FLASHBACK FRIDAY – Paul Francisco – University of Illinois at Urbana-Champaign – Ventilation and IAQ – EPISODE 448 (Air Date: 2-17-2017)

Air Date: 8-3-2018|Episode 512



00:00 Joe: Paul Francisco runs The Indoor Climate Research and Training Group at The Applied Research Institute of the University of Illinois, Urbana-Champaign. He does both research and training on issues related to home performance, and his research focuses on indoor air quality, energy efficiency and emphasizing field measurements. His training focuses on teaching practitioners building diagnostics and Health and Safety. He’s also been a trainer in that area in the home weatherization assistance program. He’s done extensive work on curriculum development for weatherization workers and also research on energy efficiency and indoor air quality in existing homes. He is also the current Chair of the ASHRAE 62.2 Ventilation and Acceptable Indoor Quality in Residential Buildings. He’s got his Bachelors degree from University of Delaware and a Masters in Mechanical Engineering from the University of Washington. Hello Paul, do we have you on the line?

00:56 Paul: I’m here, thanks for having me on, Joe.

01:00 Joe: Great to have you and been trying to get together with you for a while now and I’m glad we were able to pull this together. First, yeah, let’s talk a little bit about what you do at the university. Tell us a little bit about your position at The Indoor Climate Research and Training Group.

01:17 Paul: So our group, I run the ICRT group, as we call it. Indoor Climate Research and Training, ICRT, and we’ve been, for about 10 years now, we have been the group that has run the training program for the Illinois Home Weatherization Assistance Program. We have, it’s now grown to a 10-week training. And so we administer that as well as some additional classes on air sealing and furnaces and we’ve been running a lot of QCI and energy auditor classes, to get people certified. Then on the research side, we’ve got a number of folks involved with several research projects that primarily are focused on practical issues in the field, that people doing retrofits face, that usually specially related to indoor air quality, and trying to figure out how to provide good indoor air quality and good energy efficiency, at the same time. How we can get both of them instead of sacrificing one for the other.

02:23 Joe: Tell us a little bit about some of the current research and why it came about. You mentioned the practitioners in the field, they come across issues when they’re dealing with energy efficiency. Give us an example of that and the type of research you’re going to help them out.

02:39 Paul: Sure, so we’ve been doing a lot of work in the last seven years or so, on radon. And the concern there is that people have been really worried that as we’re air sealing homes that there may be some increase in radon. And a lot of our work has been in the area… In radon, a lot of our work has been in the area of evaluating different measures that can be done within the context of weatherization, to try to keep radon on levels from going up. So, preserve the “do no harm” principle. So does the current ventilation requirement for weatherization help to keep radon levels from going up?

03:27 Paul: Are there other measures that we can be doing that can keep levels from going up? And that was an issue because there was a real concern back when the National Weatherization Evaluation was done in about 2010, during the time about radon. And so, that was an issue that was brought to us and we took on that topic, and we’ve been doing, like I say, a lot of work in that. And another thing we did was a project where we evaluated the impact on contaminant levels, with and without using the 62.2 standard, as it was in 2010 for ventilation and weatherization homes. We did homes that used the 62.2 ventilation standard versus homes that did not use that standard and what were the impacts on indoor air quality. And that was because a lot of people were asking questions like, “We’ve gotta put these fans in. Is it doing any good or is it just wasting money?”

04:18 Joe: And what I’ll do, I’d like to come back to that second one. Let’s go, go back to the first one. When you were talking about the research on radon and weatherization. You mentioned a ventilation requirement for weatherization and I’m not sure listeners, and even I’m not familiar with what that requirement is. Is that an Illinois requirement? Is it a program requirement? Is it something from the DOE? Can you expand on that for us a little bit?

04:45 Paul: Sure. Back in 2011, DOE came out with Health and Safety Guidance at which point they required that all homes that are getting weatherized, using DOE funds, must comply with the ASHRAE 62.2 ventilation standard. So it is a national requirement from DOE for the weatherization program.

05:06 Joe: Oh, okay, and that’s 62.2 and that would be version, which version?

05:12 Paul: Well, right now, people are largely using the 2013 version, although we expect the 2016 is going to be coming online. Basically DOE says we should be using the most recent edition and recognizes that you can’t start using the new edition the very first day it’s available. So there’s gotta be some opportunity for people to learn what’s in it and train. So it’s typically the beginning of the next program year after the new version comes out, is when you’re expected to start using it.

05:42 Joe: I see. So it started with the 2010 version. Most would currently be doing 2013, and within, let’s say, another year or so, they would be expected to move to 2016?

05:56 Paul: Correct.

05:57 Joe: Okay, okay and then a little later in the interview I’d like to get into a little about the difference between how things have changed during those years. But before we do, I wanna talk a little more about this radon issue because it’s something I don’t think we focus enough on here at IAQ Radio and also in the indoor air quality world in general. So how does… Tell us a little more about how what your research tells us with respect to how weatherization affects radon levels in homes.

06:31 Paul: Sure. So there was a big national evaluation study done back around 2010, and about 500 homes were measured. And in that study, the determination was that based on weatherization practices at that time, weatherization health and safety practices have changed since then but at that time, there was an increase of about 0.4 picocuries per liter which is the EPA guideline for where you should consider remediating your home, is 4 picocuries per liter. There’s a lot of people who say, “Hey, you should just… There’s not really a safe level so, you should mitigate at any level, but the EPA guideline is 4.” So we were seeing an increase of about 0.4 picocuries per liter from that. And so from that there was then a little study on 18 homes that said, “Well, if you put in the ASHRAE 62.2 ventilation, what does that do?”

07:35 Paul: And the answer was generally levels were reduced. So now the question is, if there was back in 2010, a little bit of an increase, but then there’s evidence that some of the practices we’re doing now like the ventilation may be improving it, then what are practices now like? So we don’t know right now what current practices are doing with regard to radon and so that’s one of the big research projects we’ve got going on right now.

08:06 Joe: When you say current practices that would be again doing weatherization, but bringing the home as you do at up to ASHRAE 62.2 2013?

08:19 Paul: That’s currently, yes. That’s currently what we’re doing. We’re also looking at making sure the ground covers are done very well because the source of radon is the ground. So if we can make sure that the ground covers are being done very well then that could have some potential impact. And then we’re also… Another thing that we’re focusing on is sealing sump pumps, making sure that they’ve got sealed sump pump covers on them. And obviously not all homes have those, but where they do, doing that measure as well. And really the big focus is we’re air sealing the home. That changes the overall air flow dynamics. So do these other things. Keep, in terms of the sump pump covers and the ground covers, does that help keep radon from coming in in the first place, and then the ventilation, does that help remove whatever does come in.

09:09 Joe: And where are the measurements typically taking in these research studies? You take them in the lowest level of the home or in multiple levels, or how do you do that?

09:19 Paul: For radon studies, we will measure on the first floor and in the basement of every home. So if it’s a crawl space home, it’s only on the first floor and if it’s a home with a basement we’ll do it in the crawl space and the basement. And in the studies we’ve done, we’ll do it in the basement whether or not the basement is occupied, but we record that information because the EPA guideline is based on the lowest living level. Sometimes that’s the basement. Sometimes it’s not. So when we report out, we’ll use the lowest living level, but we do like to know what’s going on in that basement space if there is a basement.

09:53 Joe: I think most people when they think of radon, they think of radon mitigation systems, both passive and active types. And I’m assuming from this conversation, I wanna make sure I’m accurate on this, Paul, that those are not being added to these homes. You’re just looking at the effect of weatherization that brings it up to the ASHRAE 62.2 standard ventilation-wise. They’re not also adding some kind of sub-slab depressurization or something like that. Is that accurate to say?

10:28 Paul: That’s correct. It is not about radon mitigation. It’s about doing no harm. So if the level is high before we get there, we’re just trying to make sure it doesn’t go higher.

10:40 Joe: I see.

10:41 Paul: Basically, just because we showed up doesn’t mean we bought the problem in weatherization, but we do wanna make sure that if there is an issue, we don’t make it any worse.

10:51 Joe: And while we’re on this topic, I know we were headed down a little different path than we maybe expected, but this is very fascinating to me and I think to a lot of our listeners, as far as… Have you done much work on sub-slab depressurization and then looked at the possible or are you aware of the research on the possible effects that may also have on moisture in residential properties?

11:18 Paul: I have not done any work myself on that, although one of the studies we’re currently doing is going to be getting some data on that. We just have not completed that study to do the analysis. I have seen some studies that have indicated that you do also get some drying of basements when you have the sub-slab depressurization. Partly it’s also extracting moisture from the soil, and partly, there may be small leaks in piping and because it’s de-pressurizing, it’ll potentially remove some basement air that has moisture in it as well.

11:55 Joe: Okay, and that’s something that you’ll be clarifying a little better once you do your research, is that accurate to say?

12:02 Paul: We’re hoping to. We are collecting moisture measurements in one of the studies we’re doing. We’re collecting radon and moisture measurements in every home in both basements and first floors, and we’ll see what it says. I’d like to think we’ll be clarifying, but we’ll have to look at the data.

12:21 Joe: Interesting. Alright, I’m gonna jump ahead a little bit. Cliff, anything you wanted to… Did you wanna jump in here at all?

12:29 Cliff: No, I’m good Joe.

12:31 Joe: Okay, let’s talk a little bit about something I’ve noticed Paul, and I don’t know if you’re seeing this as well. I’m sure you are. You deal a lot with weatherization people and I’ve seen a push recently for energy raters and weatherization people to add indoor air quality, or what some people refer to as healthy homes and healthy homes consulting to their services. I’m wondering if you’re seeing the same thing, and what your thoughts are on that as an additional service line, I guess. They’re dealing with indoor air quality whether they in the past recognized that and or focused on that whatsoever is I guess a question and then I’m wondering if you’re seeing the same thing?

13:15 Paul: Absolutely, and I think this is a really great trend that we’re seeing, because we know that indoor air quality can have an impact on people’s health. We know that there are a lot of people who have various ailments such as asthma, the respiratory issues, etcetera, as well as concerns for say the elderly with slips, trips and falls, where perhaps there are things that could be going on in a home that are not easily found by a visual inspection. For example, bird’s nests in the attic or something like that, where a normal just visual inspection of the home might not notice it. And so this is an opportunity to bring building science and healthy homes principles together.

14:00 Paul: And so I think while that might not be focused on the energy side so much, that bringing building science and healthy homes principles together will provide us the opportunity to do much more comprehensive evaluations of homes where there are people who have chronic ailments, and potentially find some solutions that were not there previously to help people live better lives. And so I see this as something where if we are able to really get it right and get it going, you can see a lot of health programs, hospitals, other organizations, community health programs, things like that, that could really look to these home energy raters, energy auditors for additional knowledge to find problems that are not otherwise being located.

14:52 Joe: And I guess you mentioned the bird nest thing for a reason. Those guys are often times up in attics doing air sealing, looking in areas where you said a typical home inspector or maybe even someone doing an indoor air quality inspection wouldn’t necessarily look that closely. Is that accurate to say?

15:14 Paul: Absolutely, and I got interested in indoor air quality because of that. You’re right, it was not just something off the cuff. I was doing a project on duct leakage, and we were focused on supply leaks, and there was a home where there were two children with very severe asthma, and they had burned out two furnace fan motors by putting in better and better filtration trying to clean the air to help their kids’ health, and this was a horizontally mounted furnace in a crawl space, and they had us out there to do duct sealing, not because they were worried about energy, but because they were trying to help their kids’ health. And one of the guys on the job took… The return was on an interior wall cavity. Everybody figured it was just interior wall, it doesn’t matter. One of the guys on the job took the grill off that was low on the wall, looked up and saw the rafters. They hadn’t put a cap on the top of the wall cavity and there was a bird’s nest sitting there. So there was a bird’s nest in the return. And we looked at that and said, “We can’t leave it like that.” 15 minutes later it was sealed, and the mother thought we were the best people that had ever shown up at her house I think, except her family. So I recognized then that there are all these things about indoor air quality and health, that people who can understand buildings and look behind the walls, look above the ceilings, look below the floors can find that most people won’t.

16:41 Joe: Interesting. Let me get one more question then we’ve gotta take a quick pause to thank one of our sponsors, but I think this is a fairly quick one. Is the program that you’re in with the University of Illinois Urbana-Champaign, is that common nation-wide where you have these university and state weatherization programs working together?

17:06 Paul: It’s extremely rare. There are a number of accredited training centers. Our training center is2 IREC accredited and there are a number of IREC accredited weatherization training centers, but there’s not more than two or three that are associated with universities.

17:22 Joe: And what’s IREC accredited? What’s that?

17:24 Paul: IREC is the Interstate Renewable Energy Council, and they are an accrediting body and DOE when they were wanting to get their training centers accredited to really demonstrate that they were meeting the curriculum requirements, and the business requirements. IREC as an accrediting body was tapped to be the accrediting body of training centers. And there’s… I’m not sure how many weatherization training centers are accredited by IREC right now. It’s somewhere around probably 18 to 20.

17:56 Joe: And then you’ve got other programs out there, like the BPI program and others, do they work together at all with IREC or is that just a separate thing?

18:10 Paul: Oh they work together with IREC. IREC is accrediting curricula and job task analysis and then what BPI is doing, is setting standards and doing the exams. So when we do the training for people using our IREC-accredited curriculum, that is intended to then prepare people to be able to take and hopefully pass the exams that BPI administers.

18:39 Joe: Okay, okay. That helps me. This has been fascinating, Paul. I appreciate you joining us. We’re gonna stop for just a moment. We gotta thank one of our sponsors, and we’ve got an event coming up next week we wanna let people know about, and then we’ll be back. We’re gonna do another 10 minutes with Paul Francisco, then of course we’ll go to half-time. John.

18:57 Joe: It’s the second annual Indoor Environmental Science Forum coming to the DoubleTree Hotel, Tampa Airport in sunny Tampa, Florida, February 21st through the 24th. Join industry leaders and educators as they share their knowledge and supporting science with you. See the latest equipment and solutions from exhibitors. Network with sponsors and industry insiders. It’s two full days of in-depth coverage of water damage, assessment, protocols, mold remediation, solutions, and legal issues. Don’t miss this important two-day industry forum beginning this February 21st with a welcome reception, and wrapping up with a live IAQ radio broadcast Friday the 24th, featuring Radio Joe and the Z-Man and their guest John Lapotaire, Richard Alexis, and industry watchdog Pete Consigli. Register now at indoorenvironmentalscienceforum.com or call 954-562-6093 for more information.

20:00 Joe: Alright, time’s running out. So get those registrations in for next week’s event. Let’s continue the discussion here with Paul Francisco, University of Illinois at Urbana-Champaign. Paul, you’ve done a lot of interesting… This is very interesting. I always love these interviews when I find out people are doing things that really, I’m very interested in and match kind of my passion, which is research to practice. We do a little event every year called the Healthy Building Summit where we try and bring people together that are both in the research world and the practitioner world, and get them looking at each other and trying to make sure that the researchers are doing things that are of use to the practitioners in the field. And you’ve done a lot of that kind of thing, and I’m wondering if you could maybe tell listeners a little bit about some of your key research findings or others that you’re aware of that you would like to see more indoor environmental quality consultants and remediation professionals become more aware of.

21:04 Paul: Sure. So I mentioned a little bit ago earlier in the show that we did a study that compared the impact of the 62.2 as of 2010 ventilation standard versus not using that. And we saw in that… In that study, we measured formaldehyde and total VOCs, volatile organic compounds. We measured humidity. We measured radon. We measured carbon monoxide and carbon dioxide. And what we saw was that for most of those contaminants, we saw some pretty statistically significant reductions in those contaminants when the 62.2 ventilation was used, and except for formaldehyde, we did not see statistically significant reductions in contaminants when the ventilation was not used. So that indicates that yeah, the ventilation is actually doing what it’s supposed to do. It is reducing contaminants. It is… Therefore should be improving that component of people’s health. We also did health surveys in that, and there were a few items such as headaches that seemed to be lessened when the ventilation standard was used. So that was one study that, yeah, the ventilation actually does seem to work.

22:25 Paul: Another thing that I thought I would throw out there is that two of the contaminants that seem to be of most interest right now in the context of health are particulate matter, PM 2.5, so really small particles, and formaldehyde. There was a study a few years ago done out of Lawrence-Berkeley National Laboratory that identified those as two of the more important contaminants. And cooking is one of the major sources of PM 2.5. I think it’s good for people to recognize that particles can be extremely important and getting rid of them from the home when you’re doing activities that produce them can be really important. So it’s good to have vented range hoods and then actually have them be used. So that’s another one I thought I would mention. And something else that I think is interesting was a little bit of a surprise to me when I first learned it. It was a number of years ago that I learned it, but the science is getting stronger to support this, that there’s actually more association between dampness and health than between actual mold and health. It doesn’t mean there’s not an association between mold and health outcomes, but the association is actually stronger between dampness, damp homes and health, than whether or not there’s actually evidence of mold within the home.

23:48 Joe: Interesting. Now the first one was particularly… Caught my attention because… And maybe the first and the second. I’m not sure if I got this right, but in the first one you mentioned doing some testing. First of all, where was that done? Is that all up in the cold climate, like up in the Chicago area, or was that done in other parts of the country? And how many homes were you looking at?

24:11 Paul: So we did about 80 homes and about two-thirds of them were in the Chicago area, and the other third were scattered around Indiana next door to us.

24:23 Joe: Okay, and did you notice any regional differences at all?

24:28 Paul: Well, there’s not a huge regional difference between the two. The one thing we did notice really was that the radon levels in Indiana were a good bit higher than in Chicago. Chicago is not in a really high radon area. So we started with less radon there, whereas in Indiana there was definitely a good bit more radon to start, and part of that is the lake effect. Typically, if you look at the radon map, you’ll see that where there are large bodies of water, radon tends to be a little less. And so, with Lake Michigan right by Chicago, it tends to have lower levels than some other places in the Midwest.

25:10 Joe: And I noticed that you said that, and correct me if I’m wrong, that the ventilations of the 62.2 standard reduced quite a few of the contaminants that you mentioned, but it didn’t seem to reduce the formaldehyde. That, if I’m not mistaken, sort of matches other data that people have gotten in the past that maybe ventilation isn’t as good with formaldehyde as it is with other types of contaminants. Is that… Did I get that right?

25:45 Paul: Sort of. That we actually saw significant reductions in formaldehyde both with and without using the ventilation, but they’re really pretty much identical. So we can’t really attribute it to the ventilation as much as just the overall weatherization effort to reduce formaldehyde. Now, there are some… One thing to keep in mind is the study really used exhaust-only ventilation. And there are some studies that have suggested that exhaust-only ventilation does not really seem to have any impact on formaldehyde, in part because some of the formaldehyde is in the building envelope materials, whereas we do see some statistically significant impacts on formaldehyde; there are some other studies, not one that we’ve done at this point, that have shown impacts on formaldehyde, beneficial impacts on formaldehyde using supply ventilation, where you’re pushing things out. And so, since the formaldehyde is partly in the building envelope materials, if you’re pushing out then you send it outside. If you’re doing exhaust, then you’re pulling it in.

26:46 Joe: And Cliff, you have a follow-up on that?

26:50 Cliff: I do. Paul, in terms of the formaldehyde studies that you did, did you try any absorption, trying to remove the formaldehyde by scrubbing the air with carbon or potassium permanganate coated medium?

27:06 Paul: No, we did not.

27:08 Cliff: Okay, thanks.

27:08 Joe: Paul, before we go into a little more on ASHRAE 62.2, this whole weatherization and IAQ thing just fascinates me. I tend to agree with you, I think it’s great that the weatherization guys are getting more involved with indoor environmental quality, but I wanna go back a little to weatherization with respect to people doing blower door testing. I took a HERS Rating course, a RESNET I guess it was, oh, it’s four, five, six years ago now, and they were doing blower door testing, and I asked, “Do you have people leave the house when you do the blower door testing?” and the instructor told me, “No, that’s not necessary, unless there’s mold.” And I just found that… Actually I found that alarming, I guess you would say, because while we were doing that testing, I have a touch of asthma, and the thing that really aggravates the heck out of my asthma is actually drywall dust, and after going around and blower door testing homes for a day or so there, I could feel it kicking up. And I just thought to myself, if I was in home with a kid with asthma, I would be scared to death to do a blower door test and leave those kids in there. What do you guys teach about that?

28:29 Paul: Well, honestly, we don’t really teach a whole lot about it, but what I would recommend in general is that it isn’t just mold. As you identified, there are a lot of triggers of health impacts that are not just mold. So what I would say is if there is somebody who is sensitive, it would be a good idea for them to step outside while you’re doing the blower door test. I wouldn’t say that it’s necessary for everybody to leave, but I think it would be good practice to have people who do have these chronic issues like asthma step outside when you’re doing the test. ‘Cause there are a number of things you could be stirring up, many of which are just… They’re being emitted in the home all the time, but if you can have them step outside while you do it, that’s just one less thing to worry about.

29:22 Joe: Let’s talk a little too about duct sealing. You did mention duct sealing earlier, and I got the impression the duct sealing you were talking about at that point was when you had some ducts going to an attic, which would generally be an unconditioned area of the home. I wonder if you could tell listeners a little bit about your thoughts on duct sealing, how important it is when it comes to energy efficiency, and then also any thoughts on how duct sealing might affect indoor air quality as well? I don’t know if there’s any research on that, but I’d be interested in learning.

29:57 Paul: So duct sealing can be extremely important in energy efficiency. If you have ducts running outside of the conditioned space, so in attics or vented crawl spaces typically, if you have a leak of a noticeable size, and there’s a lot of homes with that, it can be a huge penalty, especially on the supply side. In heating climates, supply leaks are extremely important and return leaks don’t matter very much from an energy perspective. In cooling-dominated climates, it’s a little more balanced. But if you’re in a heating-dominated climate, you’ve got a gas furnace running, you’ve got a 10% supply leak, you could be throwing about 20% of your energy away. So 20% of your heating energy, that’s a pretty significant amount for just one particular measure. So when there are significant duct leaks, it has potential to be the single biggest energy improvement you could do in your home.

30:57 Paul: On the cooling side, like I said, the return gets to be more important. Oftentimes in cooling climates, you’re in really hot attics, and it’s a little bit harder to cool your home if you’ve got leaks that are pulling 140 degree air in before going across the coil. You can have some really significant impacts there as well. But yeah, if you have leaks, it can be huge. If all the leaks are to inside, you’re not gonna get much in any energy benefit. It’s really only if the ducts are outside.

31:29 Paul: As far as duct leakage in IAQ, there’s pretty limited actual data on that. But anecdotally, there’s I think pretty broad acceptance within the industry that duct leaks or duct imbalances are probably the single biggest cause of backdrafting of water heaters and natural draft furnaces. So there’s some combustion safety concerns there. Also, if you have pressure imbalances, it can certainly be drawing other contaminants in. If you have… If because of duct leakage you end up de-pressurizing the home, you could be bringing in additional radon or other soil contaminants. You could be bringing in whatever’s outside. So it essentially… A supply leak acts like an exhaust fan. If an exhaust fan in your area could be a problem, or in your home could be a problem, a supply leak will be a problem as well. And return leaks, they end up pressurizing the home, but they are also going to be drawing whatever it is that’s in the air where the leak is located, whether it’s in a crawl space, or an attic, or a garage.

32:46 Joe: So they’d be both a pathway and a pressure… We always teach the four Ps, people, pollutant, pathway, pressure. Those would be both. I’ve got a question on ducts. I see this more in the north in the cold climates, but I’m wondering if you have any thoughts on panned return duct work. It’s just so much easier to do, and contractors do it all the time. Is there any good research that indicates that they’re a problem, either energy-wise or IAQ-wise?

33:22 Paul: In my mind, the panned joist returns should get a product recall. I really can’t stand seeing panned joist returns. It’s possible to make them be not a major problem, but I’ve measured duct leakage in homes with panned joist returns, and they’re almost always extremely leaky. I’ve had homes where 50% of the air is coming from a damp crawl space because they have panned joist returns. And it’s easy, very easy to have 20% to 30% leakage any time you have a panned joist return. You can try to seal it and that can certainly have some impacts, but you’re still having… There’s parts of the ducts you can’t get to, essentially, because you’re talking about the subfloor. So yeah, I really do not like them. I would like to see them not allowed…

34:24 Joe: Interesting. And how would you…

34:24 Paul: And removed and replaced any time you can.

34:26 Joe: If you’ve got one and you want to improve it, at least air leakage-wise, is there a method you recommend for sealing it up a little bit better? Would you put some tape on the edges? You’d want to caulk it, obviously, before you even put it in there, but after the fact, that can be tough.

34:44 Paul: Well, if you have a panned joist return and you do wanna seal it, there’s multiple parts. One is where you’ve got the ends, and there’s oftentimes some pretty large gaps at the ends where they’ve folded the metal up to the subfloor. Getting those sealed with, often mastic, is a good thing. And then… Mastic is really the material that I prefer to use whenever possible. You can run it along the entire length of the panned joist return if that’s possible. Now, sometimes the gaps can be quite large, and now you’ve got to do something else, like use mesh tape so that you’re essentially breaking a large hole into a lot of smaller holes, and then the mastic can do it. That’s generally gonna be my preferred method. Duct tape, certainly not. Really high quality metal tape can work if what you’re taping it to is relatively clean and smooth, but often it’s not. So the mastic would again be my preferred method.

35:52 Joe: Okay, I appreciate that. Let’s move on a little bit to ASHRAE 62.2. Before we leave the energy efficiency, I’ve seen some recent reports that maybe we’re not getting as much bang for the buck on energy efficiency programs as we thought. I wanted to give you a chance to comment on that.

36:16 Paul: Well, yeah, I think it’s true. We don’t always get what we thought and there’s a lot of potential reasons for that. And I think there have been a number of evaluations over the years within weatherization programs that have said that typically around 70% of projected savings is what you actually end up realizing on average. So it’s not a real surprise. Doesn’t mean they’re not cost-effective, we just might not be getting everything we thought. I think the exact mechanisms we’re not sure about exactly. I think a lot of it is likely going to be some of the modeling inputs. If you have an un-insulated wall or an un-insulated attic, there’s a huge difference in energy loss between having R1 and R2. So when you have no insulation, just a very small error in what you put in in terms of your R-value, you can have a pretty significant difference. So I think that’s one of the sources. There may be some workmanship issues as well. A lot of people say it’s take-back, that now the people are not using their… Now that they are using less energy, they might turn up the thermostat or do some other things. There’s really very limited evidence of that, so that does not seem to be the big factor.

37:37 Joe: Okay, very interesting. Let’s jump over to 62.2 a little more detail. We’ve mentioned it quite a few times here already and you’re still the current chairman of that committee. That committees has had its share of people poking at it, and I’m sure you’ve grown thick skin over the years in dealing with that [chuckle], but I’m wondering if first you could maybe give people a little run down on some of the changes I guess. We mentioned 2010 and then there was 2013, 2016. Can you kinda give us a general description of how things have changed over the last, what, six years, I guess?

38:16 Paul: Sure, I’ll try to remember some of the most significant changes here. One of the really big changes was, through the 2010 version, there was a default infiltration. If you didn’t do any measurement like with a blower door, you’d got to assume you got a certain amount, and then if you did a blower door test, you could get credit for more infiltration than that, and that was put in back when homes were not being built as tight as they are now. And so, in the 2013 edition the default was removed, and so it didn’t increase the target rate. It just removed the part that we assumed that you got. And so now, if you want to get any credit for infiltration, it actually has to be measured or estimated using a blower door test. So that was one of the really big changes.

39:06 Paul: Another thing that’s happened, this happened between the 2013 and 2016 versions, was in multi-family buildings, once you had four storeys or up, everything had been in standard 62.1, which was for non-residential and residential four storeys and up, where a 62.2 is only three storeys and lower. In the 2016 edition, we now have it done differently. All of the common spaces belong to 62.1 still, but the dwelling units, the apartments in multi-family buildings, those are done by 62.2 regardless of the number of storeys in the building. And that was done in part because it didn’t really make sense that the units on the second floor apartment would have different requirements depending on whether there were one or two storeys above them. So we did that change.

40:01 Paul: We’ve also done a fair bit in controls and one of the biggest changes there is it’s always been this requirement for readily accessible override that a lot of people interpret it as you have to have an on-off switch. So yeah, you put in this continuous running fan and then you put on an on-off switch, and a lot of people shut it off, and that was not what we had really intended. And so there was a change that’s in the 2016 addition now, which clarifies a little bit more of what the intent is there, and it allows things, like a circuit breaker, to be… A labeled circuit breaker to be the readily accessible override. Basically, the idea is that we want people to be able to turn the fans off for maintenance, that’s the single biggest reason. So you’ve gotta have some way to turn it off so you can clean it or other maintenance but it shouldn’t be something that just makes it easy to shut it off permanently.

41:00 Paul: So that was a big change. I’m trying to remember when carbon monoxide alarms came in to the standard. I think that was first into the 2010 edition, so that wouldn’t be a change since then. We’ve increased the amount of flow required for kitchens. If you don’t use a range hood in new construction. In existing homes, the levels are still the same for kitchen ventilation. Recognizing that there’s some limitations in what you can do when the house is already built. But for new home kitchens if you don’t use a range hood you’ve got to use much more flow. So that was, I think, a significant change. Trying to think of what else has been real big. Those, I’d say, are probably some of the biggest changes that we’ve had in the last six years and a lot of it’s really been trying to make it work better for existing buildings with the idea that, in new construction it’s much easier to just do whatever it is that’s required but in existing homes it can be a challenge. So, how can we get to the same end point in ways that account for the fact that you can’t do it right the first time?

42:23 Joe: And where are we with respect to these things being required by code?

42:29 Paul: Well, you can find certainly some codes that have some of the types of text and language that 62.2 has, but you don’t really have codes at this point, just saying do 62.2. You have programs that will say, do 62.2 and you’ll have those for both new and existing construction. But just in terms of the fundamental code, we don’t really have that and honestly, I don’t know when we might see that happen. I hope that it happens at some point. I think one of the things we’re gonna need to do is… 62.2’s under continuous maintenance, and one of the things that happens is you change one thing here and you change one thing there. At some point, we need to spend a little time not changing the requirements, but making it just easier to follow. I think that it would be a lot easier to get it into codes, if we just made it simpler to follow and had the requirements much more clear.

43:32 Joe: I think that’s a really valid point there. I do indoor air quality but I also have a small construction company and I can’t… My son runs that and I think he would have a little trouble following it as it is right now, if he had to put it into some… Even in new construction, it can be a little tough. The language is a little rough I think but, I think you bring up a really good point there. So what about the… Let’s talk a little bit more about 62.2 and regions of the country. I hear people banter about the hot, humid climates and bringing in the amount of outdoor air and hot, humid climates that’s required and 62.2 is gonna cause them problems or at least make them dehumidifier. I wonder if you wanted to comment on that a little bit.

44:24 Paul: Sure. It’s a really hot topic. And we have a lot of debates about that obviously, and there are certainly situations where it could potentially lead to issues and there are a number of factors that go into that. One is what type of ventilation are you using? Another is what’s going on in the home? For example, there’s some pretty good anecdotal evidence that if you have vinyl wallpaper in a hot, humid climate, then exhaust-only ventilation is just probably not a good idea. Doesn’t mean you can’t ventilate, you just probably don’t wanna use exhaust-only ventilation. But one of the things that I think is really important to understand is that the ventilation rates are not just about moisture. We can’t ignore moisture but it’s not just about moisture. It’s about particles. It’s about formaldehyde. It’s about VOCs. It’s about all of these other things. And there’s not really anything special about hot, humid climates that would make it so that all of those other things have lower concentrations.

45:29 Paul: What I really recommend people do is recognize that within the standard, you have options. You can do supply only; you can do exhaust only; you can do balanced and when you have balance, you can do with heat recovery or enthalpy recovery, so you get the moisture transfer as well, and because there are options then you can be smart. Look at the design of your home that you’re working with, and think about what would be the best system for this home to be able to deal with the levels of contaminants, of other types of contaminants that we see, while minimizing the impact on moisture. Certainly, there’s going to be homes where you have to do some dehumidification and I wish that wasn’t the case. I would like to say that’s not the case but if I tried to say that, a lot of people would tell me I’m lying and I would be lying if that’s what I said. It’s true.

46:24 Paul: There will be times when there will have to be some additional dehumidification, but we can. Though we wanna minimize how much dehumidification we do, we can deal with moisture in other ways, whereas we can’t really deal with many of these other contaminants in ways other than ventilation or not bring them into the home in the first place. I think we’ve gotta deal with those other contaminates, try to do it smart for the home you’ve got and then try to avoid having to do any other dehumidification through making smart choices.

46:58 Joe: I guess also, there’s an argument that you could make that, hey, if you wanna build your home on the coast in Miami, then adding some dehumidification is just something you’re going to have to live with.

47:10 Joe: Well, that’s true. I also feel like we can’t tell people, who don’t wanna dehumidify, that they have to leave their home and everything they’ve ever known. I do want to acknowledge that people are going to live there, and we need to do what we can to give them the best overall healthy home possible with ventilation being part of that.

47:39 Joe: Oh, yeah. Hey, John, let’s go to the round up here.


47:57 Joe: Alright. Let’s wrap it up. We’ve got about eight minutes or so left here. Cliff, I’d like to give you a shot. Any questions you’ve got for Paul for this last segment?

48:07 Cliff: No, I’m good Joe, thanks.

48:09 Joe: Alright, great. That gives me a little more time to go into a couple of other topics I was interested in, Paul. As far as the ventilation, I hear… Obviously as an indoor air quality guy, exhaust only ventilation has its issues. Because we don’t always know where where we’re drawing that air from. We’re getting that infiltration, we don’t know where it’s coming from and I’m wondering, is that something that you expect to see go away down the road or?

48:41 Paul: No, I don’t expect to see it go away. I think we have a number of different types of ventilation options and they each have their benefits and their drawbacks. So, I don’t expect any one option to go away. What I do hope is that we gradually are able to give improved guidance on when to use what. For example, with exhaust only ventilation, if you put that into the rooms that generate the most contaminants through either just storage of products or people’s activities, then that exhaust ventilation is getting rid of the bad stuff right away before it can get distributed throughout the house and then you’re absolutely right, you don’t know where the air is coming from, the make up air, so it becomes important to try to air seal between the house and those spaces such as crawl spaces where you don’t wanna bring the air from.

49:32 Paul: Supply ventilation, you do know where the air is coming from, it’s coming from outside. If the outside air has a high particulate load, then you might need… You should do some filtration. It’s just good practice to do filtration in general. So in that case you do know where the air is coming from, but you are not getting rid of the contaminants at their source. So, there’s pluses and minuses both ways there. When you get into balance and you can extract from the rooms where the contaminants are generated and supplied to the rooms, to the rest of the rooms where you know where the ventilation air is coming from, that can be the gold standard. Big issue there is, especially in existing homes it can be very expensive to implement. And when you have leakier homes, it doesn’t tend to matter as much. The balance ventilation, I think, really makes a huge amount of sense in tight homes. But in leakier homes it’s a little harder to justify and then you have this trade off between getting rid of the bad stuff before it distributes throughout the house versus bringing in air from a place that you know.

50:49 Joe: Alright, I appreciate that. I think that’s very interesting. So, you don’t see that happening. What other changes do you see at least being considered for future versions of 62.2?

51:03 Paul: One thing we’re going to be having to do and we’ve got a working group on this right now, is really improve the multi-family section. As I said earlier, we got all the multi-family from 62.1, but until it was in our scope, we couldn’t really do anything about it. So now it’s in our scope and it’s gonna be just exceedingly important for us to improve our requirements for multi-family to work better in that sector. And so we’ve got a working group on that and we’re hoping to have some pretty significant changes there in the 2019 edition. Another thing, if we look long-term that I see us trying to do is, especially as we get better knowledge of what contaminants are in homes at what levels in current construction, is I can really see us getting into a method where we focus it on specific contaminants. Right now it’s just overall ventilation.

52:00 Paul: We’ve got a little bit on particles, but other than that, there’s nothing where we’re calling out a specific contaminant. So I could really see us starting to tailor it to different situations. And then one other one I’ll mention, I know you only have a couple more minutes, is smart ventilation controls where instead of ventilating continuously, regardless of whether anybody is home or regardless of what the weather is, modifying the ventilation to account for things like, how much infiltration are you getting because of stack effect and the outdoor temperature? Is nobody home? And having that be automated so that you can reduce the ventilation when it’s not needed as much. I think that would help to get adoption and acceptance because I know people are worried about how much they might be spending given that they’re often times not even there.

52:50 Joe: Well, it’s like you’re reading my mind here because that’s my next question. Ventilation costs money. How does the committee balance that cost of ventilation versus the benefits of ventilation? Is there a formula for that? We know that ventilation helps with indoor environmental quality issues and maybe with health and so on. How does the committee balance that?

53:13 Paul: Oh, the committee doesn’t. Every time that topic gets brought up, people on the committee remind the rest of the committee that we’re a IAQ standard not an energy standard and the energy part is not our requirement, our role, and that’s really the role of other committees. So, the committee itself doesn’t really look at it. I will say that if you have high efficiency fans… But the calculations I’ve done have suggested in a place like Chicago just north of me, you can have a 50 CFM fan running continuously for the year and it costs you about 50 bucks in energy. So I think the energy impacts are not as huge as a lot of people think they are. Doesn’t mean it’s negligible and it’s gonna depend on the type of system you’ve got, but we justify that by the fact we can have tighter homes and the fact that there are health benefits as well. It may be harder to value those monetarily, but they are real.

54:15 Joe: And before we go Paul, we always like to give you the last word. Is there anything… But before I do that, let me just thank you personally. I know how it is to volunteer on these committees and it’s just a tremendous undertaking and I for one appreciate the time and effort you and the others on the committee have put in. I don’t know how often people tell you that but I wanna make sure I say that before we go to the end here. And before we do end, is there anything you would like to add before we go?

54:48 Paul: Well, thanks very much, Joe. I really appreciate that. I guess the one thing I’d like to add is this is not a very easy, simple thing. It’s complex because different people in different homes respond differently to things. And I would like to suggest that people take a little time to try to understand this and try to understand their own homes and the role that ventilation and other things have. And don’t assume that everything is just one size fits all or that requirements are there to make trouble, that we really are trying to help with things and it’s kind of a young but quickly evolving science. So expect things to keep changing and check back with us.

55:35 Joe: And hopefully we’ll be able to get you to check back with us Paul. This has been a really excellent interview. We really appreciate you joining us and hopefully we’ll talk again in the future.