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0:00
[Dan] What are the things that are different about this house? It is sealed in like a submarine door. Sets you up for 90% reduction in HVAC cost and heating and cooling costs. It can operate off the grid basically with the batteries and solar system. It also can survive climate change better than a standard home. [Bryce] I'm really excited today to be in New York to film the winner of the 2024 Department
0:21
of Energy's Housing Innovation Awards. Its energy efficiency rating, its HERS score, is -9. So it generates and stores significantly more electricity than it consumes, but its total costs were just 10% greater than a standard build would have been, and it's going to save upwards of $300,000 in energy costs over the first 30 years of its lifespan. Much of the lumber was reused from the drafty old 1930s house that stood before it. This is the future of home building, and we're
0:47
going to hear all about it from the mechanical engineer who conceptualized it and lives in it with his family. [Dan] Sustainable materials are a big part of of what we did here. Um, so all the wood that you're seeing is certified as sustainably sourced. It was interesting building this during the pandemic. Some flexibility on material selection was really important because some woods were hard to find or more expensive at the time. So we actually switched some woods. So
1:15
typically siding is cedar. A lot of siding that's done is cedar. This is actually hemlock. Hemlock was available in the state of New York. It was regionally sourced and it was actually less expensive than cedar at the time. Some guy upstate with a mill and a forest, you know, like that's where some of this stuff came from, including our flooring. [Bryce] You can you can see here, envelope. Is that the right term? How deep the envelope is? That's
1:40
one of the keys of Passive House, right? [Dan] So the walls have 12 inches thick of insulation cavity in them. Actually a little bit more than that, but the main insulation cavity is 12 in thick. So when we built the structure of the house, the structure of the house was actually even like pretty much where the window is and then the - what I call the puffy jacket of the house, which is the insulation jacket - is outside of that, and that's all natural materials. It's
2:06
cellulose. So it's like basically recycled paper that's treated for fire protection and mold protection. We built the modified Larsson trusses, those vertical members with recycled wood from the old home as well. Whatever we could reuse from the old home not only was like a sustainable thing to do but was also a cost effective thing to do and those things once in a while overlap which
2:26
is great, take advantage of that. More or less, a house is a house, you know. So like 'what are the things that are different about this house?' The windows and the doors is like the biggest cost difference. I mean, a big thing like we just talked about Larsson trusses and this insulation system and the air sealing of everything that takes exceptional skill and creativity from contractors that are experienced in doing that. There is a cost associated with that.
2:53
But there's also some cost savings. I mean, this house is so efficient that I don't really need a heating system here. Like heat pump system kind of heats this home pretty easily. So, here's the front door. One of the reasons we went with Vetta is this has like a nice architectural look. Vetta has these as a standard product. At the time, American companies did not have a lot of options on what you could order. This is an extremely efficient door. It seals very
3:21
well. Yeah, it's like a safe door kind of, you know, I mean, you you hear it when you open it and close it. Totally airtight. So yeah, there's only two passive house doors in the home , by design, because they're expensive. You know, you want to limit the number of doors and windows you have to buy. There's one here at the front door. There's one in the basement that goes to the garage. Those are the only passive house doors we bought. The only kind of exception
3:47
to that are the sliding glass doors, which are, you know, window doors as well. Because a lot of the year passive houses don't need mechanical heating and cooling. They can just operate with natural ventilation. One option in the milder days, even on a day like today, which is 75 out or something like that, you could open the sliding glass doors and open the turn window. It opens like this, widely open. Or if you want to just get
4:19
some ventilation, the handle turns up and it tilts just to provide a little bit of ventilation from the top. So, really versatile windows. When you close them and lock this, it is sealed in like a submarine door. There's no air coming in or out of that. There's no draftiness at all in the home. [Bryce] It's so impressive how much of the exterior space, especially in this beautiful big room, is glass. [Dan] That's right. [Bryce] It lets so much light in,
4:49
but because that porch sit sits out what 12 feet? [Dan] Yep. That's right, about. [Bryce] This is peak of the afternoon in the summer and the light isn't even close to the wall. [Dan] That's right. Yep. And that's that is the design. This is the design, right? The design is that the light will not reach the floor inside this room or even will not reach the house. So, I mean, this is actually a perfect example of how the solar orientation, solar design, shading really worked.
5:17
The glazing, the windows are really like currency. Any home, you want a lot of windows. You want you want to let light in. You want to be able to see outside. It's just nice for the atmosphere. And to meet the passive house standard, you need to meet certain energy, you know, criteria. So, you have to pick and choose where you're going to put windows in. And then maybe other parts of the house you're not going to put windows in because it would,
5:40
you know, be detrimental to the efficiency. So, this is a space where we want to use our window currency, right? [Bryce] That's right, because you're going to spend a lot of time in here. [Dan] That's right. And we can also get light in in the winter from the south. So, that's a that's a positive thing. Whereas on the north side of the house, you never want to have windows. I don't get any heating benefit from the north side of the house. [Bryce] You just lose it.
5:59
[Dan] There's no sun there - you just lose it - so, the north side of the house, when we walk to the back, you'll see there's no windows. There's the stairwell window, the big one, a bathroom window, and that's a bathroom window, and that's a bedroom. You know, it's like the minimum you could have. Passive house principal ideally has almost like a curve-shaped home facing south. We have an L-shaped home facing south. So, we're actually very close to the ideal here.
6:24
and that's the way the old house was. So, you know, when we were talking with our architect, Christina Griffin, at the very beginning talking about solar orientation, it kind of was like an epiphany like, oh, well, you're already oriented um perfectly for passive house. We'll just use that. This was the newest edition of the old home and this had like a masonry decent condition foundation to use.
6:45
The 1930s part of the home was here and was basically just like rocks stacked on top of each other for the foundation. There was no mortar left at that point. Oh my. So yeah, the uh the rest of the foundation had to go. But this was this was reusable. We reused it. We actually insulated inside this foundation. Typically when you're building passive house, you want to put insulation, if you're building a new foundation,
7:07
layers of insulation and then pour concrete or whatever your foundation is on top of that. We did the opposite here. Foundation was already there, so we insulated on top of it. Another thing to point out in the living room, sort of rare for a passive house, is the fireplace. [Bryce] I was wondering about that. [Dan] I know, everyone wants to know about the fireplace. So, this is a wood burning fireplace. Um, most people building passive houses will warn you
7:32
against putting a fireplace in a passive house. Um, and it was not easy to get this done. We love having a fireplace. We have to take a tree down on the property once in a while and we make firewood out of those trees and we can heat most of this home in the winter uh with this fireplace which is it's a relatively small fireplace actually. If we put a big one it would have been too much heat. But basically the fireplace is completely sealed off from the home.
8:00
So when you open it up it's like a regular fireplace. But when I close this there's no air exchange between the home and the fireplace. So most fireplaces, especially pretty much every fireplace made in in the US, sucks air from inside your house into the chamber for combustion because the wood needs oxygen to burn. This model, which is from Europe, is completely sealed off and only takes air from the outside.
8:26
It has a little duct that pulls air in from the outside. So it's you could even say that this fireplace is outside the house. [Bryce] It's an outdoor stove almost. [Dan] Exactly, it's a stove. We did a lot of research and we're basically looking for stoves like inset into the wall and that's what this is. [Bryce] Sweet. [Dan] Now, it does let air kind of circulate through it so that it provides heat to the house. So, it kind of sucks air in the bottom naturally and lets it come out the top.
8:52
This thing puts out a tremendous amount of heat. Um, it gets very hot in this room very quick when it when it's really cranking. [Bryce] I mean, here in the woods, in the beautiful winter time, you've got to have a nice cozy fire. [Dan] Yeah, for the ambiance. Yeah, we love it. We love having a fire. High ceilings was important to us. We actually had to lower the ceiling a little bit because of the 18inch thick roof.
9:14
So, how did we deal with that? Well, we had to lower the whole ceiling by 18 inches which meant the bottom of the roof, or the bottom of the ceiling rather, would come down extremely low on the sides. So, we cut it right here and created a light cove. It was sort of an adjustment that we made during design and construction that really kind of turned out well. Sometimes you have to get creative when things come up.
9:37
[Bryce] It's quiet. You don't hear... [Dan] Yeah, it's almost like you're in a different environment. It's like a real barrier from the outside world. It's like weird. It's a little odd. You know, like when you walk in on a really hot day, it's almost unsettling. [Bryce] You don't need to have the AC blasting, right? There's not this big contrast. It's comfortable. [Dan] Yep. It just stays at an even temperature. We actually have very little mechanical systems here for heating and cooling.
10:02
We have like a small heat pump system that takes care of the whole house. Just use as little as you can. That's the idea. That's what passive house is all about. Sets you up for a 90% reduction in HVAC costs--in heating and cooling costs. Because passive homes are so tightly constructed, they're basically airtight, you need to constantly ventilate the home. There's a air supply in each room.
10:24
there's a unit in the attic, which we'll look at, that takes air from the outside, filters it and supplies it through these to each room of the house. So each room of the house gets fresh air directly. And then the bathrooms and the kitchen exhaust air. And then we have an energy recovery ventilator in the attic which manages this. It has an exhaust fan, it has a supply fan, and then it has a heat exchanger
10:48
so that any of the air leaving the home we make sure to extract all the energy from it before it leaves the home. So in the winter we would be dumping room temperature air outside, wasting all that energy. Instead, it can transfer that energy to the air coming in, and it can do that very efficiently, 80-90%. And we really see that do a lot of work. I mean, when we change that MERV 13 filter on the fresh air intake, it's green.
11:16
Like, at the end of the spring, it's just covered in pollen. [Bryce] Wow. [Dan] And my nose is like, "thank you!" My lungs are like, "thank you, great job!" Resiliency from wildfire smoke. There's a lot of things that - even though it is a sustainable home - sort of beneficial to the fight against climate change, it also can survive climate change better than a standard home. Induction cooktop, highly recommend. Super energy efficient. [Bryce] And fast, right?
11:40
[Dan] You turn this thing on high with a pot of water and you like hear it bubbling instantly. It's really great. [Bryce] Is this a key to getting certified for the PHIUS? [Dan] It is in the sense that every appliance is built into the energy model. So when we are getting passive house certified, the 3D model of the home is input into an energy model, in the software called WUFI. And that calculates its energy performance.
12:04
In that model is everything. I mean, the air flow in each room, the outside air, all of the appliances and their efficiencies and energy consumption. If I pick a more high efficiency cooktop, you know, maybe I can add a window somewhere. You know, it's that kind of tradeoff. It's not prescriptive. You know, guidelines and codes that are prescriptive tell you exactly how to do something, which is great. It promotes safety and you know things are going to be built correctly, right?
12:29
But what it does is stifle creativity a lot in the design process. Performance-based design, in other words, the Passive House criteria says, "Save this much energy. This is the standard. Make it happen." You can get real creative about how you make it happen. So that's where the real like fun design stuff comes in. Of interest, we had a local artist create our our railing iron work here. He did a really cool job. This guy John that lives in the area.
12:55
The contractor did not want us to have a string hanging down to open the attic. And so he put this little loop in, but he needed to find something to hook it and he couldn't find anything. And he found this, which is actually intended for snake wrangling. To like pick a snake up off the ground, but it also works to to open the attic. [Bryce] I was actually looking at one of those on Amazon for getting disc golf discs out of trees.
13:21
[Dan] Perfect. So, we're up in the attic. You can see a few cool things up here. You can see the inside of our roof insulation layer. This again is an 18-in cavity of cellulose. You can see the blue taped marks. This is where the cellulose was blown in. [Bryce] You know what I noticed up here? It's not hot. [Dan] It's not hot. We're in an attic and it's not hot. So, this is part of the - we're inside the Passive House envelope. You know, the attic is inside the envelope,
13:48
which makes things a lot simpler. [Bryce] Meaning that this is cooled and heated... [Dan] This is cooled and heated just like the rest of the house. Like everything inside the Passive House envelope really should just be at the same temperature, conditioned all the time. If you think about it, like if you look at all these holes in the attic floor, if this was not part of the Passive House envelope, we would be punching holes all over the place through it. So, that wouldn't really work.
14:10
So yeah, that's a big part of like strategizing and and being being practical really. So when I was talking about the supply and exhaust air to each room, that's what these tubes do. And these tubes are run to those discs in the ceiling either for exhaust or supply. And they are supplying air or exhausting air all the time. And then in the back, they're all connected to the energy recovery ventilator, which is this.
14:37
So, this box has two fans in it. One is sucking air in from the outside and supplying fresh air to the house, filtered, MERV 13 filter. And then the other fan in here is an exhaust fan, which is sucking air from the bathrooms and the kitchen and dumping it outside. Yeah, we should talk about the team. So, our architect was Christina Griffin Architects out of Hastings. Christina's a Passive House expert, Passive House certified. She writes green energy codes. She's a genius. I love her.
15:07
She's an architect that's very much focused on energy efficiency and sustainability. She, herself, did all the energy modeling for this house. That's the kind of person that it takes to design this. Hopefully, into the future, Passive House construction can become more accessible because you do need to find someone who really understands it on the architectural side. Even maybe more importantly than the architect is the general contractor, the builder, needs to really know how to do it.
15:34
It's important from creativity of sourcing materials, the means and methods of building, cost effectively, the envelope and also the quality control of building the envelope and making sure it's airtight as it's going. Our contractor Ed Nugent, who tragically passed away, was a real legend in Passive House construction, I would say, especially after this project. was incredibly creative when it came to that. And on the quality control side, he had his guys
16:03
watching every nail that was put into this house and sealing it afterwards. It takes like that passion and creativity and diligence that not everyone has now. So there there is like a leap to get there. Even though the cost can be controlled, we've shown that-- we proved that this can be done cost effectively, but not everyone has a Christina and Ed to do it for them. So I think the most important thing we can do after this is like educate people on how to do it.
16:34
So this is--our Green Rater and LEED consultant was Integral Building and Design. I have to give them a shout out too. Tony Lisanti was our lead there. Tony handled our Passive House certification filing, our LEED Platinum tracking and filing, and also our Green Rating or HERS index, which was -9. Really impressive performance. Yeah. We started, wanted to be Net Zero. Learned about Passive House, wanted to do Passive House as our means to get to Net Zero.
17:05
Passive House requires some other certifications, including Indoor Air Plus. That's the air quality side of it. And then the federal government, the Department of Energy, still - as far as I know - has a program called the Net Zero Ready program. We got $4,000 in incentives to participate in the Net Zero Ready program with the Department of Energy. We won the award - the DOE award - through that program and that was a great experience.
17:33
So it was like all these sort of programs, guidelines, and codes sort of interact with each other and lead to each other. Yeah, cool. I'll show you some of the mechanicals down here. So this is our basement mechanical room. This is like the workhorse that does the most of the heating and cooling in the home. It's just a little air handler, you can barely hear it running and, you know, it's doing a lot of work right now.
17:55
[Bryce] You don't have a gas backup. You don't have anything--it's so well insulated that, in the depths of winter, you're not even batting an eye. Yeah. No, not at all. Yep. This is a very important piece of equipment. This is our heat pump water heater. It's a hybrid type. So, it has a heat pump unit on top. It has a traditional electric water heater in the bottom. So, the heat pump is the most efficient heating element.
18:19
The heat pump will run all the time. If it can't keep up it'll turn on the electric. It takes heat out of the air and puts it in the water. When it takes heat out of the air, it's air conditioning the air. So, the basement is air conditioned and dehumidified by the water heater. [Bryce] Oh, wow. [Dan] Super cool. Yeah. There is an air conditioner down here, but it never needs to do anything. When we talked
18:41
about reusing wood from the former house and diverting from the landfill, most of it you can't see because it's buried in the walls, but we did build this vanity out of the wood from the old house. The project manager under Ed Nugent, Ivy was her name. Ivy was a carpenter by trade and um was very passionate about it and built this herself and did an awesome job. [Bryce] That's one thing that surprised me is I was thinking there would have to be solar panels everywhere
19:10
and there aren't even solar panels on your garage. [Dan] Right. So, you can't really see them that well. They're only on the high roof. We have about 14 kW of solar capacity. We're probably putting out about 2/3 of that now. I checked earlier today. It's expandable. So, that solar system is designed to cover all of the energy consumption of the home itself. We also have an electric car here that charges.
19:31
So the electric car pushes us over our so solar production, but we set up the low roof to receive additional solar panels if at some point in the future we want to add them. Generally, when you're investing in a solar system for a home, you don't want to over-invest in it. You want to actually size it a little bit under what you're going to use so you're not wasting any money. These are the two solar inverters. They are connected each to a battery. These are LG Chem batteries.
19:57
Those two can back up the home for about a day or two. We've lost power here for multiple days, 3 or 4 days. The batteries have actually run out of power at night and we've waited until the sun came up and the solar system started charging them the next day and then we had power again. Sort of unlimited power as long as the sun comes up. [Bryce] You can see it out here, a lot of trees are falling on the power lines. [Dan] Exactly. We actually have a dead tree here now that
20:20
hopefully we're not going to be the next person to cause a power outage. But that's every that's everywhere here. On a day like today, in the summer, we always produce more than we consume. And we bank power with the utility that we can use in the winter. The old property had a lot of storm water runoff issues. You can't see it now. You could see it in the winter, but there's a lake down the hill over here
20:40
- our neighbor Linda's property - where there's a lot of, there was a lot of storm water runoff. So everything in terms of landscaping is designed for two things. One is to promote native plant species and try to eliminate invasives as much as possible. It's good for the ecosystem, promotes pollinators. That also ties into our non-existent neighbor, we call them, which is Teatown Land Reserves.
21:06
800 acres of land preserve and hiking trails. So, it's about being a good steward for the neighborhood. So, all of the storm water from the house itself is funneled down to this rain garden over here through underground drainage. [Bryce] Yeah, you can see there's no outflows. It flows... [Dan] Exactly, so all of these pipes that are taking storm water from the roofs, the garage, and the main house roof, come under the driveway. And feed water into this rain
21:33
garden over here. During a heavy rainstorm, we'll see the rain garden fill up with water a little bit, maybe 6 inches of water. And these are all native plant species that are designed to soak up lots of water. They're pretty pretty low maintenance. [Bryce] That's all you'll get is--this won't be a full pond, it'll just be 6 inches? Yeah, about 6 inches of water. This whole area gets pretty wet. And then that'll fill up and
21:56
that'll also overflow via a underground pipe under these rocks to our bioswale, which is down here. And a bioswale is basically another, like, trench dug in the ground with lots of flowers and plants that soak up lots of water. You'll just see different flowers blooming throughout the bioswale throughout the year. If you kind of look over here where the tall flowers are, that's a mature meadow area
22:23
that we've developed, and we're sort of expanding it to the rest of this. It takes a couple years, we've found, like maybe two years for that to really solidify itself and grow healthily and you're really getting like tall growth with flowers. [Bryce] It's starting to get there. [Dan] Yeah. Yeah. [Bryce] And it's a nice transition from the preserve. [Dan] Totally, yeah. It's such an active environment. And it's a little bit late in the day,
22:47
but if you're standing where we are at noon, like 11:00 to 1:00, you just hear bees everywhere. Like bzzzzzzzz... One of the strategies we implemented here was finding ways to make the home more architecturally interesting while keeping the Passive House envelope a very simple rectangle. So really, the design of the house - in its simplest form - is two rectangles: the big rectangle on the left and the little rectangle coming off the side.
23:15
So you'll notice that a lot of the things that are architecturally interesting are built outside of that sealed envelope or energy efficient envelope. The balcony at the master bedroom above the garage, the front porch is outside the envelope. The garage is completely outside the envelope. Those kinds of things are just meant to create, you know, introduce some curvature to the design. So, we're not just looking at a rectangular box.
23:40
You know, one of the goals was to show you can build a passive house, high efficiency home that does look interesting and make it cost effective. If we were to build curved walls and things that looked more interesting within the passive house envelope, our budget would have been blown pretty quickly doing that. Like the stone walls along the road, which you could see better from the road, are all built from stone harvested
24:03
from the site, as is the stone wall in front of the house. [Bryce] Oh, that's fantastic. Okay. So, so talk a little bit more about that. So, there was You bought the house. It was a 1930s... [Dan] Yep. [Bryce] Older. Was it about the same size or significantly smaller? [Dan] Uh, it was smaller, similar footprint, I guess you could say. The original house from the 1930s was a cottage, you would call it.
24:26
I think a one-bedroom home for a family of five people or something, you know, that lived there. [Bryce] Haha, "they all slept in one bedroom." [Dan] Yeah, it was amazing. And they put an addition on in the '60s. So, there was like a '60s addition with two more bedrooms. And then the owner before us did an addition about 25 years ago to put a living room on. So, it was sort of a hodgepodge of different construction, incredibly inefficient.
24:51
The whole house was like Swiss cheese to the outside. And yeah, we were able to divert 75% of that from the landfill. That included a lot of wood, so a lot of lumber from the old home. And I mean, from the 1930s, it was really amazing to pull the exterior wall um off the old house and see the wood from the 1930s looks like brand new. [Bryce] Really? [[Dan] Yeah. Slightly discolored, but like structurally sound. It's not used for the structure here.
25:18
It's used for nonstructural lumber. So, framing doors and things like that. And our goal was to just do the best we could on landfill diversion and we succeeded. Our contractor was excellent at that. I mean, it wasn't only the lumber, it was also--every window and door got reused somewhere. Someone used it. Appliances got reused. Like everything. We had a whole, we had like a pile out here of like stuff people could come take from the neighborhood and people would call me and
25:45
I'd say, "yeah, you need a stove? Great. Come on by." You know. [Bryce] So you tracked all that? [Dan] Yeah. Yeah, that was all tracked. I mean, some of the stuff was in really good shape, you know. The windows - even that were from the '60s - could still be reused. We reused sliding doors that were 30 years old, you know. I mean, a lot of stuff goes to the landfill that really doesn't need to.
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