Passive House Multi Family: Best Practices and Lessons Learned

Our June Construction Tech Episode explored the intersection of construction technology and sustainable housing solutions. We were joined by NEI Boston, a leading player in the affordable housing sector, as they share their valuable insights and experiences in implementing successful Passive House projects.

NEI Boston is known for their unwavering commitment to affordable housing. With their vast expertise in a wide range of projects, including ground-up constructions, moderate rehabilitation, elderly housing, veteran housing, historic rehabilitation, and tax credit initiatives, NEI Boston has established itself as a trusted partner in the Northeast, Southeast, and Southwest regions of the United States. During this event, Jessica Morrissey and Chris Burke dove into the lessons they have learned throughout their Passive House journey and the subsequent best practices they have implemented to ensure the success of their projects. They share practical insights into incorporating innovative construction technologies to create sustainable and affordable housing solutions.

Transcript below.

Jessica Morrissey: Welcome, everyone. We really appreciate you coming here as they already did a great job introducing us so we won't spend a ton of time on this slide a little bit about NEI. Chris and I are based here in Randolph, Massachusetts which is home base. And but for Boston operations. We also have offices in Florida and Texas a little bit more about us.

These are some of the Passive House projects that are either completed, almost completed or in construction now. We have about 10 Passive House projects in the pipeline. So, these are just as you know, the four on the screen are representative small sampling of them. And throughout our office we have 19 certified Passive House builders throughout all you know varying positions from you know pre-construction through field and project management staff.

So today we wanted to talk about I guess myths of Passive House construction depending on how familiar you are you are with it. It can seem like a potentially daunting task to achieve. So I think some of it is so some of the things we're talking about is you know, subcontractors, materials, availability and cost and construction duration and what implications do those really have on your projects when you decide to implement Passive House construction? You'll probably notice this picture in our preview picture. The first slide, you might all recognize that building which is in Cambridge, it's the Finch, which Chris was lucky enough to work on. And I think one of the first Massachusetts passes so certify how certified projects. So I'll give Chris a little runway here to talk about some of these myths.

Chris Murray: So welcome, everyone. Thanks for having us. So sticking with the Finch, right, that was one of the first we'll buy families in Massachusetts and with that come starting the process ground up with everybody. Subcontractors obviously hadn't seen Passive House, maybe heard of it and passing they're used to dealing with lead things like that. So, you know, getting everybody on the same page and understanding you know, the importance of them. Being the trades being the masters of their trades and US facilitating their work and getting everybody organized. It took a lot of collaboration, pre planning, things like that and looking through different materials that that work. So, you know, we started this process early. We partnered up with a design team we partnered up with our subs. And you know, we held different meetings at different times to talk through that current milestone, and you know, ultimately looking at different products. So, you know, originally we started with a certain ABB then we switched to another one and through that we learned that they had different tapes and things like that different wraps that allowed us more flexibility. For those of you that don't know fish, Cambridge is a six story building to two levels of podium, four levels of wood on top of it and originally didn't start off as a Passive House Project. And it was, you know, it was pre approved during the process. So working through all that was huge. So, again, subcontractors getting their buy in making sure that were the details were feasible for them, looking at different products, talking to the talking to manufacturers, having them come out and work through it with us, and then doing live mock ups and you know at different stages of the project because obviously it's we need to hit stride schedule wise but we also need to make sure we're able to achieve the details and I think that's probably one of the most important things that details me Passive House and we can get we can get the trades to where they need to be.

Jessica: So talking a little bit more about the process. You know, I guess you have the kind of the book ends here of pre construction through construction with me, Chris. pre construction, we really spend time with the owners and the design team to define the project design. How do we get the design that our owner and architect are looking for the Passive House requirements and meet meet a budget. So when we're lucky enough to to work on a project from conceptual stages through construction, it's really you know, quite a great process because we can really review price, get some feedback and repeat as needed, but then we can kind of identify challenges early in the process. I think we all know sometimes everything works on paper and then Chris gets in the field and it doesn't and that's what makes him and his team so good at what they do. But when we try to you know, do head for him is you know, where have we you know, learn taking lessons that we learned from other projects or researching other products if something is not going to work either in the Passive House model or the budgetary model. I mean, I think that that's something that we all know comes into play. So we want to make sure that a package as a whole kind of gets to where we need to be and it's really it's a lot of collaboration we like to be involved not just at like the designated milestones of schematic design, development and construction but all the little bits in between because I think we all know that there are a lot of different pieces and parts to construction and the domino effect of changing one thing here affects something else there. And so you're really again, back to that collaboration of, you know, oh, here's a product that might work and now we're gonna go to the energy consultants and make sure that there's not a ripple effect. And if it works, that's great. You're gonna pat ourselves on the back and move on to the next piece of the puzzle, but it's um, it's really, you know, a collaborative and you know, process between all of us and then that's that just we'd like to tee it up as best we can to hand over to Chris and his team so that when they get boots on the ground and start going vertical or actually Passive House starts at the foundation. Jump ahead to go on vertical, but the the things are, are planned out as best as possible. I mean, there's gonna be hiccups and that's how we learn more is occasionally is when there's more, you know, data to go from so the more we do, the better we can refine the process also. So some of the things we do to make it work through the process is…

Chris: So going back to what Jess was just saying, you know, a big part of it is taking it and chunk, right you have your milestones you want to hit. We know what we need to do to get there. You could easily get lost in the sauce with you know, having a global conversation about the entire project. But if you're coming out of the ground, you're dealing with the foundation getting ready for steel, get ready for wood, you don't necessarily need to be talking about you know, drywall and compartmentalization. At that point in time. We need to be working through the foundation and then get to you know, pre rock and insulation and things like that so you know we would meet we would get with our trades and say okay, this aspect of the of the job is gonna require we need the framer here we need the sign or here we need the you know, whoever whoever owns the exterior envelope I should say sign or Fitch Cambridge It was decided in the Windows The ABB and deciding right so we would have them come in look at different intersections. Same time we're dealing with steel on the first floor and the concrete you know, making sure that we had the AVB tied in at that level. Once we got through that part we'd we start to meet with the MEP trades and somebody like the HVAC contractor, we'd look at what we needed to do, the milestones we need to hit and how do we test that ductwork in sections so that we can move on to the next phase of the building and get ready to go. So we have our pre test. We'd have our inspections and realize that hey, we got to put up the the main trunk first cap that tested tested and then we could roll into tie in and into the units and then go back and start working on installation and get to that point and you know, literally just set milestones with the trades. We work we work through the details with them. They tell us where they could meet it when they couldn't and from there we go back to the drawing board and you know these meetings were all basically separate meetings from your typical construction meeting typical owners meeting so it worked out well. Again, I can't stress enough being proactive and subs are the masters of the trades. They do it every day. We you know, we go through the lifecycle of a project. We'll see certain trades at certain times. And then we'll see him again on the next project where they're finishing. You know whether it's the ductwork whether it's the concrete, they're doing that every day for their for the life of their career.

Jessica: Yeah, I think your point earlier about, you know, coordination and building to the details is such a huge important one, especially if you're in a region of the country or somewhere that isn't as familiar with Passive House, there might be this. Oh, I'm, you know, I'm nervous to do this. You know, I know but what are the implications I think you know, no, actually, yes, I'm saying I I'm gonna lose my shirt on this. But it's really just I think, like you said, they're, they're masters of their trades, right? You break it down. It's just you're building to the details. It's Yes, the details may have some extra steps.

Chris: My conversation actually happened with specific trade was a drywaller. And talking through it early on before the project started. And, you know, the, the immediate response from whether one of them was hey, I don't know Passive House was like, Okay, well, let's take a step back. You see any issues with the details? Now I should be able to do this. Maybe a couple things. Work that don't work. It's like alright, well, if all the details work, and you can build those you're building Passive House. And it was like, you know, they were you can see the sense of calm come over and it's like, Alright, I just gotta follow it. And then we started doing mock ups. We did you know, we had a mock up outside to get us as far as we could and Windows siding ABB and then we were doing in Unit mockups as well and again section without taking any chunk, hit milestones like we're gonna look at this we're gonna go with document and we see where issues were and how we had to get things moving and then we can apply it to the, you know, the next 100 unit or next 97 years ago. So it was a 90-unit project.

Jessica: Right. You have your baseline that you have set your reference point so that everyone can go back and refresh. Yes, they need to.

Chris: Lots of lots of paperwork to follow so that we can issue like here. Here's what we did in this unit. Apply this these all these units looks similar. Lay out these ones may be a little different so so let's look and make sure you don't have a problem there. Maybe we go into one unit and then you know, one different unit and see if there's any problems there and then we can tee that up for the following meeting yourself without…

Jessica: Yes, there's some extra meetings but I don't think that there's a huge correlation between an extensive you know, you know, additional duration on your construction schedule associated with those I mean, I think it's that's just proper planning. That, you know, probably any project could benefit on whether it's Passive House or not.

Chris: It’s never too early to start looking at it and market through it, right?

Jessica: Yeah. So some more lesson learned here. And this graphic that we have up is also from the finch right I believe so. This was I think probably a little bit was a because it wasn't intended to be Passive House from the start, but it also gave some real great, you know, learning and understanding of how to have these intersecting assemblies. I'll let Chris explain it a little bit more but so we wanted to put this up to kind of show how we, I guess broke this this little portion of the building down into some manageable bites for everyone and set this this like order of construction, you know, very specifically.

Chris: Again, since it started off as non Passive House and then was approved during the process and as you're looking at that graphic to the right is the first floor would be the first floor, leasing office area and then a space that was outside of the Passive House, the left was inside the Passive House and clearly you have steel on the exterior of the building. So this was an area I won't call it a challenge but it was an opportunity for us to work through the details of make sure it covered and that led to the rest. You know, it was a podium that you could park underneath so it was wide open on the ground. floor level. And then the Passive House started on the next floor up to the left outside of that image. So it just gave us a you know, this is a good example of something that we had to work through and, you know, make sure that we achieve what needed to happen there. And clearly we were successful.

Jessica: This one is we're just an example of you know, we had some success on a blower door test. But I think there are some sequencing of this testing that Chris already touched on a little bit. That is important to note that there is some midpoint lower door test results that should be done. To ensure that when you get to the end of the road that you're also going to have success.

Chris: A challenge with this similar to LEED is the test suite and get the final testing done at the end of the project. So we needed to come up with ways where we could turn around and get that comfort level. You know whether we're doing compartmentalization of the actual unit, doing the duck testing, and getting as far along as we could so that you know we hit the milestones that needed to happen one for our Passivhaus certification but also that we knew we weren't going to be opening things up. And you know, we changed our sequence a little bit. We introduced some third party help to come in and join us for a day and test things out. And I can't say enough how important that part was. We were able to keep moving forward and you know, wrap the building up and hit stride when we need to.

Jessica: Yeah, Holbrook is actually another project where you had field troubles not only you know, that's not always the case that we get to work out everything in pre construction. Sometimes we get into the project further along in the design, and it's pretty set in stone. And I think to get some of the compartmentalization between the units.

Chris: Yeah, there's some tricky details at Holbrook. But you know, same thing work with the architect work with new ecology and you know, we did some pre testing and things like that. Now made a couple of small changes to make it work and has just been looking at stuff being proactive and then applying it to where that that issue happened.

Jessica: So I do have a slide for this, but I'm not going to click to it yet, because I know I'm sure everyone is wanting to know, how much does this cost? What is the impact to my project? And so, I guess I'll say there are many factors that go into that. There's client project priorities, building design materials. We do a lot of affordable housing, so that there's there's some regulations, you know, the lenders and such that are required to implement that that could affect how the building is designed. So just the site specific, the site's perspective, what is your project site, and the building that you can put on it and the size of the building, you know, can all affect the Passive House bottom line, because some of those things might have implications on how you have to implement or how you have to create the details. And those details may cost more than a different way to do it. Which is, I guess the I guess somewhat of the beauty of Passive House I think, though, is that it is a little bit more prescriptive, and you can find different ways to achieve the same goal and sometimes it works and sometimes you have a site or a project constraint that just doesn't you know, help you in that fashion. But I think that's you know, one of the things I know pre construction that I find a fun challenge is getting projects to work out for everyone budgetary and getting over the line construction. So, punch line is we've calculated here, I guess in the northeast, mostly Boston and surrounding areas, about 2% of a cost increase directly relating to Passive House. Then some of those other items that we just mentioned, I just mentioned is could be five to 10% additional. So those all kind of go into the whole package, right? You look at different projects in different places and it's sometimes it's just your there's so many different variables. How do you really, truly pull out the exact cost?

So some other things to consider too when you're thinking about cost implication is where the Passive House envelope is, I guess kind of that picture we had up where there was an intersection of the two required a little bit more detailing how your exterior wall assembly is constructed. So again, that's something it we may go through a couple different iterations and pre construction of exterior wall assemblies to find the best one that meets the requirements of the project. Foundation installation and detailing depending on you know, what type and how deep your foundations are. Windows are always a good one, although I will say that there's been I guess, a few more manufacturers out there, I think two of them now have stateside production facilities, which is helping a little bit but I think there's a little bit more competitiveness we've seen in the market on those recently. And then similar to the Passive House envelope but how much exterior storefront or Passive House doors do you have within the intersection of the envelope. So those are all pieces, I guess of the recipe that goes into you know, construction of a building and getting it certified as Passive House. So with that, I guess we can open it up to questions. That is our last slide.