April 29, 2025
199 - Commercial Timber Guidebook with Danny Hopkin and Luis Gonzalez Avila
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We know a whole lot more about mass timber in fire than we did a few years ago (even when I’ve just started the podcast 199 episodes back …). But is this knowledge widely used in engineering practice? Is it used in the same way by different stakeholders? Definitely not.
This is why to move timber into something we would consider “new normal”, we need more than research. We need a consensus on how to apply the outcomes of our research in practice. And this is this podcast episode.
Built by Nature, with a group of investors, property owners, and managers, funded a grant led by Elliot Wood to write a “consensus” guideline on using mass timber in office buildings. A large part of the book covers fire, which we also cover in this podcast episode.
I’ve invited prof Danny Hopkin and Luis Gonzalez Avila from OFR to walk me through the story of the guidebook, its contents of it and we also jump deep into the design philosophy of the book.
https://builtbn.org/knowledge/resources/commercial-timber-guidebook/
In this podcast episode, we try to stay away from explaining how timber burns (sorry!). But if you want to know more about physics, the Fire Science Show has you covered. Check out the timber section of the podcast! Look here: https://www.firescienceshow.com/categories/timber/
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The Fire Science Show is produced by the Fire Science Media in collaboration with OFR Consultants. Thank you to the podcast sponsor for their continuous support towards our mission.
00:00 - Introducing Mass Timber's Evolution
03:36 - The Commercial Timber Guidebook Origins
08:18 - Addressing Industry Pain Points
13:15 - Office Buildings and Height Categories
21:55 - Compliance Pathways for Timber Buildings
33:23 - Fire Safety Principles Framework
42:51 - Case Studies Demonstrating Principles
58:02 - Designing with Confidence and Consensus
WEBVTT
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Hello everybody, welcome to the Fire Science Show.
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I really love to observe how the knowledge base or the experience base of our fire safety community grows over the time and in some cases you can really observe how we know more with every passing year, with every published research project, with every published book.
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We feel more confident in what we're doing, and one part in which it's very easy to observe this progress for me is mass timber, and this is also something that gives me a lot of joy because, as I reflect on the Fire Science Show, mass timber has been brought in here numerous times and you can even, to some extent, see that evolution as we discussed it with my guests, jumping from some general concepts and problems with mass timber that were quite obvious even years ago up to very sophisticated knowledges and solutions that are presented more recently, and today's episode is no other than that.
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I have mass timber for you again, and this time in a very useful and actionable form.
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This time we're not talking about fundamental properties, we're not talking about how timber chars, we're not really talking about the results of scientific research, but we're talking about industry consensus on how to build with mass timber, how to build office buildings in mass timber or in hybrid structures.
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For this podcast episode I've invited two guests, my colleagues from OFR, dr Danny Hopkins, who you know very well from the podcast, and he's also joined by Luis Gonzalez Avila, and together we are discussing a published piece called the Commercial Timber Guidebook, and on the cover it also has a subtitle Industry Consensus Guidance for Good Practice Mass Timber Office Buildings.
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And it's exactly that it's.
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It's something you can consider consensus.
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You'll learn in the podcast what does that mean in case of this episode and it also covers a lot of good practice on how to use mass timber office buildings.
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So, going from all the research, all the knowledge base that we've already covered in the podcast so many times and I put some links to the episodes in the show notes so you can perhaps reflect on the journey and on the basis for this After really actionable good practice guidance that moves us closer to designing and building with Mustimber the book itself is open access, so I'll leave you a way to access this publication in the show notes and for now, let's spin the intro and jump into the episode.
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Welcome to the Firesize Show.
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My name is Wojciech Wigrzyński and I will be your host.
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If you're keen to find out more or join OFR Consultants during this exciting period of growth, visit their website at ofrconsultantscom.
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And now back to the episode.
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Hello everybody, I'm here today with Danny Hopkins from OFR.
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Hey, danny, hi Bocek and Luis Gonzalez-Avila.
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Hey, luis, nice to meet you.
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Hi Bocek, nice to meet you.
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Thanks for having me and Danny's in the podcast.
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So we're going to talk about timber.
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What a very new, fresh topic you brought to the show, danny.
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I appreciate that.
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Well, it's a fan favorite.
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Becoming a bit of a one-trick pony, I fear.
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It's a good trick.
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Anyway, the reason we talk is a very interesting publication that was published last year, if I believe.
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It's called the Commercial Timber Guidebook and it has a side title Industry Consensus Guidance for Good Practice Mass Timber Office Buildings, and it's a piece that's moving us forward in the discussion about safe use of timber from, let's say, academic considerations to real, actionable guidance that people can actually work in design with.
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Perhaps it's not the first piece that does that, there were many others, but I find this very interesting and complete.
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So, first things first.
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How did it come up to life?
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Who was doing that Because I see it's a large consortium and how did it start?
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Yes, you're right.
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Wojciech, I think one of the key things about the guidebook is the huge element of collaboration.
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So it originated from a grant awarded by Build by Nature in 2023 to the consortium that we were part of in ORFAR and that was together with our partners, structural engineers, elliot Wood, wode Düsseldorf, architects and insurance specialist, lignum Risk Partners.
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This was with the aim of developing guidance that addressed durability and moisture and fire safety in office buildings of mass timber constructions.
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Essentially, it was developed with the intent of it being a reference tool, as you were saying, of good practice guidance for designers, but with an element in mind of providing reassurance to insurers that their key concerns are adequately considered.
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So the genesis of the guide was in the grant that was provided by Built by Nature, but recognizing the benefits of some kind of consensus around durability and fire safety.
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We then got an awful lot of support from the developers people actually ultimately procuring mass timber buildings so there was a very generous group of collaborators who have an interest in developing timber buildings.
00:06:05.492 --> 00:06:11.891
So there was a very generous group of collaborators who have an interest in developing timber buildings that put additional funding into this to to allow it to happen.
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Yes, definitely so.
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It's both developers and asset owners that made up that group, some of the largest in the uk, and it consists of berkeley estate asset management, british land derwent, london, hinds.
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Berkeley Estate Asset Management, british Land Derwent, london, heinz, landsec, lendlease, muse Related, argent and Stanhope.
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So yeah, as you can see, there was lots of collaboration, starting from the funding through to the development of the book, with our partners.
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There was also numerous contributions from the insurance sector and other consultants and academics in the fire engineering world and networks, including td uk, timber development uk.
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So you'll see there's a list of acknowledgments within the guidebook itself.
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It is very impressively long.
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A question then follows.
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So if the building owners or managers poured out the money, they must have considered this as an important subject that I find.
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People randomly give me a lot of money for research, for random purposes.
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They usually have some points to be solved.
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Did they come with some clear pain points related to mass timber office buildings when this work was starting?
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Or it was just blank page?
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Hey guys, fire is a concern, go solve it it comes from their collective intent to really get the ball rolling in in the.
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You know construction with mass timber.
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Obviously they all have their sustainability objectives and it's a nice material to work with from an architectural perspective.
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It has its benefits structural wise.
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So they do have that in common.
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But, yes, so the reason why they're all involved is because that objective was in finding a barrier with particular insurance, but also there are barriers in in terms of approvals and it comes to those two main risks that the guidebook covers Especially.
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You mentioned Fire Voychek obviously this being a fire science show podcast.
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For fire there was particularly a huge inconsistency in the approach how people address these buildings and what was considered safe.
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So that was not helping the case in the eyes of the insurers, and this is something that was a key for the developers and funders and for us to be able to contribute to through the production of this guidebook.
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And also, I assume, due to the nature of timber, it being a novel, to some extent innovative, material.
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So you're really in the performance-based engineering regime.
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I'm not sure if you call it like that in the UK, but it's something the fire engineers have to craft and if there's no good reference guidance, then everyone does what they think is appropriate, which we all know that in many cases was not.
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You've mentioned durability, so let's maybe give because I know it's not the part that OFR was largely involved in but let's maybe briefly talk about why durability was involved.
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What's in that part of guidebook and then we'll move to to fire, yeah absolutely.
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Um.
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So if we go one page back before the durability part of the book, obviously because this a lot of it comes from the insurance blockers or challenges we and because we have one of our partners who are lignum and they are very well connected and, you know, knowledgeable about all things insurance we do have in the guidebook section that covers insurance provides background and context in particular to to these types of buildings that we're covering in the guidebook.
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But, yeah, following that section, it provides also background on office buildings of mass timber.
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That covers general design aspects, structural system types and engineered timber types.
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And then that's when we dive into the two main topics.
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So, as you were mentioning, wojciech did, first covers moisture and durability Things that are covered in.
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There are challenges around moisture and risk prevention strategies, mitigation strategies, and we both so the team drafting the durability section and us we're focusing on the fire section we both try to follow a similar sort of approach in that we provided background and specific sort of knowledge on the specific topic and it then concluded with a proposed set of principles, if you like.
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Well, that's what they're called actually.
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So there are 10 principles on durability that are proposed by the book as a list of rules, if you like, that you can follow in order to demonstrate that you're addressing adequately that particular risk in the case of durability and moisture.
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I think it's important to understand the requirements coming from different, you know, design objectives people have.
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The main objective of building is not to not burn down.
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I mean that's necessary for the building, but we're not building buildings to just survive fires.
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They have tons of other different functions and understanding those is critical.
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Okay, let's perhaps move to the fire engineering part.
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So how does one approach such a vast subject as mass timber office buildings?
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Perhaps perhaps let's step down a little bit.
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Why office buildings?
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Why this particular type of building that is considered by the book?
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we sort of touched on this in in a few podcasts that I've done.
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So there's the regulatory framework that we have in england, particularly now so, post-gromfell, we've sort of discussed the idea that cladding fires have created concerns around our ability to work safely and responsibly with combustible materials more generally and and therefore the idea of building sort of residential and apartment buildings out of timber has there's definitely been a dip in interest and a dip in confidence in using combustible materials in that context.
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So that has led to somewhat a bias in the market for mass timber building, sort of moving towards the more commercial type buildings, so the, the offices, the retail sort of applications, education and leisure, that kind of stuff.
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Um, there's also the fact that we should, we should mention the built by nature separately funded, uh, the new model building, which is um a sort of guide, how to equivalent to our document which sets out some rules of engagement for how you would construct sort of low to medium rise residential buildings out of mass timber.
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So that was subject to a separate grant that I.
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I recall ucl and bureau haphold were were heavily involved with alongside war fessleton, who sort of spanned out of mass timber.
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So that was subject to a separate grant that I recall UCL and Dura Happold were heavily involved with, alongside Warfesselton, who sort of spanned both projects.
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So two elements.
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One, a guide to some extent already exists to address a particular subset of residential buildings.
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Two is that market forces are kind of driving more commercial timber construction than they are residential.
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So the majority of projects that we're working on are commercial projects, and I think it holds true for most other fire safety engineering consultancies, and not only that.
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It's probably where we're most ambitious, dare I say.
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So it's where the buildings are getting taller.
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We're using a higher proportion of wooden elements compared to elsewhere.
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So with that comes potentially higher consequences of fire that need to be addressed.
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And I suppose the other thing worth noting is that timber has all its great sort of sustainability and embodied carbon benefits.
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But what it also lends itself to is building quite cleanly, quickly and efficiently in urban areas.
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So when we're building in city centres and such like, and when we're constrained by site sizes, the number of deliveries that we can have to site, the need to build things quite quickly in those city centres where you have predominantly commercial buildings, it has a use in that respect.
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So there's lots of reasons as to why we're using timber in that kind of context, and with that demand comes a need for guidance and some level of consistency across the buildings that we're delivering.
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Thanks for bringing back the topic of the residential timber model building code.
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Mike Woodrow from UCL, who is involved in that is a long list of podcast episodes to be recorded.
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I hope I'll eventually be able to get one done.
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But we'll definitely come back to that model code and residential buildings and I echo your opinions on the benefits of timber as construction material outside of your structural properties or aesthetics or other things.
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Why we put it in buildings is just very efficient to build and I I agree with that.
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I've built numerous clt mock-ups for you even, and I also appreciate how clean and and efficient it is.
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Even when one has to trim the slab by 10 centimeters because it's not fitting the steel wave that you build.
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It's much easier to trim a 10 centimeters out of a timber slab compared to trimming it down from a concrete slab.
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So, yeah, I echo that.
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Another thing, that there's some distinguishing in the guidebook about the types of buildings, so perhaps we could address that.
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I wonder to what extent it's related to UK, to what extent it's just general ideas.
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But you put those buildings in different brackets in terms of their height and in terms whether they are mass timber fully or a hybrid structure.
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So perhaps let's discuss those brackets like where they came from.
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Sure, there's sort of two, well, three parameters to think about in sort of clustering or grouping mass timber buildings, mass timber buildings.
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And one is that there's various like I'd refer to them as trigger heights that exist historically in in our fire safety guidance and consequently affect how buildings are designed and operated.
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So there's certain thresholds at which certain fire safety provisions kick in, like we change typically the way we we approach fire and rescue service access.
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Around 18 meters in a commercial building, we have triggers for sprinklers and such like.
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30 meters in commercial buildings we have new bandings in terms of what it means for external walls and such like 11 and 18 now with these features that come into a building and what it might mean for when you move away from something that is wholly combustible towards seeking to contain things like fire and rescue service provisions inside concrete cores and stuff like that.
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So there's some practical considerations there in terms of lining up with when these fire safety measures come in.
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The other thing is, um, we we've spoken a bit about the structural timber association volume safety measures come in.
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The other thing is, um, we we've spoken a bit about the, the structural timber association volume six guide in in the past.
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So one of the first projects that ofr worked on, in the space and in terms of research at least, was developing this guidance document around under what circumstances a structure should be expected to withstand the full duration of a fire, versus it might potentially have a finite life and at some point potentially collapse in the absence of some kind of third-party intervention.
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And that distinction in structural fire performance objectives was made on the basis of consequence classes, and so consequence classes are something that span all of Europe through the Eurocodes and are present in our approved document A, and they're basically a way of expressing how the consequences of failure of a structure relate to the structural robustness considerations that you should incorporate into your design, in particular when addressing disproportionate collapse, and so that introduces another set of triggers in terms of when your structural objective changes, and so if you're looking to survive burnout, certain types of structural form lend themselves more readily to achieving that outcome than others, and and that might be because we're having to constrain the amount of combustible surface area in the enclosure and therefore we might not want glulam beams with glulam columns, with clt slabs, with exposed walls, and that's kind of a situation where maybe we're in the finite survivability, and there are situations where we want to be more confident, as the consequences are fairly ratcheted up, and that might mean a more hybrid form of a structure where actually our vertical elements are non-combustible.
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They might be steel, they might be concrete.
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Our cores, where our fire service activities are contained might be non-combustible.
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But by that finite survivability you mean something we ordinarily would call a burnout like can it survive?
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no, no, finite.
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Finite, as in there is a limited time at which stability is assured.
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Okay, not infinite.
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So it's the distinction I draw.
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So in in the sta sort language, we distinguish it as surviving for a reasonable period versus an adequate likelihood of surviving burnout in terms of those two different objectives.
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And so yeah.
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So if you're in a situation where, for whatever reason, you're accepting that your structure doesn't need to survive the full duration of a fire without third party intervention, then that gives you a bit more freedom in terms of the amount of combustible structure you might be willing to include, and that is generally appearing in the guide as things that are less tall and therefore have lower failure consequences.
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So those three things ultimately lead us to group the buildings into different height brackets, and then also noting that when we talk about mass timber buildings, a mass timber building can take many forms, so we can have a pure timber building, and by that I mean we're building all of our structure out of timber.
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So that's glulam frame, cross laminated timber floors, potentially even your cores, formed as, as cross laminated timber.
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That works to a point from a structural engineering perspective, because glulam isn't as strong as steel, for example, so your vertical elements can get quite big.
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That means as you go taller, you might consider some amount of hybridization, where you take the benefits of using steel for your vertical elements and potentially your beams.
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Yeah, so a mass timber building can have elements of mass timber and elements of other materials, and I think we are increasingly making use of the benefits of other materials as the height and the size of the building increases.
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In this hybrid, let's say bracket?
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Do you also consider buildings Like?
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You buy a building in a Primal location in London, you clean it inside, you add five floors from CLT.
00:20:22.969 --> 00:20:29.309
Is that again in your nomenclature a hybrid building or it's something else that's not included?
00:20:30.152 --> 00:20:37.962
um, you know, in totality it's a hybrid building, I suppose, in that you have this sort of melange of materials that you you wouldn't have otherwise had.
00:20:37.962 --> 00:20:52.561
I think it's important to stress that, for the purposes of the guide, we we specifically excluded that kind of nuance where we're dealing with refurbishments and extensions, because it is in itself a very case-specific, complex thing to resolve.
00:20:52.923 --> 00:21:01.769
So we sort of positioned the guide somewhat conveniently to address sort of wholly new structures that are of of that form.
00:21:01.769 --> 00:21:08.603
So in that sense when we talk about hybrids we're really meaning the new building is using a selection of materials in concert.
00:21:09.005 --> 00:21:09.467
Yeah, cool.
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Okay, let's talk compliance pathways, because you even have an entire sub-chapter in the guidebook saying about inadequacy of approved document B, and it mentions the cross-report.
00:21:20.561 --> 00:21:25.069
I think we've talked about that in extents in previous podcast episodes, danny.
00:21:25.069 --> 00:21:40.481
Let's talk about what compliance pathways you actually have, and by compliance pathways we obviously refer to the British system, but some of these considerations may be also applicable elsewhere in the world, so I hope it's interesting to the global audience of the Fireside Show.
00:21:40.481 --> 00:21:49.442
So how does one get timber building compliant, danny Housley, and in what part of that process this guidebook becomes relevant to that process?
00:21:49.950 --> 00:21:54.923
So I guess my first point would be that we don't have a UK regulatory framework.
00:21:54.923 --> 00:22:02.261
We have all of our devolved nations, so we have separate regulations in England, wales, scotland, northern Ireland.
00:22:02.261 --> 00:22:09.223
Now there is some commonality in the language they use and how they structure those, but there are also differences.
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So I'll kind of express this from an englishman's point of view.
00:22:16.796 --> 00:22:38.739
And that is, if we, if we park the, the building safety act and all the high risk building discussion, as has been covered in a in a podcast by my colleagues in the commercial building worlds, you have the building regulations, where you have regulations b1 to b5 that address effectively escape and warning internal fire spread via the linings internal fast, but via the structure, external fast spread and then fire and rescue service activities.
00:22:38.739 --> 00:22:49.262
And each one of those regulations and their subparts are what I would call functional or performance based, in that they they are telling you what to achieve.
00:22:49.885 --> 00:22:56.276
So I always use the structure one, because it's the one that sticks in my head, is that the structure should remain stable for a reasonable period in the event of fire.
00:22:56.276 --> 00:23:10.577
That is the legal test of compliance, if you like, um, and there's similar, similar sentiments expressed like which thou shalt adequately inhibit fire spread over the external surfaces and from one building to another, or something of that sentiment.
00:23:10.577 --> 00:23:12.441
And so you have that.
00:23:12.441 --> 00:23:25.680
That is the law, if you like, but the law within it has some vagueness, you might say, or it would require a case by case consideration as to whether you have done something adequately or reasonably.
00:23:25.680 --> 00:23:33.859
So appealing to those performance based requirements on a case-by-case basis, using first principles, would be really really quite challenging.
00:23:33.859 --> 00:23:39.369
It would require a huge amount of competency on everybody in the design team, on every single building that you're working on.
00:23:39.369 --> 00:23:51.182
And so, in parallel with with this change which happened in 1985, which is a stellar year, as you'll appreciate, before we check, absolutely and's the production of approved documents.
00:23:51.769 --> 00:24:18.137
And so the approved documents are a set of recommendations that if you follow them in their entirety and apply them to common building situations, which is not specifically defined by the approved documents, then you can be considered in all likelihood to comply with the building regulations and the building act as the primary legislation would actually say that you would, as a designer, tend towards negative liability if you, if you, did that.
00:24:18.137 --> 00:24:24.596
So the approved documents give you a set of tools to support compliance for common building situations.
00:24:24.596 --> 00:24:44.483
Within there is is a series of heuristic shortcuts, rules of thumb that implicitly assume certain features of your building, because these rules or bits of guidance originate from things like the post-war building studies and from a period where construction wasn't especially innovative, to be honest.
00:24:44.483 --> 00:25:05.933
This and so using and relying on that guidance to demonstrate compliance for a mass timber building potentially has a whole host of pitfalls, because you're taking a material which is combustible and applying it within a guidance-based framework that develops a lot of its rules of thumb from experiences of non-combustible construction.
00:25:06.173 --> 00:25:15.907
And so if you're trying to get a mass timber building ultimately approved so it can be constructed and you can evidence that it complies with the building regulations.
00:25:15.907 --> 00:25:36.832
You almost have to work through every single one of these requirements and consider the impact of your structure being combustible on the ability to adequately inhibit, support means of escape, whatever it might be, and whether you can sensibly rely on those, those rules of thumb in the guidance, or if they're insufficient because they have certain limitations.
00:25:36.832 --> 00:25:44.400
And so the I think a mass timber building affects almost every element of the fire strategy and therefore compliance.
00:25:44.400 --> 00:25:59.066
But if we're going to focus on a few of the ones that get discussed semi-regularly, one is the idea of using fire resistance periods as a proxy for surviving the full duration of a fire, which historically have assumed that your structure is not contributing as a source of fuel.
00:25:59.790 --> 00:26:04.750
Arguably, they were invented to move from timber to non-combustible structures.
00:26:04.990 --> 00:26:14.066
Indeed, they were in fact a response to timber structures and the need to start evidencing the fireproof claims of products in the 1800s 1900s.
00:26:14.066 --> 00:26:21.699
So at that point, when your structure is involved as a source of fuel, you're going to need to find a way to evidence that it is going to have a reasonable likelihood of surviving the fraudulation of the fire.
00:26:21.699 --> 00:26:35.296
And that's where your role as an engineer is moving away from the application of I don't use the word prescriptions, because then they're not really but instead of relying on recommendations, you're doing something a bit more involved, a bit more first principles.
00:26:35.296 --> 00:26:39.455
It might be a fully performance-based assessment, using models or whatever.
00:26:39.455 --> 00:26:41.417
It might be a semi-qualitative judgment.
00:26:41.417 --> 00:26:44.257
There's lots of different ways to achieve the same outcome in my mind.
00:26:44.730 --> 00:27:14.861
But in recognizing that there's these bunch of hazards that are not addressed by the guidance, we've got a manual for how to do calculations and evidence the performance of a mass timber building.
00:27:14.902 --> 00:27:25.442
We're still we're still learning about the features of mass timber buildings and what does present a particular challenge and what doesn't, and so there is a real variety in how people are approaching that.
00:27:25.442 --> 00:27:29.756
It's a real variation in in the amount of diligence that's supplied.
00:27:29.756 --> 00:27:33.761
There's a variation in the amount of conservatism that's applied.
00:27:33.761 --> 00:27:36.191
Some of us are a bit more.
00:27:36.191 --> 00:27:42.071
I'm more of the mind that if there's an uncertainty in design and you can easily remove it, then you should.
00:27:42.071 --> 00:27:48.836
Others are a bit more liberal in how they might sort of take on that uncertainty and then accept it in their design.
00:27:48.836 --> 00:27:50.892
That kind of speaks to them.
00:27:50.892 --> 00:28:20.856
So I was just gonna say that kind of speaks to the motivations of this guide in many respects, because that variation in responses in evidencing the adequacy of a design um creates some nervousness in amongst the insurers and also the approvers, because different people are coming to them with broadly the same sort of designs but presenting the evidence to them in different ways and to different, varying extents of diligence.
00:28:21.037 --> 00:28:28.055
In my view, one can present an analysis, even based on first principles, but just bad assumptions.
00:28:28.055 --> 00:28:34.492
That a building can be safe with some questionable safety guidance in it, it's possible.
00:28:34.492 --> 00:28:35.876
It's just how you craft your design.
00:28:35.876 --> 00:28:49.402
Fire, for example, another person can just mindlessly stack safety margins on top of each other and end up in a structure that's extremely expensive and perhaps inhibits the intended use of that structure.
00:28:49.402 --> 00:29:02.296
So there is a sweet spot, or there is a good spot to be, and I assume that the principles defined in this manual actually guide people to finding that sweet spot in a more reasonable manner.
00:29:02.296 --> 00:29:08.961
There's also something called qualitative design review, qdr, mentioned in the guidebook.
00:29:08.961 --> 00:29:12.094
So if you could perhaps elaborate on that, yes, absolutely.
00:29:12.275 --> 00:29:12.615
Porcek.
00:29:12.615 --> 00:29:29.799
So I just also wanted to highlight that all of what we're discussing at the minute is almost like a first part of two main parts that form the FHIR section of the guidebook, this part being authored primarily by us in OFR.
00:29:29.799 --> 00:29:31.262
It's almost setting the scene.
00:29:31.262 --> 00:29:42.859
So, yeah, we've covered what you guys have just discussed in terms of routes to compliance and in that aspect, the QDR is the process.
00:29:42.859 --> 00:29:53.200
So yeah, as you mentioned, qualitative design review process that is standardized in terms of a set of steps that comes from British Standard PS 7974.
00:29:53.200 --> 00:30:27.118
And it's essentially a framework to undertake a fire engineering assessment, from the initial steps of analyzing the architectural design, the architectural proposal, and going through each of the objectives of the stakeholders, clients and the approvers and all the designers, Obviously, for us a key one being life safety, which is a primary objective of any fire safety design, but the specific building can have other objectives.
00:30:27.570 --> 00:30:28.916
We've been talking about insurance here.
00:30:29.130 --> 00:30:38.049
So there is a lot of discussion within these first parts of the fire section of the guidebook about property protection, business continuity.
00:30:38.049 --> 00:30:46.955
So it's identifying those goals and then establishing the possible fire safety solutions in order to address those goals.
00:30:46.955 --> 00:30:57.943
Fire safety solutions in order to address those goals that goes with setting the acceptance criteria and how the methods of analysis are undertaken in order to achieve those goals.
00:30:57.943 --> 00:31:10.476
All of that is something that in an ideal world I say, but actually we believe that's the way it should be done and that's the way we try to do in our projects, believe that's the way it should be done and that's the way we try to do in our projects.
00:31:10.476 --> 00:31:15.006
That should be part of a conversation with the approvers and all of the key stakeholders.
00:31:15.006 --> 00:31:34.461
So insurers should be part of the conversation and that's how you so, from the beginning of your project, establish what you're planning to do essentially so how you're going to be demonstrating the life safety or what the other objectives are met and how you can go about showing that to approving authorities.
00:31:34.809 --> 00:31:41.820
I also appreciate that you put structure in this, so it's not just general consideration that what should be done.
00:31:41.820 --> 00:31:56.712
You propose a list of principles that you, I assume, test against for, or that you should meet in your building, and then you give some considerations on what's the fire engineering approach that's going to meet that principle.
00:31:56.712 --> 00:32:01.592
I'll take the liberty to quickly list the principles, because it's it's a list of 10 of them.
00:32:01.592 --> 00:32:05.382
Well, there's sub points, but in general there's 10 of them and they start with zero.
00:32:05.382 --> 00:32:06.673
There's much more than 10.
00:32:06.673 --> 00:32:10.681
Come on, guys, it's not 10.
00:32:10.681 --> 00:32:11.963
I'll go through that.
00:32:12.349 --> 00:32:15.039
Zero fundamental principle, comprehensive fire strategy.
00:32:15.039 --> 00:32:16.615
That's the first one.
00:32:16.615 --> 00:32:21.082
Then it's followed by adequate risk to health and safety and adequate risk to health and safety B.
00:32:21.082 --> 00:32:23.730
Well, adequate risk to health and safety, okay.
00:32:23.730 --> 00:32:36.445
Then there's assumed redundancies for life, safety design, impact on escape from area of fire origin, mitigating internal and external fire spread, and that subdivides it into vertical and horizontal fire spreads.
00:32:36.445 --> 00:32:50.049
There's expected performance of structure and compartmentation, survival of burnout with encapsulated mass timber, survival of burnout with exposed mass timber, sensitivity, consequence, consequence analysis and smoldering combustion.
00:32:50.049 --> 00:32:51.455
So that's the list.
00:32:51.455 --> 00:33:04.721
I assume that this is the list of principles that the fire engineer should consider when designing them buildings, and then address them one by one, in what way they their engineering design refers to them, meets them.
00:33:04.721 --> 00:33:07.509
What's the intent between for this structure?
00:33:07.991 --> 00:33:12.397
so, going back first to what I was mentioning, that makes up the fire section.
00:33:12.397 --> 00:33:13.623
This is that second part.
00:33:13.623 --> 00:33:16.071
So first part, we have already set the scene.
00:33:16.071 --> 00:33:18.798
There's also a lot of good content in there.
00:33:18.798 --> 00:33:24.836
This talking about the way timber burns and the hazards this presents to buildings.
00:33:25.358 --> 00:33:37.093
I have to apologize you for not going in that, because you probably wanted to talk about that, but the listeners of Fire Science Show are very well aware of that after numerous episodes with Dr Hopkins.
00:33:37.093 --> 00:33:39.662
Absolutely yes, yes no problem.
00:33:39.682 --> 00:33:50.991
I decided to jump straight to the principle, but I also want to actually I want to emphasize the language that's used in the guidebook, the aesthetics of the guidebook, the way it's presented.
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