just seeping in from all parts of the home and it is coming from your filtration devices. You have a fresh air intake. You can control the humidity and the dust and the allergens and the smoke and that makes the house to be more comfortable, healthier and of course energy efficient.
Molly Wood
Right. I mean, that sounds amazing. And I think this is true of many, many people in California. We talk about our indoor, outdoor living. And what we mean is that the outdoors is always coming in. So talk about the technology specifically. You are focused pretty exclusively on ducts, it sounds like. And then, yeah. What do you do?
Amit
Yeah
Amit
Well, we started the company with AirDuck ceiling technology.
Subsequently, working closely with University of California, we have developed the technology to seal the whole building envelope or building shell. And we also have patents for sealing underground gas pipeline. So we have three technologies. And the gas pipeline technology is still under commercialization. We still have to put some work to actually take it to the market. But we have developed the air duct sealing and building envelope sealing and are rapidly deploying it in
the marketplace. The way audience can understand how our technologies work is imagine like a almost like a fixer flat for the building.
We pressurize the building by putting a big fan or air ducts with a fan and we inject like a very safe fog of a sealant material. It's like imagine a cigarette smoke being going into the duct work and wherever the leaks are as they try to escape the leaks, it makes a seal. So within...
less than an hour we can seal every leak in a home and currently we are doing it at scale in new construction application but we are also looking at doing the building envelope sealing at you know the homeowner change out or a tenant change out situations right because we have to it's like painting the whole house so you have to bring all the furniture in and cover it and that kind of thing for our material to just go to the leaks.
Molly Wood
Got it.
Amit
For AirDucks we do it and you can...
Molly Wood
That is, wait, I need you to back up. That is so sci-fi. So you just sort of blow this powdery smoke into all of the ducks in a home and it just collects in there and turns into a seal.
Amit
Yes, that is correct. It is not sticking to the walls. It is not going anywhere except where the leaks are. So in a home, we probably use a few ounces of material to seal up the whole duct work.
So that is the beauty of our technology, right? Yeah, so it is, I mean, people have called us Pixie Dust, people have said, you know, this is like a magic solution. It is basic physics. We have lots of controls and software built in to control the right environment, control the right pressures, humidity's, temperature. All of that is a very controlled way for us to doing it. But...
Molly Wood
is wild.
Amit
when people see it happening, it is very, very mesmerizing because on our computer screen, the homeowner could actually see, of a four ton system, I'm losing a ton of air.
And minute by minute they see on the computer screen, I'm sealing all my leaks. And by the end of the process, we print out a certificate for them to say, hey, you leaking a ton of air. Now you've saved 90 % of that. people can literally see in their bedrooms. So the best testimonial we get is, hey, the curtains in my bedrooms are moving now.
So that's the kind of thing they can immediately see the impact of sealing the air ducts.
Molly Wood
Right, right.
Molly Wood
Wow. And then talk to me about how it works for the building envelope and what are the parts of the envelope that need to get sealed? that like windows? Like what is, what goes wrong there?
Amit
So imagine everywhere there is a joint in the building, right? There is a leak. There's a potential for a leak. If you look at how the houses are constructed, if you put a wood frame to the concrete, there is supposed to be a felt gasket, right? And then that needs to be caulked so the air doesn't escape through that. And we have lots and lots of joints. Every time you're nailing a...
OSB board to the two by four and then you're making a façade. None of that is very airtight. You have to make it airtight by literally caulking miles and miles of all the joints in a home, which is very manual process.
Now, we have, again, made it very simple in the sense that we put a big fan on the front door after the windows are installed, and then we pressurize. I mean, it's like we put not like very high pressure, but we put like 100 pascals of pressure in the home.
And now the air is leaking out from all those crevices, right? We don't even have to find the leaks because the leaking air becomes our medium to seal the leaks. And then we put nozzle stations all around the home and it creates like a fog, as I said, like fumigation of a home, right? You see the house is filled with the fog. And again, back to the same software we have for building envelope where you see, I was losing 10 air.
air changes per hour, right? mean, air changes per hour is a measure for how much the house is leaky, which is a measure to say that under certain pressure, within an hour, 10 times the inside air would be exchanged from outside air. And that's a pretty normal starting point for us. And within an hour, we will bring it down to two air changes per hour, three air changes per hour. Anything lower than that would
Amit
require the house to have mechanical ventilation because you can't make the house airtight and not have fresh air coming in. So our motto is build it tight and ventilate right.
**MW VO:** Time for a quick break. When we come back, I’m going to geek out a little more on this crazy fog that floats around your house and seals cracks. Because geeking out … is what I do.
**MW VO:** Welcome back to Everybody in the Pool. We’re talking with Amit Gupta … the C-E-O of Aeroseal … about the nitty gritty of how YOU can get your leaky house fixed and keep that winter air where it belongs … outside.
Molly Wood
Tell me more about the basic physics part of it. I'm just going to be as clumsy as possible here because one, it's really fun to talk about pixie dust, and two, I think it will help people understand. Is it that the sealant is drawn to airflow? Because I assume it's lighter than air and it can kind of
Amit
You
Molly Wood
go where there's like suction happening from the badly sealed crack.
Amit
Yes. Yes.
That is exactly what you're describing. So the material gets airborne. It is not sticking to the wall, but it is as it's airborne, it requires the pressure differential through the leak. And if you can imagine like a pinprick on a balloon, right, air rushes out. It has significant velocity coming out of that small holes.
Molly Wood
Okay.
Amit
and that significant velocity takes the material and tries to force it out of that leak and in that process it makes the seal. It sticks to the edges and then it builds up very, very quickly. mean, if people Google on YouTube or in YouTube they search AeroSeal, this old house or AeroSeal, they can literally see the, I mean there are hundreds of videos out on YouTube too.
see exactly how it works. I real time they can see that the particle is coming and sticking and then slowly, within a minute, it just seals up the whole hole.
Molly Wood
What is it, not to give away too much of your secret sauce, but what is it made of?
Amit
It is a very, very safe material. It's a vinyl acetate polymer as a base material which is used in chewing gums and other safe materials. It does not have red list items which some of the places people look for. There's no off gassing. I mean, it's a very safe material. We have used it in hundreds of hospitals and they have a very strict, you know, review process of...
If people want to look up Energy Star and look up duck ceiling, you will find a very specific mention of aerosol sealant. We are probably the only aerosol-based sealant in California, Title 24 paperwork that is a special mention for it. So we've been around for 20-plus years and have done over 300,000 homes, have done...
Molly Wood
Yeah. Yep.
Amit
probably close to 10,000 commercial buildings, not only in US, Canada, but around the world. Many buildings, and we are in 34 different countries, so all over Europe, all over the Middle East. you know, our technology has been used in many of those special occasions where there is no other solution because once the building is built, to get to the leaks is...
Impossible, right? Imagine a commercial building where air ducts is behind a wall, behind a ceiling. There is nothing people can do.
Molly Wood
So it sounds like, you've alluded to this already, but let's put a finer point on it. It sounds like it's a tricky retrofit to do. Is that fair? Like if I'm a homeowner and I'm like my house is just leaky, would I call AeroSeal and say come in and fix it?
Amit
Yes, you would first call aerosol for the air duct sealing. So that you can. Yeah.
Molly Wood
Okay. And what is, I'm gonna back up even more. What's wrong with air ducts? Why are they so leaky? Is this just like a bad engineering situation or is it time?
Amit
This is.
This is how the certain construction practices are, right? Like we build a...
Molly Wood
Yeah.
Amit
air duct where we bend the sheet metal, make a joint and try to connect those joints. And there are hundreds and hundreds of those connections, right? There's a crimp which leaks, there's a re-join. We try to tape it and mastic it manually, but it is very difficult. Imagine an air duct which is sticking next to the wall or next to the ceiling. To get the access all around it is very difficult because it is very close to that
You can't put your hand around it for the manual way of properly sealing it. Some ducks, yeah.
Molly Wood
Okay, got it. So then, okay, so I have all these like messy, you know, and like they're screwed together and of course, Ayer's just doing whatever. So then I call you and what happens?
Amit
Right. And an HVAC dealer would come and he would attach our machine to your system and pressurize it, give you a report how much air duct is leaking. And then within a couple of hours, he would seal it and he would say, okay. And you would see a measurable difference in overall performance of your HVAC system and the comfort in the home.
Molly Wood
Yep. How much does it cost to have that done at the homeowner level? Generally, you know? Yeah.
Amit
It depends on lots of factors, but it could cost anywhere from at the low end, depending on the size of the home and other factors, low cost, high cost areas, et cetera, from $2,000, $1,800 to $3,000, $4,000. Now, some homes have multiple systems, so it could cost more. But, you know, generally, should see four-year, five-year payback.
Molly Wood
Mm-hmm.
Molly Wood
Right, well and that's what we should dig into. We should dig into that too because it sounds like it's not, mean it's not, we're talking about it as a climate solution, which it is, but it is also, as with many efficiency solutions, it saves you money. It's efficient, yeah.
Amit
I would also.
Amit
Absolutely, absolutely. So with 25C, tax credit.
homeowners can take 30 % of tax credit. that's what the prices I gave was before all the government incentives or benefits, right? So you can reduce 30 % cost right there. You can claim it from your tax credit, but you can also in many, many areas around the country, utilities gives 400, 500, $800 as an incentive for the homeowner to
get their air ducts sealed. Now, I would say if anybody in your audience is looking to clean the air ducts, right, which millions of homes get their air ducts cleaned because, you know, whether it's wildfire, whether they have pests, whatever be the reason, people want to get their air ducts cleaned.
I mean this is a perfect solution to clean the air ducts and seal the air ducts. And by the time you combine the solutions and the tax credits and the utility incentives.
I mean, it's a no-brainer for homeowners to do this. Absolutely no-brainer. In that particular case, I would say the payback could be less than two years. than, you know, so, you know. And again, most homeowners, Molly, do not do this for payback. Sure, they have consciousness around climate and they think the homes.
Amit
should become more efficient, absolutely. But they're doing this for the reasons of, my kid's bedroom is not hot, is not warm enough in winter and I'm putting a room heater there. My bedrooms are not getting enough air and I'm thinking of, you know, either, people use different kinds of, you know, like they're putting a window unit or a duct-free split, or they're trying to say, hey, my HVAC system is really not working because it's
and the symptom is because my home is not comfortable. And all that would get solved. In Florida, for example, people have humidity issues. We are not cooling the home as much as we are dehumidifying the homes. A 75 degrees with high humidity would feel very different than 75 degree in the home with low humidity, much different.
Molly Wood
Right. Right.
Molly Wood
Hmm.
Amit
It's all how you feel about it, right? Humidity plays a very important role. And all that is because of air ducts. So our large portion is because of air ducts. Because for humidity, if you're sucking in air from the attic, which is humid air coming back into the home, that creates the trouble, right, for us.
Molly Wood
Yeah. Huh.
Molly Wood
Right. It's so, just, I love these kinds of solutions where it's just the thing in the walls. And it's so, and it's so seemingly obvious, but impactful. So we've talked about the, the residential part of this, selfishly, cause you know, but I think, you know, consumers are out here wanting to know what they can do for themselves, but it sounds like there are some significant.
Amit
Hehehehehe
Amit
Of
Molly Wood
commercial building applications that are about all of the things you mentioned, but like you mentioned, hospitals. talk about that and kind of the benefits even above and beyond that go into like a specialized building like that.
Amit
Yeah.
Amit
Sure. So let's stay for even what we call commercial buildings. Let's stay with that for people who are living in high-rise or apartment buildings. Because they are homeowners.
But in most of the apartment buildings, there is a huge issue of odours where somebody's cooking something in their kitchen and everybody's smelling it, right? And especially in New York or Boston or in those kind of cities where these older building stock is just not ventilation, is not getting right ventilation. We can fix that because that is the kind of air duct as well which has to create that ventilation.
ventilation in a bathroom or a kitchen for the building to work really well. Or even in commercial buildings, there are bathrooms which does not get enough ventilation because of the air ducts which is leaking. And I these buildings have been built long times back and I don't even know at that time there was a method or there was a method to build the ductwork, but there was no way they were required to test for how much that ductwork
are leaking, it is the best effort work they were doing. So we can fix all of that. moving beyond that, I mean, if you're looking at these big buildings, you try to open the front door and you will see that it's like you have to put both your hand and you have to pry the door open because the building's ventilation is not working, because the building pressurization is not working.
So we fixed that also. And in hospitals and in universities, you know, these are the buildings which are getting significant amount of fresh air coming into the building because of contamination and infection. And if you're putting that much of fresh air, have to ventilate all of it out and you have to condition that air. And with commercial buildings, if the duct work is leaking,
Amit
The majority of the spend for commercial building in HVAC is because of the big fans they have, the fan energy which is required to push the air all around the building.
a significant part of the energy wastage. And with duct leakage, you can reduce the fan power and save significant amount of energy. In fact, we work with many escrows or energy services companies like JCI, Honeywell, and we are able to offer them in all of these types of buildings, like five-year payback for them to really make it very effective for them to
to provide that as a solution.
Molly Wood
Right. And then it sounds like, so Aeroseal is a business to business product ultimately, like it comes to you through installers, it sounds like.
Amit
Yes, mostly currently we are business to business. We encourage homeowners to come to our website, ask for our referral. We will direct it to the business to offer it for air duct sealing.
Envelope ceiling as I mentioned we are directly working with big builders like Beezer or Toll Brothers or Lennar in certain parts of the country. So we are rapidly expanding to become the standard way of building homes. I mean why should we build a home in 21st century which is leaking like a sieve? I mean it just makes it makes no sense to do it.
Molly Wood
And the envelope part is the part that you wouldn't necessarily do that as a homeowner. That's the one where you wouldn't do it while you're still in there. It would be in between as part of a sale or when you're moving, something like that. OK. Got it.
Amit
That is correct. That's what we're doing.
Amit
Yes, that is correct.
That is correct. That's where we are focusing on. We have done some work when people are really doing a re-gut or rehab or very high-end homes like, we want to get, we don't have a comfortable home without all this, you know, like in California and other places, some very high-end homes. People have made the effort where we have done the work even when people are living in the home, but with all the extra effort to prep the home to do it.
Molly Wood
Yep. And then.
Amit
It's expensive to do it in existing home comparatively and hard to scale for us. So that's why we're not putting lots of energy behind it.
Molly Wood
Yeah, I could imagine. Okay.
Molly Wood
Right. and what is the, what's the, if we're losing 40%, let's say, of energy from the air ducts, what's the, how much are we losing from the envelope?
Amit
So air ducts are leaking around 25 to 40 % as per DO, Department of Energy study. Envelope, it depends again on when it was constructed and what building code they have adhered to. If the building code is...
Molly Wood
Yep.
Amit
The newer building code in some areas require five air changes per hour, which is also quite a bit because five air changes is you're talking every 12 minutes the air could infiltrate every hour, every 12 minutes. That just is quite a bit of leakage in my mind. We should easily bring it half of that and make it much, much more comfortable home.
Molly Wood
Hmm.
Yeah. Yeah.
Molly Wood
And then in our remaining time, tell me about the third product that you're commercializing right now.
Amit
So underground gas pipeline is where we have proven it in the lab and we have the patents around the world for that technology, but we have not put our engineering resources to commercialize it because it's a more, it's a little bit tougher engineering problem for us to solve. And hopefully in 2025, we'll start putting our engineering resources to commercialize it in the coming year.
Molly Wood
Mm-hmm.
Molly Wood
Mm-hmm.
Molly Wood
And the idea is to obviously stop underground gas leaks, which is a huge deal. Yeah.
Amit
Yes, so methane is a huge deal, right? It is up to 80 times far worse than CO2. So that's an application. And these old infrastructure of pipes underground, they have small leaks. And it is very, very difficult to seal them because you have to dig up the road, you have to dig up the ground. I mean, it might take
millions of dollars to actually fix all this and so it's not being attended to unless it becomes catastrophic or it becomes really a safety issue. So we can fix that and that could have an enormous climate impact. Now we can take this technology also in an industrial application and fix the leaks in compressed air system because there are
miles of compressed air, these pipes are running and they're also leaking and it's wasting energy.
Molly Wood
Right. It's in the walls, people. The leakage is coming from inside the house. Tell us where people can find arrow seal.
Amit
[aeroseal.com](http://aeroseal.com/) a-e-r-o-s-e-a-l dot com
Molly Wood
Love it. It's so simple and yet so magical. Thank you so much for the time. I appreciate it.
Amit
Thank
I appreciate the time, it was such a pleasure to talk to you.
Molly Wood Voice-Over:
That's it for this episode of Everybody in the Pool. Thank you so much for listening remember that climate action is made up of so many things you might not even be thinking about but the goal in SO MANY of the solutions out there is that we live a BETTER LIFE while we’re doing right by the planet and every person and animal and plant on earth.
Win win win.
Please email me your thoughts and suggestions to in at everybody in the pool dot com and find all the latest episodes and more at everybody in the pool dot com, the website. Because together we can get this done.
See you next week.