 Good morning everyone. My name is Ellen Vaughn and I head up EESI's buildings work. We promote policies and practices to make our building sector more sustainable and resilient. I have the honor this morning of introducing and moderating our two buildings panels and the reason we have two buildings panels, first of all we're delighted to have you all here and thank you for exhibiting and talking about the building sector because the building sector for those of you who might not know consumes about 40% of our energy. Nearly 75% of our electricity and is responsible for about 40% of greenhouse gas emissions. So it's a significant part of the economy as well as a contributor to to our energy and environmental issues. The good news is that buildings are becoming much more sustainable and resilient that is they're using less energy less and more renewable energy consuming fewer natural resources for construction and operation and providing greater comfort safety durability and functionality for the occupants and that's because of a combination of factors we have it's all of the things coming together it's R&D government and industry innovation consumer knowledge and demand codes and standards financing public policies and training of building professionals architects engineers and builders it's all those things that are that are necessary and on our panel we have it's really the individuals who are leading the way that we have most to thank for this and we have some of the leaders in this space on our panel so I am delighted to first start with a home builder who has made it a priority to build homes that use fewer natural resources and at the same time are awesome for the people who buy them and live there so thank you for being here care care de grande jamb I want to always say it in the French way with high-performance homes welcome and come on up again thank you very much this is my third year in a row and I look forward to every year this is such a powerful environment the best minds the best people out here so just to give you a little bit of background my name is care care de grande jamb I'm a home builder I build in Pennsylvania and in Maryland I've been building for 30 years but I started doing the zero energy net zero stuff about 10 years ago and that's when I got the shot in the arm like a resurgence so we at high-performance home have dedicated ourselves to building at a zero energy level which means the house has the ability to produce more electricity than it consumes now I am here as a guest of NGBS because this was probably the reason why I put the formula together through the the workings of their research center so about NGBS now the National Green Building Standard which is the NGBS it's a certification that goes well beyond saying a home is energy efficient it provides independent third-party verification that a home or they also do multi-purpose dwellings apartment buildings land development is designed and built to achieve high performance in the six key areas that they hit it's site design resource efficiency water efficiency energy efficiency indoor environmental quality or indoor air quality and building operation maintenance simply put creates a better higher quality place to call your home so as a home builder we hit all six of these these key areas are vital to creating the home that can withstand the test of time while delivering one of the healthiest living environments with the smallest carbon footprint possible in order to meet the requirements of these six categories we build a home differently from start to finish we plan different we use unique products and renewable energies and we certify all of our homes through a third party to ensure that not only the meeting these requirements but they're exceeding them we build with a methodology that we try to build a house like a refrigerator and once you close the refrigerator door it doesn't require an awful lot of energy in order for it to maintain to that level so we use a superior wall which we can go into more later if you want to ask outside so superior wars it is a cast off site not a port in place concrete has a built-in R 21.3 and then I go up from there and I use a sip panel sip panel is a structurally insulated panel system it's solid EPS gives me close to an R 30 so if I'm doing an R 21 and R 30 then I spray foam slash blow in my insulation to the attic I'm getting R 50 so as you can see it's a very well insulated product it's also very very tight I want to get down to a one-air exchange per hour which is where my energy modeling fits the best I believe that in Maryland it is three air exchanges per hour so we're exceeding those codes but home innovation laboratories certifies that the homes meet the requirements of the national green building standard which is only the residential green building rating system that is approved by ANSI as an American national standard and GBS provides practices for the design and construction of all types of green residential buildings renovations and land developments they're stringent third-party verifier there they are stringent third-party verified certification program ensures that the homes and apartments are built in compliance with NGBS and focuses on three primary attributes that are highly marketable in today's discerning customers healthy homes they provide fresh air and air ventilation that improves the indoor air quality limiting the pollutants and the contaminants in the home preventing the moisture problems that can contribute to the mold and attract the pest we do this through a series of techniques when we seal the home much will be possibly can but when we do that you have to have a makeup there which Zender is going to speak on it more intelligently than I am and I either use an ERV or an HRV energy recovery ventilator or now I have a Panasonic fan system which and doesn't give me the humidity control within itself but it does it within holistically for the environment of the house so we try to do the lower operating costs reducing the utility costs to a cost-effective energy and water efficiency practices controlling and maintenance costs through durable construction and product selection we provide technical and educational resources to ensure the home's optimum performance we have the home help itself we give you a very nice well-managed thumb drive that gives all of your warranties know your critical information that way you can help the house help itself and it just makes for a better home by building a home with well-insulated and sealing materials far beyond code including newest and most efficient appliances and fixtures incorporating free hot water systems and recirculator pumps for hot water distribution using low to no maintenance materials and equipping our homes with the manuals we just spoke about able to build houses that have little to no energy supply cost one of the things NGBS also wants to ensure is a lifestyle promoting walkability reducing the home maintenance through enhanced durability preserving the natural resources through responsible land development practices the beauty in third-party verifications and certifications the homeowner is obvious but not only being told by the builder but your home is at the top of the performing by national certifying bodies like the home innovation and providing the assurance of it the third-party verifiers extra set of eyes each homeowner's project it's brought to brought into confirmed green practices when not only specified and planned but executed properly if not it doesn't get certified it's quite that simple as the ANSI approved standard the NGBS is also required to undergo regular updates by public conscious process this ensures the standard is ever-evolving and evolving and improving to keep pace with best practices and building technologies local baseline codes can be somewhat stagnant for example in Pennsylvania I'm building to a 2009 IECC energy code however the NGBS requires a much higher level of efficiency to benefit both consumer and the environment I'm very interested to see how the smart home technology advancements will continue to play into categories like healthy home lower operating cost and sustainability currently we're working with IBM Watson IoT technology to create a package of smart home innovation that will drastically improve these categories and more thank you so much care we wish all builders had that enthusiasm for building green you alluded to best practices and I am delighted to now introduce our next speaker Catrine Klingenberg is executive director of passive house Institute US and passive house as many of you might have heard is all about really reducing that energy load and getting the house as efficient as possible and Catrine will tell you all the good details about that thank you Ellen I'm not sure I have enough time for all the good details it's definitely very very exciting concept that I have the pleasure to tell you about today I'm the executive director of the passive house Institute US and there are a lot of really really good reasons to design buildings to very low loads as Ellen mentioned and our mission is a non-profit is to transform the market and to make these strategies and practices best practices in the United States so what what are the reasons to design buildings that are very low load so for one of course the energy consumption we we bring that one down cost effectiveness of utilities that you have to pay for your building under operation but they are a whole bunch of other really good reasons why you want to go to these low load homes and some that are very popular of course are the increase of comfort in the home you have no drafts you have very comfortable surfaces if you insulate your building really well you have a very good indoor air quality because if you build your building very tight what you also need is good filtration and dedicated filtration so these buildings tend to be super super healthy for people who have potentially some like chemical issues for regular people who have allergies you can you can trap most of the pollutants that typically come into the house if you ventilate just through open windows and then there's of course also the the factor of resilience you want your building to be resilient if for some reason the power goes out and these buildings are resilient they can coast through power outages and stay comfortable for up to five days even if the temperature is very high in the summer where the temperature is very cold in the winter so that's a big plus right the passive house Institute US helps to transform the market that's our mission we are essentially a standard setting organization we train folks to put these principles for passive design in practice into practice over the years we were founded in 2003 initially as a nonprofit housing organization and then became a standard setting Institute and an educational Institute over the years we have trained about 2,000 professionals nationwide in using these specific standards that we have developed developed I'm sorry as well as the trained people to use these passive building principles now maybe a few words to the standard and where the standard is actually coming from so how do you know where to dial in this energy efficiency where where should we stop where where should we go to with the envelope first before we add renewables with like our goal to get to zero in the most cost-effective way the way we have determined these passive building stands and again side note real quick this is not a German concept as many folks might think the Germans in the last couple of years have popularized the system very much but really initially the term was coined here in the United States and Canada and that's really very exciting for us because there's a long tradition of high performance super insulated buildings in the country it's nothing new we don't have a technological problem problem here the technology is here the materials are here so where do where the where do these standards come from and how do we dial in this specific level of energy efficiency that we're aiming for we want to bring the building load down to a very low level as I mentioned to create a very comfortable and resilient building and we also want to allow that we can get to zero in the most cost effective way which means that where can we dial in the sweet spot between energy efficiency and where do we jump off to generate energy through renewables and this is this is a this is a very clear economic proposition if you tell folks they have to hit a certain level of efficiency and it's not cost effective nobody's going to do it so this is really critical that we have the right standards and the right methodology that guides people to this sweet spot between energy efficiency and generation to get to zero and that's exactly where our standard comes in we have certain energy targets that the designer has to meet when designing a building for heating energy to be consumed over the period of a year for cooling energy consumed over the period of one year we have targets for peak loads which essentially is kind of like a short for how big does your system get to be still all passive houses still have small backup systems for heating and cooling they're not all passive and then last but not least we also have an overall total energy limit that one has to hit because again we're aiming at this efficiency between generation and conservation and I want to hit the exact spot so you need to know what your total energy uses not just like for heating and cooling energy in the building so the designer then can use these targets and apply various strategies passive building really is comprised of five major principles first you insulate the envelope very well you don't have any thermal bridging thermal bridging meaning that there might be an a piece of material that goes through the envelope that conducts heat very well an example would be a steel beam that goes through through a facade it's very cold outside the beam would conduct the cold to the inside and if people breathe inside of the building you might have seen this and older buildings the moisture in the air could potentially condense at that spot on the inside and sometimes you in very bad cases you could even see icicles and inside of the building of ice crystals on windows so that that would be a thermal bridge so the designer would have to avoid all these thermal bridges throughout the entire envelope now the insulation level is climate specific you want to insulate the building appropriately by climate so in Texas it would not make a lot of sense to super insulate a building obviously there you want to find the right balance for insulation between heating and cooling too much insulation might increase your cooling energy second principle is designing a building very airtight because right now in our buildings we're losing a lot of energy through leaks and cracks in the building that's completely unnecessary if we seal our building up this is a very cheap way to do this actually very cost-effective then we can avoid most of the energy loss we also want energy recovery ventilators to keep most of the energy inside in of the building or we generate inside of the building to heat and cool we don't want to vent that out of the building we have then as the last principles we want to control our transparent envelope components like windows so in the colder regions he passes all again would be beneficial in the warmer regions passes all again no good right we want to employ a shading strategy so what we provide is a design guide essentially to dial in your energy efficiency as best as possible now quickly I like to end with what where the market is going right now so far we've been very successful to get a lot of designers excited to take up this design methodology and in the last five years we developed a climate-specific passive building standard together with the Department of Energy and certifications really have taken off so passports in C2JUS is also certifying buildings and initially that was happening in the single family market but now we're seeing multi-family construction to increase exponentially and even now commercial construction is coming online as well and that's very exciting for us to see because the market seems to be taking up these methodologies not entirely on its own of course and this is where you guys come in policies and developers and those who are interested in this level of efficiency durability quality help they all help make this market go and the way the market is developing right now we were very excited and hopefully we will see this development continue we are seeing an exponential uptake and by the end of 2017 we're looking at probably about five million square feet certified still small amount of square feet but the market is really picking up some steam so thank you for all your work thank you so much Katrina as you know as you heard and you've probably figured out you have to have good products in these buildings and that's part of this combination that I mentioned it's all these things coming together so I'm very happy to next introduce Kurt Reisenberg sorry who is with his executive director of the spray polyurethane foam alliance and Kurt will talk about insulation and and the roofing system contribution to energy efficiency and this is obviously a critical part of the building envelope Kurt morning everybody thought today I'd try something new usually have my notes written down on a slip of paper that I scribble down before I walk into a room like this but I'm trying it with the iPad today so you're all playing along on the new experiment with me want to thank the organizers the house and Senate renewable energy and energy efficiency caucuses of course the sustainable energy coalition and EESI for organizing this today this is a great event it's it's not often that you can get these types of interests and and and representative industries together in this type of I'll just refer to it as an intimate setting intimate here as well as in the exhibit hall but you know we come together and talk about these types of issues in our nation's capital it's a very exciting time and I just wanted to express how happy I was to be here so thank you for having us quickly on SPFA so SPFA the spray polyurethane foam alliance is a 501 C6 trade association we are membership based our members represent the value chain of the spray foam industry so from raw material manufacturing through to the systems houses the people that blend it and put all the stuff together and the special sauce through to the distributors and of course the contractors as the core of our membership by quantity and by focus of our attention the folks that install this around the United States and to some extent around the world so having that value chain under one roof does of course allow us to do some interesting things and move the industry a little bit quicker it also tends to you know but when you bring the family together push people and challenge them a little bit but overall it's a fantastic setup for us to have we focus on a lot of technical research and development activities we have a national certification program that I'll get into in just a second we have an annual convention an expo and we have a magazine quarterly magazine lots of resources on our website tech docs presentations from our past annual convention so if you're looking to learn all sorts of things about spray polyurethane foam insulation roofing our websites the place for you to go I'm not going to spend a lot of time on spray foam benefits because I think that for the most part people have become widely familiar with those unless you've been living under a rock or don't have a television or streaming it's widely used on things past show extreme home makeover property brothers Mike Holmes all these TV shows have used spray foam if anyone in the room is not familiar with it it's the stuff when they spray it into the wall looks like shaving cream expanding and coming up off the wall and then it cures and and hardens in place between the insulation their insulation applications we also handle roofing applications as an industry these are different densities and a little bit different material but it's all spray polyurethane foam it's all very durable and it all delivers the same type of energy performance if you look at and I will note that there are a couple different configurations there's open cell closed cells some tweener materials if you have questions on any of the materials themselves or the type of configurations I invite you to come by our booth and chat with me for a couple of minutes but putting all that together you know on a residential property with commercial applications as well particularly on the roofing side but putting that all together we're going after that 40% energy savings in the home that comes from increasing the our value of your insulation as well as which is particularly important the air sealing of the building you lose it an enormous amount of energy through air infiltration or exfiltration and spray foam as you can imagine when you spray it in if you've ever seen any videos it fills in all the gaps and and voids and provides very substantial energy savings along with a an our value of on the closed cell side up around a six six and a half per inch so the other benefit of spray foam is indoor air quality we've heard that mentioned a number of times here today ventilation is of course extremely important as you're building these homes and buildings tighter and tighter you know a lot of things get trapped in there that you don't realize we're in there before your pet smell your carpet furniture stuff in the attic stuff in your basement that's being if you have your HVAC system in the basement these things tend to get trapped in the house so you need good filtration and good good mechanical ventilation as you're making these homes tighter and of course we in a number of other organizations have a lot of documentation to explain how this should be done but indoor air quality is extremely important one of the spray foams benefits we had Ty Pennington speaking at our annual convention about a year or so ago and he talked about his mother who has asthma and has respiratory challenges that are triggered by allergens and pollutants and he's spray foamed his mother's house and she has been in fantastic shape ever since and that really made him a true believer spray foam allows you to seal the home keep the outside on the outside and the inside on the inside and reduce those types of triggers that are going to make life very difficult for asthmatics a couple minutes on the the PCP program that I mentioned the professional certification program for spray foam it's an ISO 17 024 accredited internationally standardized and accredited program this was developed a number of years ago we rolled it out in the middle of 2013 and this program has been growing since it focuses on insulation and roofing for the installers themselves spray foam as very much as the case for any other technology has to be properly installed to realize the performance claims that you're that you're looking for and the installation of spray foam can be a little bit technical it can be a little bit challenging so having a national certification program is sort of an easy button that's been developed and rolled out by all of the elements and and participants in the industry and the value chain along the lines of a standard is extremely important and we put this together hoping that this was going to provide as I said an easy button to commercial property owners homeowners who don't want to understand the technology want the energy saving I just want a sense that they're hiring someone in addition to the experience they have the requisite knowledge skills and abilities demonstrated by our certification program as a again as a resource to the customer so it just in the last few years we've had almost 1500 professionally fully certified professionals across 45 states we have most of the preparation but all of the testing is available online we have the participation of 35 manufacturers in this industry this is not a huge industry but that is an enormous number frankly manufacturers for an industry our size they're all participating at our 2017 annual convention we had 225 written exams and 73 field exams where they actually have to do the spraying which is more than the combined two years prior to that when we rolled the program out so that really shows a lot of growth and a lot of acceptance and participation by the industry so for again an industry our size we're very excited about that I'll take the minute or so that I have left to talk about the big picture so all the technologies and intent behind them that you see and here here today are intended to focus on using the best energy sources to make the most of that energy and use the best technologies available to make the most of that energy and to do it in a way that's sustainable and produces comfort and satisfaction for the users of the occupants so my background really quick I also spent in a past life as operations director for the distributed energy resources division of NEMA where we focused on micro turbines fuel cells PV and a whole lot of other things so my background gets to be pretty diverse and I can see where spray foam which is one of the reasons I took this job where spray foam fits as a as a big piece of that overall energy efficiency and renewable energy puzzle so looking at PV for just a second we have a new technical document which is another reason why I wanted to get up here today because it does apply to everything that we're talking about SPFA 150 photovoltaic systems and SPF roof systems this is a tech doc that was completed just in May 2017 it recognizes the self-flashing properties of spray foam on a roof again we're talking about typically PV roof applications the spray foam is self-flashing to reduce leaks water leaks and air leaks around the stanchions that are going to be holding up the the photovoltaic array this document covers an introduction of PV technology design considerations service and maintenance of the assembly warranty questions applicable codes and standards and an overview of the different mounting options because just like any other distributed resource technology you're not going to want to put it on a building that is otherwise like Swiss cheese if it leaks like a sieve that that's a widely ineffective use of the technologies that you're investing in so we hope to see spray foam more and more coupled with these types of distributed technologies gonna be able to provide on-site generation or make the most of the renewable generation so we have a lot of resources we have a presentation so we can do for you spray foam overviews because people are always looking for those we have our ISO 17 024 accredited program that we hope is a resource to you and we hope that you'll stop by our booth to talk about any of these resources and where they might fit in with type of work you're doing so thank you for your time this morning thanks so much Curt and we appreciate you returning this year and being here finally I am delighted to introduce John Rockwell you've heard a lot about the importance of ventilation energy efficiency is wonderful but if you seal up the building and you don't provide ventilation that can lead to bad things sick building syndrome so John is technical sales engineer with Zender America and we'll talk about heat recovery ventilation energy recovery ventilation a critical new product not so new product in sustainable buildings hi everybody before I start I just want to find out to know your audience before Catrine's description of the Passive House requirements who here is very familiar with Passive House levels of building performance so not a huge amount of people it's a fairly simple standard to meet and ventilation is not it's certainly a balanced ventilation is certainly a required part of Passive House ventilation but you don't need Passive House levels of energy performance to need good ventilation and the architect in me who for years and years spent endless fees on wondering about crown mold and chair rail heights and symmetry and proportion and things like that and completely overlooking indoor air quality assuming that that would just happen it's kind of a bad thing so so it's good to know who your audience is when I when I talk to people here I do want to underscore the importance of all these energy standards should have comfort as one of the primary goals all the clients that I had as an architect didn't necessarily care if it used a third of the energy of what they could already afford I mean that's important and that's critical for our natural resources but the first thing I noticed when I walk into this room is not its proportions it's just how stuffy it was when I first came in and I think that's true for almost everybody so we encounter this problem where trying to save energy the primary way to do that as Catrine already said is to make the building airtight if you stop leaks from a building that naturally occur especially when there's a difference in temperature between inside and outside and what's called the stack effect occurs you're going to encounter a lot of heat loss and so maybe some of you have master bedrooms with 10 recessed can lights that you have on a dimmer but you go up in your attic and you see that there's you can kind of see light coming through there that's a major source of leakage in your house so the most important thing to do to save energy whether you're achieving passive house levels of energy consumption or not is to make your home airtight and that flies right in the face of what so many building inspectors I've encountered say you got to let a house breathe you have to make a building breathe you don't have to make a building breathe people need to breathe pets need to breathe yes anything that has formaldehyde in it or off-gassing whatever furniture is made of in the glues that needs to be removed from a building but that can be done in a much better way than the typical bathroom fan almost all of us have switches in our bathroom that we turn on either that turn the light and the fan on or just the fan but think about it for a moment if you build an airtight home that doesn't allow air to escape very easily and you turn your bathroom fan on and 80 to 100 cfm are leaving where's that air coming from if your fan is removing air from the bathroom that means it's bringing that same amount of air into the home now what happens on a day like today in dc when warm moist air enters into a cool space the analogy would be taking a glass of iced tea outside on a day like this what instantly happens all the moisture in that air condenses because it's cooled when it gets near that cold surface and that's what can happen when you don't build buildings properly cold warm air can come in and condense somewhere in your wall cavity if you haven't taken great pains to make your building as airtight as possible that's where the resilience factor comes in that kier mentioned earlier passive house buildings and good low energy consumption buildings are more resilient they're more comfortable and that's what we all are going to immediately experience when we do proper building techniques now as far as ventilation goes the idea of building tight and ventilating right is critical and when you get low load homes with great energy efficiency exhaust only ventilation is not really going to cut it you need to have a way that is quite common in europe to do that and that is you meet the intent of the code to evacuate moisture and odors from kitchens and bathrooms with continuous ventilation out of those spaces but at the same time you bring the same amount of air through a very controlled strategy one duct in through the outside of the building it's an insulated duct and it goes to a device which you can learn more about on this brochure which i've left some at the back of the room on your way out grab one if you're so inclined there's an overview of what a heat recovery ventilation system does i'm at my booth in the gold room i don't know what room that is the gold room booth 39 and come see how that works but basically you're exhausting from bathrooms and kitchens same amount of air same volume of air is coming in in a very controlled way now you might say why don't i just use my windows for ventilation well on a day like today you would be increasing your air conditioning costs right you don't want to leave your window open on the day where it's 90 and very humid or even if you live in san diego where the temperature is quite nice outside if you live in a downtown urban environment you can't really leave your windows open if you live in brooklyn you're not necessarily going to leave your windows open the street sweepers might go by and cause all sorts of contaminants to be able to come into your building so an airtight building does not mean that it's stuffy it means that with proper ventilation you can have superior indoor air quality compared to the outside and if you go to the lengths of making a building really airtight for perhaps by using spray polyurethane foam and having very very rigid airtight or very low air air changes per hour you're going to need balanced ventilation so provide air tightness bring fresh air in filter it as any good hrv or erv system does and you will provide superior indoor air quality now who's heard of an hrv prior to today hrv is just a smattering of people heat recovery ventilation is a means by which when you bring that fresh air in and are exhausting stale air the two meet in a contraption called an hrv or an erv hrv is simply transferred temperature so if it's 70 degrees inside and in wintertime it's 10 degrees outside during the polar vortex here you have a temperature difference of 60 degrees you don't want to use your window for fresh air ventilation it might feel good at first but your thermostat is going to recognize that you're going to use more energy even though you've taken great pains to make your building low energy in a heat recovery ventilation device you can capture about 90 to 95 percent of that temperature difference simply by the air streams passing one another through airtight an airtight heat exchanger and as much as 95 percent of that temperature difference is recovered so your zero degree air as it comes in is warmed up to about 60 to 65 degrees and then is supplied to spaces keeping co2 levels down enhancing sleep keeping cognitive function and going it's quite an amazing system now in a climate that has severe moisture conditions like we have outside today an hrv is not going to cut it you need something called an erv that's nothing more than an energy recovery ventilator that has a membrane in it that also allows heat transfer from one air stream to another but also transfers up to about two-thirds of the moisture difference in the air so if you're bringing in washington dc air on a day like today and you have a home that's well insulated and doesn't require a lot of cooling you may have met your cooling loads by air conditioning but you haven't met the dehumidification requirements which is really where a lot of the discomfort comes from you can dump a lot of that moisture that would otherwise be brought into the house of the hrv but divert it to the outgoing airstream with an erv you're lowering your cooling loads as well and that's how a well-designed balanced ventilation system can work in harmony with the other aspects of low thermal bridging good windows good air tightness and low energy consumption a low energy budget to make a home work really really well or any kind of building really whether it's commercial or individual single family homes multifamily housing schools yoga studios that all benefit from balanced ventilation any questions good thank you take a brochure amen to that building as a system and by the way um i will mention a resource that i think is is very very useful um called the whole building design guide it's managed by the national institute of building sciences which by the way is uh has a congressional charter to advise congress on um building related issues but the whole building design guide wbdg.org talks a lot about how all these systems interact we have a couple minutes for we have a couple minutes until we have to end this panel so i'll leave it to everyone whether or not um we want to do some q and a or you want to take a little have a little break there's a question did everybody hear the good question difference between all the different building standards there are codes and standards there are building rating systems there it's apples and oranges there's a it can be very confusing would anybody like to catrin ah excellent technology um so uh it's uh our trainers um generally like to say building codes are kind of like the worst building that you're allowed to build by code like um so that's the kind of like the bottom line really and then everything beyond that um is a step up there are some standards that that ratchet up the green building aspects but not so much necessarily the energy efficiency so you want to be looking at which additional standards or rating systems are looking at a holistic green rating program and and how are they looking at energy um and um so most of those programs will combine those two things green building aspects as well as energy and and uh it's up to the consumer then to decide which level you want to attain um so yeah no they don't uh code you have to meet code but and and that right yeah but and then after after that you you pick what your client would like to go to yeah sure okay so a house that has maybe built in 1800 and is extremely drafty and has never had any insulation put in it or any air sealing may not experience the regular benefits of balanced ventilation but almost any home that is built today that has to meet the a lot of energy requirements generally around three air changes per hour even a house around five air changes per hour is done with a blower door test i'm sorry if that means nothing to you but it's a way of testing relative leakiness from one building to another even as i want to say as high as five air changes per hour our culture's gotten to the point where builders can build in a way where you can get very very good air tightness and if you only use exhaust only strategies you're not you're not getting full effectiveness out of that exhaust only fan yes it may be working yes it may remove odors immediately but it may be struggling the fan may be struggling because you build the house so airtight or you'll have to open a window so below about five air changes per hour is done by a blower door test at 50 Pascal's pressure difference you will benefit greatly from heat recovery ventilation that doesn't mean that the roi is next year because the cost of installing a cheap bath fan is very low but it isn't just about electric consumption it's about comfort in an hrv system you are intentionally providing fresh filtered air to sleeping areas that air in the daytime when there's nobody sleeping generating co2 that air cascades out of those bedrooms ventilates the rooms that are not bedrooms and then makes its way to the exhaust locations creating an entire scheme of continuous ventilation for the whole house and you intentionally want to ventilate a house about 0.3 air changes per hour so every three hours all the air has been replaced with fresh filtered air not by opening a window but by high heat recovery your second part of the question is it's a little harder to do in retrofits because you have to open walls and put some duct work here and there but if you see i don't want to get into any proprietary information but we have a unique duct system that does fit into two by four stud walls you can come see me at the booth in the goal in the gold room about that so thanks oh good wouldn't everyone love to walk out with exactly that number to say yes or no yep no i'm gonna what i'll say is that if you can make your building airtight and properly insulated for your climate zone you will reduce the size of your heating and cooling system so substantially compared to the way they're typically designed that there's room left over for a ventilation system okay so i'm not going to give you a percentage you can calculate the amount of energy recovered by a heat recovery ventilation system and calculate the storage capacity of a cubic foot of air and calculate btu's and apply a cost to that i can't do that on the fly right at this moment but let's put it this way anyone who's sort of mini splits and knows that for one unit of energy applied to a air-to-air heat exchanger mini split you get four to five units of energy out of that with a ventilation system for every unit of energy you put in you get about 20 to 30 units of energy saved so the coefficient of productivity is gigantic with the heat recovery ventilation system so the higher efficiency it is the better it is and that's critical so thank you i think we're going to have to end on that note uh and make room for our next panel thank you all so much for coming thank you to our panel really really appreciate all of you being here