Innovative | with Dave Burggraaf, APL Senior Design Engineer

Dave sits with down Simon Farrell-Green, editor of HERE magazine, to talk about APL's innovative technology that keeps them ahead of Building Code requirements. Windows and doors play an important role in a building envelope, Dave explains the challenges that can bring, and what APL do in response to create products made specifically for New Zealand homes and buildings. 

00:00 Introduction  
00:37 Dave’s introduction  
01:14 About Dave’s team  
01:40 How much has the design of window frames changed in recent years?  
03:50 What’s changed in terms of what we can do with our windows?  
04:48 How does the building code play into that?  
05:42 What are the challenges?  
06:26 APL was ahead of the competition  
07:08 About APL’s ThermalHeart+  
07:57 How does APL make a window perform better and be more insulated?  
08:59 What does “a better-performing window” mean for homeowners?  
09:47 What does it mean for New Zealand as these systems improve?  
10:28 Better-performing windows and the H1 changes  
11:07 How do you design your products knowing that most New Zealand homes are stick-built?  
12:06 About Centrafix  
14:17 What about renovations?  
14:44 How do you design around that?  
15:13 Where do you see things going from here? what are you excited about?

🎙️ About the Series – Made here, for you
Made here, for you is a storytelling series by APL & AGP, shining a light on the people, places, and processes behind New Zealand-made windows and doors. Every episode captures the craft, care, and Kiwi ingenuity that make our products truly local and built to last.

🏠 Explore Our Brands
• Altherm Window Systems
• First Windows & Doors
• Vantage Windows & Doors

🌿 Proudly NZ-Made
From design to delivery, every window system is created here in Aotearoa supporting local manufacturing, innovation, and communities nationwide.

💬 Connect with Us
LinkedIn YouTube Instagram Facebook

Produced by APL. All rights reserved.
“Made here, for you” stories of New Zealand-made windows and doors, told by the people who bring them to life.

Chapters

• 0:00 Introduction
• 0:37 Dave’s introduction
• 1:14 About Dave’s team
• 1:40 How much has the design of window frames changed in recent years?
• 3:50 What’s changed in terms of what we can do with our windows?
• 4:48 How does the building code play into that?
• 5:42 What are the challenges?
• 6:26 APL was ahead of the competition
• 7:08 About APL’s ThermalHeart+
• 7:57 How does APL make a window perform better and be more insulated?
• 8:59 What does “a better-performing window” mean for homeowners?
• 9:47 What does it mean for New Zealand as these systems improve?
• 10:28 Better-performing windows and the H1 changes
• 11:07 How do you design your products knowing that most New Zealand homes are stick-built?
• 12:06 About Centrafix
• 14:17 What about renovations?
• 14:44 How do you design around that?
• 15:13 Where do you see things going from here? what are you excited about?

Transcript

0:00

Kia ora, I'm Simon Farrell Greene and I'm the editor of Hair Magazine. Welcome to New Zealand Made, a series of podcasts we're making with our friends at APL Window Solutions. The question we're asking is essentially, what does it mean to build or renovate in an increasingly global and interconnected world? And how do we balance a desire to reduce carbon emissions and improve the performance of our buildings with the ever-increasing cost of building? To answer this, we're chatting with experts about the latest developments in building tech and a few other issues as well. I'm joined now by Dave Bergraf, Senior Design Engineer at APL. Hi Dave. Thanks for joining us. So the opening question is tell us who you are, what you do and why you do it and you've got 50 words or less. Okay, right. So Dave Bergraf, Senior Design Engineer at APL. So I've been on the game a long time and that's all based around innovative product solutions, right? So I work with a team in Hamilton to come up with a new window-in-door solutions, improving old ones, bringing them along, but most importantly, the innovative aspect of what's next and how we get there. I think you might have actually done that 50 words or less. Yeah, might have impressed. Dave, tell us a bit about who you work with, who's the team? Yes, I work with a great bunch of guys in Hamilton at headquarters and they're all guys a little bit like me who have really well-experienced and collectively we've got 100 years of experience in this market with good feet on the ground experience, practical guys who know what's gone before, what's what hasn't and we pretty much know what's ahead and what to do and if we don't know we find out. Tell me, how much has the design of those frames changed in recent years? Quite a lot. And obviously it's driven by cones. So the cones these days are much tougher than they have been in terms of thermal performance, water performance, structural performance, durability aspects. So everything generally adds bulk and weight. So if I think back, I mean, if I think back right to the beginning when I started the frames are as thin as tin foil, they had a very simple job, single glazing, very lightweight products, sliding doors that weighed no more than 5 or 10 kilos, but now we find ourselves with double glazing, triple glazing, New Zealand codes which are pretty tough in a world since they're very tough based around weather performance. We have some pretty extreme weather events, seismic performance, we're in a unique part of the world, durability mainly because we're probably 95% coastal, whereas in mainland Europe or mainland China, very few sort of coastal cities. So a lot of their product doesn't really need to come up to scratch with that. So that's probably been the biggest change is just like how do we make our windows and doors more durable and better every time to keep meeting these really tough standards? And of course that's manifested itself in much broader sense of product range and also other capacities of the product and the performance codes they have to meet is just night and day compared to what it used to be. So the changes have been enormous. And that's at the same time I guess as our design ambitions have changed too, right? So you're having to have a frame that does more, but doesn't take up 20 centimetres on around the outside of every door and window. Yeah, exactly. House buildings fundamentally the same as it's always been, it's generally light stick framing, four inches for inch framing. And so yeah, we're quickly running out of room on the wall, space to do what we need to do, you know, with family performing joiner and performance codes and that. So yeah, we've got some real challenges there. Our houses aren't like European houses, we've got a unique way of building. So therefore, you know, our windows in Europe are about as relevant as their windows are here in terms of what they've got to fit into how they integrate with the building. So that's a real challenge to us is getting that performance and what's fundamentally still been a light stick frame type of construction for the last 100 years or longer. What's changed in terms of what we can do with them, you know, I'm thinking that things like heights and widths and spans and those sorts of things? Yeah, so in a back back again 40 years ago, when I joined the game, we worked in what was called block module size, was 200 ml because that was what a concrete block was and a big door was 2.1 metres, 100 ml bigger than a door, you know, really and 100 doors were single doors, sliding doors were single panels. And now we find ourselves like the architectures change enormously because if you go back to the, you know, the post-war building boom state houses, you know, a couple of casements on the side of a fixed window, a back door, a front door. But now, you know, the architecture these days is a whole lot more than that and we, you know, we enjoy the indoor outdoor lifestyle and so our windows and doors have got to reflect that. So it's really big heights, really big spans, massive opening doors and of course, that's a whole different game to what it used to be when we were making a back door in front door and, you know, five or six session windows for a house so it's come a long way. I thought we should just touch, you touched on it briefly before but we should just talk about changes to the building code around thermal performance. Can you, can you describe what that, what that means in a nutshell? So windows have to perform a lot better than they have done and we all know about double glazing, it's been around for a long time but the recent uses is obviously increased and uses double and triple glazing. So, you know, for performance codes and the increase in performance codes for windows is all about thermal efficiency pretty much and to do that we need to add things into the frame, obviously, double glazing, triple glazing, control air spaces, control air leaks, you know, all that sort of stuff. So a lot of technology's gone into window systems to suit what we need to do to meet the new performance codes. Because the H1 changes in the New Zealand building code is, as I understand it, is the total performance of the building, the thermal performance of the building. But obviously, as you referred to before, our windows and our doors are getting bigger. So they're a massive part of the thermal in the open. Yeah, yeah. So that's what's driven those changes. Yeah, you're very much like, you know, windows and doors have got a really hard job, right? They're part of the external element. The external element's got to be insulated, floor wall ceiling and windows have got a really tough gig and you've got to see through them, right? It's a right, if you're a piece of insulation, you can be as thick as you like and any sort of colour, but you know, walls of wall, windows are a whole different thing. We've got to be able to see through it, we've got to be able to walk through it, open and close again, ventilation through it. So it's a tough game, but, you know, without thermal break technology, now glass technology, we can meet, you know, really stringent thermal codes and more to come. You know, we've only just really started on the... You were already improving the system before those changes came in though, weren't you? Yeah, yeah, for sure. So we've been into thermal break window technology for around 20 years and double glazing goes back further. You know, the occurrence of double glazing in the 80s wasn't very strong at all. The 90s started to happen particularly down south, but it was a voluntary thing and then it about 2009, the code changed enough to make double glazing more prevalent. So we've been making thermally improved windows for a long time. So we've always met, you know, our values and exceeded our values, but with the latest changes to H1, that was another step, probably the largest step we've ever had. And if it steps again, we've got the technologies to meet that as well. So that's been thermal heart plus came in? Yep, for sure. So thermal heart plus was planned and it coincided with the changes to H1, so that was really good. So when you H1 was coming, we'd already had some thoughts about it, but it certainly showed the, you know, what our product would do, the performance that needed to have the size of the product, which dictates the weight of the product, the durability, all that sort of stuff. So yeah, we were ahead of H1, and H1 really confirmed our thinking about what we needed to do. Plus also building capacity into those windows and doors system. So things do get tougher from here. We're just a couple of steps away from it. Like, like, for example, you don't need to build a house with triple glazing, but our systems can take triple glazing today. So we had the same story with moving from single to double 20 years ago. It wasn't very common. Moving from double to triple is pretty easy for us now, because we've built in that capability within the product. Tell us about how you designed to improve a window. How do you make a window perform better and be more insulated? Right. So we use a thermal polyamide strip system for our thermal heart plus product range. And so we integrate those polyamide strips within the frame system, and that allows us to separate the outside part of the frame to the inside part of the frame. And crucially, in the middle, we can control the airspaces. So if you think about a piece of double glazing, it's two pieces of glass space, the part with an airspace, and the airspace is controlled as an insulator. And it's very much like the insulation and the water adjacent to the window. It's just pockets of controlled air. So our thermal heart system relies on the framing system being really good with thermal polyamide strips in it, controlled airspace. The area around the glass is controlled airspace. The glass itself is controlled airspace. So we put the whole system together plus an installation system to create this thermal improvement we need for the external part of the envelope. What does that mean for us as homeowners? What does that better performing window indoor mean? Yes, it means a better living environment inside the house. So for example, on a hot day outside, and you might have some cooling on the inside, you don't want to have a window that's radiating heat. So the thermal heart plus polyamide system and the double glazing or the trip glaze unit prevents that heat transfer from happening. And the inverse of that is on a cold winter's night, where the inside of the house might be nice and warm. We don't want the cold filtering through the glass and the frames to make the inside surface cold to the touch as well. And also the condensation risks around that. We want our bad old windows condensating. So with the thermal heart plus system, with the glass and the polyamide frames, we're way better off. What about for us as a country? What does it mean for New Zealand as these systems improve? So for a country, there's obviously the health benefits. If we're preventing, for example, condensation on the inside of windows, the condensation can cause mold growth, because it's a source of food for the mold. The health benefits of that generally warm my houses, so from a health perspective, it's really good. There's the energy perspective as well. We're quite like, I suppose, we have a lot of green energy, but we have a shortage every now and then. So by controlling that thermal transfer of heat or cold through the thermal heart plus window system, we're going a long way towards, you know, conserving energy. Because that's what drove the H1 changes in the first place, wasn't it? Yeah, it was a desire to work towards reducing our carbon emissions. Yeah, for sure. New Zealand houses are well built by their stick frames, and what I mean by that is the forward to framing, and they kind of always have been so. We've got a pretty tough gig to create a great thermal break through walls that are reasonably thin. So yeah, so the increase in energy codes was to make houses better with what we've got and the windows that fit within them. Literally, to use less energy, to consume less energy in less carbon, and just make them better. So with the fact that New Zealand houses are stick built in, that that's obviously, you know, distinct to New Zealand, how do you design your products, knowing that that's the vast majority of how they're going to be used? Yeah, so we've got quite a bit of work to do, because we don't have much wall space to achieve it, you know, because our stick framing is traditionally four bitoos, right, which is not not a lot of room, and within those four bitoos is installation elements. So we've got that same amount of thickness to make our windows and doors work. So for us, it's crucial we have a systemised approach, you know, with glass, you know, the window frames and the installation method to try and maximise that thermal technology across that very narrow band of what we've got to work in. Because, you know, in say other countries, you know, it's probably maybe it's masonry, it's 140 mils thick. It's almost, it's like almost double what we're working with. Yep, yep. Yes, so we've got a bit of a job to do to keep our windows nice and compact and yet still perform really well, and we just need that technology to make it happen. Tell me a bit about centrifix too, because that's quite a big change, particularly given how thin those walls are. It is, yeah, yeah. So centrifixes are, is a massive step forward in the way windows are installed, and I fundamentally, the way buildings are built in the way windows are put in us, still the same as they were a hundred years ago, which is they sit slightly outside, slightly in line of the insulation. Yep. And we don't control the airspaces while between the windows and the walls. So centrifix seeks to change that, and obviously with, you know, with a code like H1 ramping up requirements, we could no longer, so well, the glass is excellent. The window frames are excellent. The walls are great because they're full with insulation, but we can't ignore the gap around them. And so centrifix really addresses that. So I spoke before about the control pockets of air, you know, the double glazing, the family improved window frames with the polyamide strips, the insulation on the walls, but we had this large gap around the windows that was not controlled. So centrifix controls at airspace perfectly, no different to what's happening in the frame in the double glazing. So we get a complete thermal line between the glass and the wall, the wall framing. So that was really the last piece of the puzzle in terms of improving that whole, you know, window as part of the thermal envelope to just improve that last piece. What does it actually do? How does it work? Windows and then use it on the window and door market for probably the last 50 years have been put into rough openings, which have clearance around them. And the clearance around them is to fit the window in because our building again is stick framing. It's not that accurate. It's, you know, it's better this time goes on, but we need tolerance gaps to fit windows in or they just don't fit. We don't generally come and plaster up, like they might in Europe plaster up and so on outside the fuller gap. So we have this tolerance gap all around the windows, which we need to get them in. And then so centrifix controls the front of that tolerance gap and it pretty much rules a line between external environment and internal environment. And does it actually the same as what the glass does, it controls the spaces. And so the the air temperature outside of the controlling space divider can be cold, but inside of that it's an insulated element. So it's no different to a piece of double glazing or a thermally broken, a thermally improved frame. It's no different to that. I mean, I think Dave, a lot of what we're talking about here is new builds, but what about renovations? Because that's a massive issue to sort out is to kind of upgrade the existing housing stock, which in some cases is pretty poorly performing. Yeah, so with the experience of the team, you know, long-term players with good practical experience, we know how houses are built, we know why they were built, we know the type of windows they had. And we also know how to apply new window technology to those houses to provide a better outcome for the client. I hadn't really thought of us as building in a particularly unique way. I mean, how, how do you design around that? You just got to have your ear to the ground. We've got a great relationship with our builder and architectural clients. And because New Zealand's a small market, we see a lot of variation on the way houses are designed. We've also got the standards to frame building types, but the architectural houses can be quite different. So we've got really good knowledge of our, what our architectural community wants in terms of windows and doors. And most importantly, how we should apply those windows and doors to their style of architecture. Where do you think see things going from here? You talked before about triple glazing, about, you know, the capacity to change. What's coming down the pipe? What are you excited about? Yeah, so I think the whole centrifix idea is just that it's beginning. There's so much more we can do around that in terms of, you know, controlling those air spaces even better, more efficient ways of building and putting windows in. In terms of, you know, the thermal performance of the frames and glass, we've got enormous scope to improve those with the systems we have with subtle changes. So for example, triple glazing, we can, you know, we can reasonably easy for triple glazing and we can fit in larger polyamide strips to cope with any changes of code. So we've got this whole kit bag of of opportunity to, you know, keep on improving our products if we choose to or when we need to. So yeah, we've set in place with thermal heart plus the platform for many, many years of improvement and we're only just beginning with that. That was Dave Bergrav, Senior Design Engineer at APL, talking to us as part of the New Zealand made podcast series. Thanks, Dave. Yeah, thank you.