Designing Multi-Purpose Roofs

[Shane Clarke] Kia ora, tēnā koutou. My name is Shane Clark. I am the general manager here at Nuralite, so the professional MC, amateur GM here at Nuralite. For those of you who don't know, Nuralite's been synonymous with flat roofing, waterproofing for about the last 50 years here in New Zealand. So we specialise in flat roofing, waterproofing roofs, obviously, and below ground. So yeah, welcome to our 24th webinar in our series, Online Education. I'd like to introduce my panellist here, Lewis Olding. Good morning. He's our product manager for Nurajacks. And today we're just going to kick back and forth a bit of a topic around design solutions and considerations for multi-purpose roof areas. We also want to provide some, I guess, inspiration and some confidence around what you can do with your roof. Not to be too shy about what you can do with your roof, make use of these spaces and do it in a good way. You've got a good outcome for everybody. So this webinar is NZIA accredited. So for those of you who are NZIA members, there will be a form at the end of it where you can chuck your registration in. All our past webinars are also accredited for NZIA. And they're all available on our website. Our webinar layout, if you like, we speak for about 20 minutes. We'll touch on this topic. We're going to touch on three points, basically, just considerations around making use of this roof space. And then we've got about 10 minutes towards the end for the Q&A. So Lewis, we do a charity as well. So you're going to introduce our charity. [Lewis Olding] Our charity is Movember this year. So because I can't grow a moat, that's why we've got cutouts. We're really proud to be supporting Movember this year. So $10 from every attendee will be sent off to Movember to help with that wonderful cause. [Shane Clarke] So thanks for attending, everybody. You already made the world a better place. Thanks very much. Right. So we want to make this as interactive as possible. Otherwise, you get to sit looking at talking heads for half an hour. So we'll try and make it a bit interactive. So the Q&A function is live. So if you've got any questions, pop them in and towards the end, we'll try and get around a few. So that will be the last few minutes of the webinar. So to help warm up those fingers on the keyboard, we're going to run a poll. So the first poll this morning is basically how many webinars have you already seen out of our series? So we'll leave that run for a minute or so. What have you seen? I think I posted all but one or two. Really? Yes. For you. Sorry. All right. Thank you, Jade. Excellent. All right. Well, let's kick into it. Let's talk about roofs and when you're no longer a roof. [Lewis Olding] Yeah, when is a roof not a roof? Yeah, that's a good question. If we go to those slides there, Jade, thank you. So a roof is not a roof, really, when it's a multi-purpose surface. So when we're talking about decks, a trafficable surface, well, that's generally a deck, a roof turns into a deck, doesn't it? When we talk about green roofs, well, it's aesthetically pleasing or have some other elements to it. That's another option. The roofs now are becoming functional surfaces for other things like solar panels. And so that involves complications about fixing and things like that. We're going to cover up just some of the challenges on each one of these types of roofs. And it's going to be pretty rapid fire, but try and get some design principles in your mind for when you're designing these sorts of spaces. [Shane Clarke] Yes. So overall, these are probably some really big topics. This is really just a quick brush through. And like I said, just to basically let you know that there are solutions for your wonderful design ideas and where to get those ideas from. So the next slide there. Right, so I guess first and foremost, the roof has a purpose, doesn't it? [Lewis Olding] Yeah, the roof has the purpose of protecting the building under it. [Shane Clarke] Yeah. A lot of people forget about it. We sometimes call it the fifth facade or the forgotten wall. [Lewis Olding] So the waterproofing or the membrane or the actual roof is the most important consideration. Yeah. So that's where we need to start in the design process, is actually start from the roof up. And because historically, there have been challenges around tropical surface on roofs. When we think of the leaky home syndrome, glued down tile beds was a big thing. And that caused a whole lot of dramas for selection of waterproofing and detailing. Even today, detailing is still one of the critical things that must be considered in any design. [Shane Clarke] Yeah. And I think when it comes back to that detailing, if you can liaise with your chosen membrane supplier, they're probably the first protocol that's going to give you the best advice. Unfortunately, we have seen errors like adhering tiles directly to membranes. Yeah. Terrible detailing, nailing through membranes to hold, you know, literally that happens. So let's not do that. [Lewis Olding] There are much better solutions. Yeah. So the question is, how do we protect the membrane or protect the roof? Yeah. So we're going to touch on the first one that we want to highlight really, the trafficable roof. We need to consider using pedestals because that becomes the standard for protecting roofs for a tropical surface. So when we think of a pedestal like the Nurajack, it's important that they can handle the load that you're going to apply to them. So the Nurajack, for example, can handle a thousand Kgs each and it distributes that load over the waterproof membrane so much so that we guarantee not to damage the waterproof membrane. The head's self-level. So that means that if the waterproofing has a fall, which they all do, the head will find its own level, guaranteeing that the full surface of the jack is supporting over that membrane to spread the load across the membrane. There's other features that we can go into in the Nurajack and there's other webinars actually about it. Another thing around that is actually the accessories that are available within the system, because with any system, whether it's a timber deck or a tile deck, they all require accessories. So having the availability, but also a range of accessories to complete the whole system. [Shane Clarke] So what I particularly like about the Nurajack is that it allows the water to flow out and that's what we're seeing here in this detail. [Lewis Olding] So just going back into that detailing again, making sure quality detailing in your drawings is very important from an installer's point of view or the constructors point of view. They need to know how the system is going to work when it's being built, obviously. So this detail is just one example of good detailing. It's showing a scupper running to an outlet and you can see that the scupper is actually being recessed or rebated into the substrate and there's multiple layers of membrane in that area. That sort of detailing is critical for it to be successful. [Shane Clarke] Yeah, I do want to point out on that particular detail I quite like is that the CodeMark logo here makes life a lot easier, that's for sure. OK, and we've got the next slide. [Lewis Olding] So we're going to move on because we are short on time on this one and we said it would be rapid fire. Green roofs are another option as a multi-use service, right? And so what's going on here Shane, with this code? [Shane Clarke] Yeah, so I mean with the green roof obviously first and foremost it provides a wonderful aesthetic, you know, that looks fantastic. It helps create biodiversity, it supports plant life and bug life and bee life, you know, so it's really good for the ecology. The other benefit of a green roof, of course we're just running over the surface of this, is the fact that it retains stormwater. So it is sort of noted that a green roof will retain about 80% of the stormwater, so you've only got about 20% of that water running for waste. [Lewis Olding] Does that mean, like, so when thinking of it from a design point of view you need to actually start considering the structural integrity of the building because the added weight that's going to build up on it on a green roof? [Shane Clarke] Yeah, so I guess an extensive green roof could add sort of up to five to six hundred kilos because you've got to obviously calculate the saturated weight per square metre. So what we want to point out in this particular build up is the Nuralite green roof drainage map. So what we're seeing here in this image is a 25 mil deep grid, if you like, not quite an eggshell because it's square, I haven't seen square eggs, but the idea is behind this, this little reservoir fills up with water and that acts as a irrigation system for the green roof above and then what happens is if it continues to rain and that water will then overflow right onto the membrane and then the membrane will do what it does. [Lewis Olding] So what size are these and where are they fitting the build up? [Shane Clarke] Yeah, good point, just flip back one slide, Jade. So basically the Nuramat green drainsits in between the growing medium, we don't call it dirt, between the growing medium and the membrane. The membrane itself is a particular specification for green roofs, they have an anti-root inhibitor built into it just to promote, again, just the longevity. One of the other advantages of having a loose laid drainage map like this is if for some reason you need to maintain the roof here, you can actually pick it up, move it around and put it back again. [Lewis Olding] Yeah, and so from a membrane point of view, what membrane would be on this job? [Shane Clarke] Yeah, so sorry, this would be Nuraply 3PG and I think there's one other little advantage from a membrane suppliers perspective that we like about these ballasted or green roofs, these covered roofs, that the fact that the membrane will never see the light of day, therefore it's protected from the UV, giving you a lot longer life span, so I quite like that idea. [Lewis Olding] They've also got that root inhibitor in there, so it stops the roots potentially damaging the membrane. That's right. So again, just really stressing, thinking about these things well ahead of time and getting your waterproofing supplier involved to be able to detail properly and then get the right products installed will make the job run a lot smoother. Another option to green roofs is a planter box and we see this a lot more when it's multi-use and there's some key advantages with a planter box to consider. We do get asked quite a bit, do we integrate the planter box into the waterproofing, into the structure of the building and that sort of thing? Well, because the Nurajacks can handle 1000 kg each, it's actually quite good to be able to put the planter boxes on Nurajacks and like we have in the detailed drawing here to the left, we see that the Nurajacks are just supporting a concrete planter box, so that enables the membrane still to be accessible if necessary and the air and water to flow around the whole system and the amount of Nurajacks that you would use in that scenario is depending on the load that you want to carry and distribute. So have a look at your calculations, get in touch with us if you need assistance in that decision. [Shane Clarke] I guess the other advantage of using these planter box type scenarios is that, like I said earlier, the green roof is quite a lot of weight and if we're using a planter box scenario, we may be able to centre these planter box over structure to take the weight, also provide flexibility should the tenancy change and they might decide they want to put a tennis court up there or something. [Lewis Olding] Yeah, or move, if a new tenant comes in, they can move the planter box. We've even seen planter boxes actually on cast wheels on top of floated tile decks and then they just move them around depending on what the building occupier wants. Yeah, right. So another consideration actually in these sorts of forms is with regards to what happens when the wind blows. So just personal experience, lived in an apartment on the 10th floor and we had a wicked, like almost cyclone blow through and the top of our table blew off and smashed against our glass doors, our sliding doors. So wind uplift happens on buildings, right? It's a known fact. The higher you build, the more chance that's going to happen. So what considerations do we have around plying things down, holding things down? It's such a critical part. [Shane Clarke] Yeah, so we put all these things on the roof, that's great and we want to make them stay there, right? [Lewis Olding] That's it, that's it. So there's been a bit of talk in the industry about tiles, if we're doing floated tiles, what's the need for these sorts of things. In New Zealand, the chance of this happening is actually quite low. However, this is where an and so we have a solution which is the Nurajack Windproof. It can hold tiles down to the tops of the jets using this system and that will withstand about a 2.1 kPa uplift and which is more than enough for the majority of New Zealanders. [Shane Clarke] Yeah, I mean we are starting to see these one in 100 year events happening every 10 years now. Good to have a solution to put it all together. [Lewis Olding] Yeah, so the point is again, and this is what we're really stressing within this webinar, is thinking about these things in the design stages, perhaps later in the construction stage with these last minute decisions to try and overcome some of these challenges. So knowing about these products being available will help. [Shane Clarke] Yeah, and give you confidence to actually use that flat space. [Lewis Olding] What if you've got a timber deck or another sort of project that you need to tie down, what would you use? [Shane Clarke] Yeah, sure. Just flip to the next slide. What we're looking at there is the Nurajack fixing plate. Now this is a structural fixing plate. I'll show you in the next slide. Sorry, Dave, let's go back to the previous one. So yeah, it's a structural fixing plate and it's factory assembled. So basically the membrane skirt, if you like, is installed in the factory. The plate's then taken to site, it's then installed. This will give us a wind uplift rating per plate of about 5 kPa, depending on what fixings we're fixing into. So if we need higher than that, obviously we use more plates. Also has a loading of around 5 kPa as well. So it's not uncommon to see these used in conjunction with Nurajacks. So they're at the timber deck, for example, on top of a rooftop where basically there's one of these in each corner and they're using the Nurajacks to resist the downward load and they're using these to resist the uplift load and keep it all in place. So these are all part of the Nurajack system as you like. So we see a 3D render in the next slide. [Lewis Olding] Simplicity of waterproofing and that's a key consideration is anytime you've got a junction or a penetration through the roofing structure, addressing the waterproofing, how that works around that is critical and it's complicated sometimes. And so having a factory system. [Shane Clarke] Also very quick to instal. I mean in the good old bad days, this here replaces the 4x2 screwed down to the membrane and then relying on an applicator to dress around it with two layers of membrane, which is quite slow and tedious. The other thing with this fixing plate as well, which you can see those blue flanges, it allows us to use them in the warmer build-up, eliminating potential thermal bridging. [Lewis Olding] And so when you've got things like solar arrays, which as we all know are getting very popular, we even want to have them on our roof, don't we? You've got to charge your solar car. Electric car. So again, thinking ahead of time, how this is going to affect the rooftop area and wind load and other penetrations, those sorts of things. And that's where, like we have the illustration on the left hand side there, we have all those fixing plates there holding the rails down, which then have the solar panels on. [Shane Clarke] I particularly like this example by Seng Architects. It's in Piha, so a very, very windy area. Those of you who know the area, very windy. And this building was actually retrofitted on a membrane. So this just shows the scope in which we can use these roof spaces. Very good. All right. OK, back to some projects now. We're about two minutes to go on this, then we'll run into the Q&A. We've run through some projects now, basically, and give you some inspiration. [Lewis Olding] Yeah, when we raised this idea of this webinar, we thought it would be great to talk about and then we realised how deep the dive would have to go into it. And so looking at some existing projects helps us to sort of see the potential of those roof areas. So this is that Grace Apartments that we've already seen one of the illustrations there. It's a multi-storey building with a rooftop. It's a beautiful area where all the tenants can use. Just like a shared space. And you can see that it's actually sitting on an outdoor composite deck, which is supported by Nurajacks. And then we have these screen roof elements for it as well. But as we go down the building, the next slide, we've got the balconies around the perimeter. Now, they were all just pavers directly on Nurajacks. We, that's the most common design for your standard balconies. There's no, when they're behind a balustrade like that, very little wind uplift, very little chance of those sorts of things. So our standard detailing was used around there. [Shane Clarke] OK, so just the standard detailing because this building is in Union Street in the CBD, up the top of the Red Sea, so it's quite a high wind zone. [Lewis Olding] Extremely high wind zone. Standard 20mm files on Nurajacks work fine. [Shane Clarke] OK, got another project here, France Street. [Lewis Olding] Yeah, so France Street Apartments, it's a beautiful podium area on top of, I think it's a seven storey area there, large area of, and if we go to the next slide, actually, we see a massive area there where such a communal, again, communal area. And it's got this beautiful, all of it supported on Nurajacks, got beautiful pavers that were supplied by Horizon International, contracts that the instal workers job, and all the precast and prefab elements were provided by Horizon International as well. It's such a beautiful space there, well designed by the architects and landscapers. [Shane Clarke] Yeah, I think this is a really good example of a mixed use space. So basically they've used every single element there, and in turn what would be a rather average looking podium area into something a bit more usable. [Lewis Olding] Yeah, yeah, it's definitely very, very beautiful. [Shane Clarke] And we have the Esplanade House. All right, so this was a residential house in Christchurch, I believe, where they've used, well we can't see in the zoom away, you know, the pull away photo, but those solar panels there are fixed and held down with the Nuralite fixing plates there. [Lewis Olding] Also had some beautiful timber deck areas, all supported. And so to note there, there's a spa pool on that timber deck. So Nurajack's, because they can handle a tonne of weight each, you can use this for spa pools, whether it's over a membrane deck or even just a little bit of concrete to level it up. And all you do in that area to protect the membrane. So again, thinking about, it's all about protecting the roof. It's increasing the quantities of Nurajack's to be able to distribute that load, because on a sparkle it's quite dynamic, water moves when people move, that sort of thing. So just increasing the quantity of Nurajack's in that area to protect the membrane. [Shane Clarke] And again, any water that spills over the side is going to wash away and run away. That's great. This is a really interesting example. This is definitely not like the school I went to. This is a school down in Christchurch where they've utilised the flat room space as part of the play area. Great example of using that extra space. The school's on a relatively small site anyway, so you can't quite see it in this image, but there is a bit of a playground and you can see the slide there that I don't fit down. [Lewis Olding] No, we actually have a full webinar just on this project. If you go back through either our YouTube channel or our website, Nuralite.co.nz, you've got our webinars. You'll see a deep dive into this project with Andrew Barry and the inspiration where it came from Japanese design and architecture, where he worked for a long time. So it's a really interesting webinar. It's worth looking into. So if you want a deep dive into how this was achieved, that's a 30 minute webinar. Nice. All right, we're 22 minutes in and we're getting to the good bit. Right. Rooftop bars. It's a place we probably all like to spend a bit of time. What a great way to have a multi-purpose roof, right? Just put a bar on it. And so Nuralite and Nurajacks have been involved in many of the rooftop bars around the city. [Shane Clarke] Quite an exciting experience. [Lewis Olding] Absolutely, absolutely. And so because this is possibly our last webinar of the year, we thought, well, for all those that have joined us today, we're going to just draw a random name out of all those that are here to be able to have $150 worth of rooftop bars, at QT bar, and you can buy that. [Shane Clarke] I'm just going to pull a name out of that. [Jade] So the winner is Patrice Turrell. [Lewis Olding] Patrice Turrell. [Shane Clarke] Excellent. Well done. Thank you. We'll be in touch. [Lewis Olding] We're going to send you a voucher. Well done. Thanks for joining us for our 23rd webinar. [Shane Clarke] Yeah. So, look, thanks again for your time. Hopefully we've given you a bit confidence around putting things on your roof, whether it be, you know, really nice aesthetic green rooms or simply plant care to actually handle the building. So hopefully we've highlighted some of the securities there for you. So I'm going to run through a couple of questions now. I've got a few coming. So by all means, send some more and we'll get through what we can. What we can't get through, we'll actually send out in a recording of the webinar along with a word document with all the questions. So I've got the first one here. Are the Nurajacks recyclable? [Lewis Olding] Yes, they are recyclable. They're polypropylene in construction. But what's really interesting about them is that they're made from 100 percent post-consumer recycled product. [Shane Clarke] So they're recycled before they're used? [Lewis Olding] Absolutely. So they actually come from recycled product. And that's made 200 kilometres from the factory. So we sort of know the whole build up of the. [Shane Clarke] OK, I'm sorry, just one thing I forgot to add earlier is that there's a lot more information available in our flat roof design guide. You can see that there. So we're going to drop that into the chat. So this is the volume 2. So you may have already got one. We've updated it. Volume 2 sort of covers a bit more of what we talked about and covers more roofs. Right. Can I put a spa pool on the Nurajacks? Yes, we can, is the answer. The green roof mat, is it travelable for maintenance? Yes, it is. The green roof mat has a compressor strength of around about 180 kPa. So you can walk on it. Not for regular traffic, but for maintenance traffic, i.e. weeding, irrigation, maintenance, things like that. It would be fine for that. [Lewis Olding] So with regards to the next question, is the roof mat for green roofs, storing cubes with the intention to reduce stormwater on the downstream system? That was the question. Basically, it acts as a main, I'd be right in saying the main reason for it is to actually offer some extra feeding to the plants. But the actual whole build up in the system does slow that water transference down. So what happens is as the water sits in that system, it can evaporate back out again, or it just slows down that transmission into the stormwater system. So as stormwater systems get older, of course, we know in Auckland here they tend to flood under heavy rain events. So a green roof can slow that down so that then it comes back into the stormwater system over a longer period of time, minimising those events. Is that the right answer? [Shane Clarke] Yeah, that's right. And there's actually some really clever people out there when it comes to green roofs who can actually calculate your specific green roof and what your stormwater retention component is, because they need to do that to actually calculate the saturated weight. [Lewis Olding] And so follow up questions just come through on that. Does it count as stormwater retention? Just contact us and we can talk you through that. [Shane Clarke] That can do. Yep, there's calculations for saturated weight. So yes, it can and we can give you some figures to throw into the calculator for that. A question about the Nurajacks here, Lewis. This is the smallest base. [Lewis Olding] I don't know if you can see that, but on the base of a Nurajack are some cut lines and the cut lines can bring the base down to around about 120 millimetres. So that means we can put the smallest cut tile that we can put on a Nurajack is around about 150 millimetres. So we can get those bases really cut like that. [Shane Clarke] OK, cool. I'm just going to run a quick poll, a second poll, throw that up there. Look, if you're just working on a project right now and you'd like someone to contact you, you can jump in and vote there. Sorry, it's got too many questions here. Right, just got one last question here. How long do Nurajacks last? [Lewis Olding] Oh, they're recyclable. We can warrant them for 20 years. [Shane Clarke] OK. [Lewis Olding] But they'll last a lot longer, of course. So you tend to find that what's on top of them gets replaced before the jacks do. [Shane Clarke] So yeah, that lasts a lot longer than the, you know, before the twos that we used to use in the bad old days. [Lewis Olding] Yeah, but this whole system is warranted for at least 20 years. [Shane Clarke] Right. All right, we're going to finish up with our third final poll, which is your chance to give us some feedback on future topics, actually. What's hot? What's not? We know what we know. You tell us what's of concern to you and then we'll put it into our education series next year. Awesome. Well, yeah, that concludes our 30 minutes. Thanks very much again for your attendance, making the world a better place for the people at Movember. We'll put those donations through on your behalf. Hopefully we've given you some inspiration and some confidence around designing multi-purpose roof areas. There's definitely a way to do it. Don't be sort of restricted by your imagination. Definitely a way to do it. [Lewis Olding] Reach out to the people that know. Whether, you know, here at Nuralite or wherever, reach out to people that know to help start with the design process first and then so they can be implemented successfully. [Shane Clarke] Awesome. All right. Thanks again, folks. Ka kite anō.