Tapered PIR Roof Design

Morning folks, we're just going to wait about 15, 20 seconds just while the room populates and just bear with us. Cheers. All right. Kia ora, tēnā tātou katoa. My name is Shane Clark, I'm the general manager here at Nuralite. Today we're going to talk to you about our tapered warm roof solution. On the panel with me today, I have Peter Mills, our technical advisor from Nuralite. Hey, Pete. Hey, how's it going? Good, buddy. I've also got Shane Mulvey from Rhino Waterproofing based in Queenstown. Rhino Waterproofing has been Nuralite applicators for over 10 years and are familiar with our tapered warm roof system, so we'll be touching base with him later on. Before I kick off, I just want to mention that we have the Passive Health Institute of New Zealand's Auckland chapter function here on the 27th of November at 3 PM. It's going to include a tour of Nuralite to show you through our operation, and there will also be a hands-on demonstration on what we call Outsulation, which involves putting insulation outside the structure. We'll send an invite to all of you in the chat function on this webinar. We'll try to keep this webinar as interactive as possible. If you have any questions, feel free to use the Q&A function, and towards the end, if we have time, we'll go through a few questions. Don't worry if we don't get through all the questions; we'll come back to you with all the answers in a written transcript so we won't leave anyone out. This presentation is worth five NZIA CPD points. There will be a survey that goes out automatically at the end of this week, and we'll populate your number. I think we're also sending out LBB certificates for those who require them. Today's topic is the Nuratherm tapered warm roof solution, and we think this message is relatively important to you as designers because we're trying to turn the totally impractical into the totally possible. Our key message today is that Nuralite offers a tapered roof resource that makes your complex roofs really simple. We'll run through a case study of a non-disclosed roof building we're working on. We'll show you what we started with, what we ended up with, and the massive cost savings. We'll then talk to Shane about the installation of the tapered warm roof from his perspective as an applicator to prove that it can be done, and share a few of his case studies. Before we kick off with Peter, I'm going to run a quick poll. Are you familiar with the warm roof concept? This will help us understand who's in the room and how to best pitch our message. All right, it's good to know we're starting at a relatively high bar. Nice to see that the message of the warmer effects is getting out there. Let's kick off into our first slide. Peter, can you explain what we're looking at here? What's tapered insulation and what's PIR? Sure. PIR is a polyiso board or polyisocyanurate. Tapered PIR is a version of that insulation that has a slope built into it from when it comes out of the factory. What you're looking at here is an exaggerated render of one of our tapered PIR boards. Our tapered PIR boards come at one degree. The objective of this product is to create a compliant roof fall just with the insulation. And being made in a factory, it's consistent and accurate? Yes, they have machines that ensure it's always one degree and the correct thickness. So, in the slides later on, the plans we produce can be carried out correctly. Okay, cool. That was the first building block in the process. Now, Peter will explain what we're doing here with the additional blocks. With our tapered PIR boards, we have four sizes: A, B, C, and D. The A board ranges from 40 millimeters to 60 millimeters, B from 60 to 80, C from 80 to 100, and D from 100 to 120. We use these four boards, as well as flat boards, to achieve the roof falls laid out in the plans we produce. Nice. What are we seeing here, Pete? We've got two example substrates, concrete and CLT, with tapered PIR on top of them. You'll see the four ABCD boards on both substrates, and then an 80mm flat board underneath the last two columns. This 80mm flat board is what we use to restart. So, we go A, B, C, D, A plus 80, B plus 80, etc. We keep doing that as much as needed. So, we don’t have to start with an A board. Could we start with a C board, for example? Yes, we can start at virtually any thickness above 40 millimeters. We can start at a B board between 60 and 80, or if the job requires it, we could start at 140, which would be a B board plus 80, just for a wild example. Excellent. Now, Peter will explain how we create the fall. When we're asked to create a tapered plan, we need two things from the designer. First, a simple checklist that tells us the roof requirements, such as the target R value and any restricting parapet height. Second, a roof plan clearly indicating the area to be tapered and where the outlets or gutters are, with at least one dimension on the plan. What you're looking at here is a roof plan overlaid with the plan we produce. We've used the provided information to create a clear layout of the A, B, C, D, and A plus 80 boards. Can you show the low points and high points? Sure. The low points are the scupper outlets, and the roof falls towards these points. The ridgeline is the peak of the roof, falling from A plus 80 down through D, C, B, and A towards the outlet. This ensures compliance. Nice. If you're considering a tapered design, we'll pop an example of the tapered check sheet in the chat function. It's simple to fill out. Pete, is there a roof plan outline? Yes, the check sheet includes an example roof plan. We need a roof with a dimension, clarity around the area to be mapped, and clarity around the low points. Other points in the checklist include the desired R value and the minimum start height. We're about to take a deep dive into a non-disclosed roof in Auckland. We'll compare two roof plans, A and B. Pete, can you tell us what we're seeing here? In plan A, the tapered PIR boards are applied like a traditional membrane roof, with gutters around the entire roof. Flat PIR boards are added, and we start with the highest point of the gutter. The tapered PIR boards are doubled to achieve a two-degree roof, starting at 120mm and reaching 620mm at the max. This uses about 468 cubic meters of PIR. To give you an idea of volume, a 40-foot high cube container is just over 70 cubic meters. So, several containers are required for this thousand square meter roof, adding to the cost. There was a target R value for this roof that we massively overshot. Our rule of thumb is that if the R value hits double digits, there's room to improve the design. What did you come up with, Pete? We looked at the riser locations and geometrically mapped out the roof. We added sump locations over the risers. Can you indicate the sumps and ridges? Sure. Here are the sumps, and we work out from 45 degrees from there. We have peaks, valleys, and ridges. Instead of starting at 120mm, we start at 80mm and work up from there. We start at C and reach a height of about 260mm. This uses about 180 cubic meters of PIR, saving around $270,000 in installation costs. Shane, any thoughts on the labor involved? It makes my life easier. It can reduce the need for tenting areas and speed up installs. Storage can also be an issue, so anything to scale back and make things easier is appreciated. The cost saving doesn't include the time and money involved in creating the screed to falls in the gutter areas, which would be in excess of three weeks of program waiting for concrete to cure. We've highlighted that we can improve the layout. We call it the waffle roof. Pete, did we hit the required R value? Yes, the required R value was 7.2, and we achieved 7.17. The remainder is made up with the concrete substrate. Good case study. Shane, any fun facts? I'm a stand-up comedian with gigs in Wellington, Napier, and Palmerston North next week. Rhino Waterproofing has been Nuralite applicators for 10 years. Shane will share his experience with the tapered warm roof. We've been installing tapered systems for close to 10 years. The design has advanced and simplified. We can accurately price jobs and foresee any issues. On more complex designs, we advise tenting to minimize moisture ingress. Any restraints with adhesives? Yes, weather can be unpredictable. We prefer mechanical fixings to avoid moisture issues. Mechanical fixings provide ease and speed of installation. They also allow for future rebuilding if needed. If there's an issue with a glued system, it's difficult to remove. With mechanical fixings, it's easier to replace and maintain thermal value. Any particular case study to mention? This roof was challenging because they refused to tent us. We operated on about 100 squares a day, ensuring it was fully encapsulated in a base layer of membrane each day. Important to remember for architects: tenting adds cost but speeds up progress. A tented building site benefits all trades. Another case study: a flat build-up to gutters, tented area, large team, fast install, fully ballasted area. If cost is a concern, tapered insulation boards can be cheaper than creating falls on top of CLT panels. We installed the tapered system quickly, saving money on below-grade insulation. Other uses: Home Ground or Auckland City Mission building, warm roof on metal tray, tapered PIR board on decks and balconies. Time for a few questions. First question: the board is manufactured at one degree, but the council asks for two degrees. How do you get around that? For both Nuraply 3PM and Nuraply TPO, we have code mark certificates allowing compliance at 1 in 80, which is 0.73 of a degree. With our 1 in 60, or 1 degree tapered board, we overshoot that minimum requirement. Shane, can't we just put the fall in the substrate? We could, but it can be quicker to install a tapered system. It saves time and cost. Weight can also be a consideration. Screed may not be an option due to weight. Would you normally use a tapered board on a metal tray substrate? The preference is to put the fall in the substrate, but there are exceptions. Environmental credentials of the PIR board will be included in the follow-up email. Do we have to worry about the thin bits having a lesser R value? We take the average R value of the entire roof. If there's concern about interstitial condensation, we can carry out an indicative hygrothermal analysis. What was used for making the PIR trafficable on balconies? The PIR board has a compressive strength of 175 kPa. We use our Nurajack system to hold up a floating timber deck. For plant rooms, we can use a walkway sheet or add a cover board. Is this system suitable with TPO? Yes, we've developed a suite of details for TPO and have a code mark certificate for compliance. Shane, what's your preferred membrane, 3PM or TPO on a tapered warm roof? I love 3PM. It's a faster install and provides the security of two layers. There's no silver bullet. It depends on the type of building and location. We'll put unanswered questions into a Q&A document in the follow-up email. Join us for our next webinar on TPO and its CodeMark certification. Thanks to the panelists. Good luck in Wellington, Shane. Thanks, Peter. Enjoy your holiday in Europe. The recording will be sent out. Feel free to reach out to us. Thanks a lot, guys. Cheers. Let me know if you need any further assistance!