Mass Timber and the Scandanavian Effect

hello my name is michael voloney i work at the development and alumni relations office at the graduate school of design i'm delighted you're all here and i'm very excited to be able to introduce jennifer bonner and hanif kara for this mini course on mass timber and the scandinavian effect jennifer bonner is an mark 09 an associate professor of architecture at the gsd and director of maul founded in 2009 born in alabama bonner is a recipient of the architectural league prize for young architects and designers emerging voices award progressive architecture award and next progressives she is author of the guide to the dirty south atlanta and guest editor of art papers bonner received her bachelor of architecture degree from auburn university and her master's from the gsd of course where she was awarded the james templeton kelly prize for her project assemblage of twins bonner's previous work includes time at woodbury university in los angeles georgia institute of technology auburn university the architectural association and lund university she's also held positions at foster and partners and at david chipperfield architects uh hanif kara is professor uh practicing structural engineer and professor in practice of architectural technology at the gsd he is recognized for linking design research education and practice he previously taught at the architecture association london and kth stockholm as design architect and co-founder of act 3 his particular design led approach and interest in innovation form creatively manipulating material uses and the complex analysis methods have allowed him to work on many pioneering projects at the forefront of challenges facing the built environment hanif's career extends into wider areas of design beyond the structural engineering disciplines this led to him receiving the uk ace engineering ambassador award in 2011 he's the first engineer to be appointed on the steering committee for the highly uh regarding international augacon award for architecture hanif has also contributed to a number of published works including most recently editing design engineering refocused and the architecture of waste they will present on their spring 2020 option studio mass timber and the scandinavian effect hi my name is jennifer bonner and i'm an associate professor of architecture and founder of a firm called mall and i'd like to introduce my colleague hanif cara who is a professor of practice in architectural technology and founder of akt2 a structural engineering firm in london so today in the next 25 minutes we're going to talk about the pedagogy of a studio we co-taught together in spring of 2020 titled mass timber and the scandinavian effect we're going to talk about the impact of covid19 on our teaching we're going to show you four student projects in detail and we're going to close with our thinking about where this work is headed in the field hanif and i discussed we wanted to start with this project which demonstrates our collaboration from over 15 years ago at the time i was a junior architect at david chipperfold's office in london and we were working on this project where hanif was a structural engineer it's called the turner contemporary and it's a gallery in england's eastern seaboard in a small town called margate and if we fast forward to 2017 this is house gables in atlanta georgia and this is the first project that i built with my practice hanif was the structural engineer and this is a house constructed out of 87 cross-eliminated timber panels installed in 14 days time with a four-portion crew so we really thought that this is kind of the starting point of this collaborative teaching model so thank you jennifer for that introduction um i would like to color in with three more slides so some examples of of what's going on in practice in the search for the use of timber particularly in the last five years this first project is uh uh with the thomas hedowick it's the maggie's health cancer care center in leeds up in the north of england it's a sculpted form and we used three to four different types of mass timbers in here so it's a it's a petite jewel-like form but it does have clt glulam lvl and a number of other mass timber products the goal here was to use mass timber as a contribution to health the second project and that i wanted to just use to color in our experience is the high point residential block and it's not the tower it's the line flow high ground scraper that you see adjacent to the tower which is made out of clt in its entirety the walls and the floors and in this particular instant it's not decorated the architects were richard rogers stark harbour partnership and then a third project which is the largest clt floor in europe currently it is at king's cross it's of course the headquarters for google and the clt flaws in this instance sit on steel beams it's on site right now so it's a hybrid and the main purpose of clp here or the main use of clt certainly in the floors was to allow us to be able to make these floors removable during the lifetime of the building to change the configuration of the way we use the inside of the building as it happens the walls or the external facade which is free from the structure is also made of glue lamp the architects here are priyaka ingles group and thomas to move on to the studio i want to say maybe two or three things that are a long-term motivation as jennifer already mentioned we've known each other for quite some time in that time my 10 to 12 years at the gsd one thing that i've always been focused on is the role of the architect or empowering the role of the architect so we have in that goal recognized that and at one level architecture is a discipline of material organization in many different orders we also recognize that many significant shifts in the discourse of architecture are prompted by technological advances and whilst la corbusier characterize the relationship between architect and engineer as a struggle this alliance has produced precious outcomes in the last 50 years and we put aside virtual signaling when we talk about that we also see that when there is a fast-paced introduction of any any kind of technology architects are often left behind as newness is driven by industrialization and a technological determination wood is of course something that is close to the modern human it goes a long way back and there is a lot of discussion wood there's a lot of discussion on mars timber in our case we wanted to use cross laminated timber as the focus and we've set out to search new design ideas and visions and the studio represents only part of that work jennifer will talk about the compass that we are using in the studio in a moment what is though important is to say that we're acutely aware of what's going on out there in the world when mastimba is is raised as a subject what we see in the press and what we see built ranges from hysteria through to some aspects of it or at least reality we're acutely aware of that and you see here in the background lots of buildings that are either under construction or already constructed so we were very keen to to be gentle on this and prescribe a careful breathe to our students and in that brief to make sure that there was a a scale taste test done so in that scale we studied the house and a high rise and our definition of the house rise high rise in this case was based on what's already built about 72 meters high and we challenged them to take it up to at least 120 meters high so one of the triggers for that was really the you know this is not really tall the tallest wood and natural trees in california for example are up to 93 meters tall already so there was some way of really capturing very quickly what's going on so that we could set an ambition we also chose to select the mid city raleigh durham in carolina and we wanted to do that specifically because we saw that there is less noise there in a way in terms of studies that are going on but also it's a it's a city that offered us both a site for housing and a site in the center of the city so 14 plots were given to the students as a prescription in addition to that it was important to us that at least for the high rise which is perceived to be the more difficult form that the students should tackle we should at least allay their concerns and start the ground running so that all of the students are at the same page on day one and that was done through giving them a small primer just giving them a basic idea and we did then have detailed lectures on these ideas and the structural concept of the height the notion that you could actually transfer easier with a lighter timber so you can make transfer structures in your form and within the chassis also they could take a number of shapes as they meet the ground so we gave them a primer that and started to limit or at least inform them quickly into the height and the shapes and the form that they could take in addition to that the other areas that they could get stuck in were also primed so they were given the basics of our core works and the service score and how important it is in in terms of its relationship to the form particularly in the taller building of the two and the second thing was really we gave them root of thumb on the floor thickness and the different systems because one of the things that we wanted to explore is the concept of freedom that could be achieved in the floors using walls rather than the the 20th century idea of a free plan with columns so they would have to have some idea of what is the capacity and meaningful potential of the clt flow and we gave them very simple rules of thumb in order to do that together immediately the last thing that we thought that would stump them would be the stability because that lateral wind loads become quite a big aspect of the architecture in tall buildings so we gave them a range of rules of thumb on what is possible in the kind of heights that they're talking about and also related these back to known door buildings that are up to formed and meter store sometimes where we use either the exoskeletal or the core we also planned and the studio as a multi-year idea at the beginning of 2020 and one of the the things we managed to achieve pre-covet was really to get to martinson's factory up in northern sweden because we wanted the students to see and get a feel for how clp is made its relationship to the forest which they were all able to witness but also look at this 72 meter tall building by white architects in skeleta which is quite a tall building which is currently or was at that point under construction so we want to get them to get a feel for what was possible equally we also wanted to show them some of the great architectures that are available in in sweden because one of the concepts was really can we find a scandinavian effect in the work we do we developed the studio around these four conceptual underpinnings the first questions the emergence of effects in recent architectural history and locates the design projects in the american south the third and fourth themes challenge the aesthetics of wood and what we are calling clt blanks to start if we think about the notion of effects the moment when a strong pattern emerges within the architecture discipline we begin to label it and sometimes figure out its recipe and it is regarded as a shift in paradigm the bilbao and dubai effects come to mind as two effects around the iconicity and gravity-defying skylines a third effect can be dated to the 19th century just after the great fire as the city of chicago's rebuilding effort resulted in the first tall building constructed out of structural steel one-third the weight of its masonry counterpart steel towers were fast to erect and exceeded fire code a new type was born labeled the chicago effect currently we see yet another pattern emerging with the architectural and structural advancement of mass timber specifically in the scandinavian countries where towers housing and cultural centers are being marching forward in engineered wood and unimaginable scales throughout the semester the students have designed two projects tackling the programs of a single family house for 10 people in a mid-rise tower mises house in tower pairing is revelatory but the house and tower share a structural solution in the column detailing and we almost forget that there is such a significant difference in the height between the two we see this translation as part of the pedagogical experiment from house to tower timber a familiar material in type 5 construction within the us translates seamlessly to the single family house from wood framing on the left to cross-eliminated timber panels on the right clt offers an alternative as two by sixes are now laminated together into large panels with an overall reduction of construction time factory precision for geometry and now we have buildings with solid walls constructing mid-rise towers out of wood is counter-intuitive yet parallels the revolutionary thinking of steel construction in the chicago case here is what we are calling the clt blank comprised of three five and seven ply laminated timber panels they measure nine feet in width and fifty foot lengths foregoing the four by eight sheet material of the past with endless possibilities for openings shape and geometry and lastly we've asked the students in the studio to make up a representational position around the aesthetics of wood from ikea's 2015 furniture collection to sam jacob's plank scarf for sale at 30 pounds the image of wood is on trend as contemporary artists grapple with real and fake imagery of wood architects absorb the image of wood into contemporary interiors we've asked the students to define the aesthetic of wood both as a representational device but also as a tectonic question that hopefully becomes central to the positioning of each project this is an image of the students 14 houses and 14 towers and we like these images because they remove the projects from the original context of site located in raleigh durham and show the designs kind of as a collective set one other thing to note is that the representation of the studio the students were very interested in the tectonic of the clt and the mass timber and so several students did construction sequence erection animations they were thinking about the clt blank at the size of the tower they also had programmatic implications and then in the bottom right you can see where a student has really showed you what the milling of the surface of the seals he looks like in a scalloped form so as jennifer said the project of the house was finished almost finished when covid hit us so literally the day when the flights were all stopped faculty were unable to travel we were amongst the last of the students i think still in gun hall and were able to pull off a midterm review on first half of our semester by fluke and this setup of two projects one in either half of the semester is actually now proving to be a model to work with as we go forward and encode it wasn't our intention at the time but fortunately for us both the idea of co-teaching and the idea of splitting the semester into two halves is quite a it's quite a benefit because that's how we believe that the next year and at least this fall semester will be conducted one thing that will be absent is the physical models that we can make we are all close to and used to and have the ritual of having physical models made of our project and and that becomes a drama um that is so so much fun usually in mid reviews but obviously in this instance it was slightly subdued so we changed gear very very quickly within a week we were on zoom as you can see and to begin with it was rapid in terms of adapting the process and adapting the meetings we found ourselves at least seamless in in the way that we conducted meetings and had tutorials and individual meetings with students on a weekly bi-weekly and sometimes more often than that so one thing we saw very quickly was both jennifer and i found that we were having to spend a lot more time with the students trying to not only get to the pedagogical question that we wanted to answer but also just the physical understanding of how one designs when we're not together in the same room but also bringing together the students as often as we could on screen so they could still continue to learn off each other we did find ourselves doing those hours and also at times can the communication system took us back to the analog so rather than being able to draw quickly at discretes and develop schemes very fast we found ourselves doing it the analog way with sketches and scanning and sending these across to students for a discussion which is quite difficult because we are trying to get across a breadth of complex information very quickly so that the students can respond react and take care of it in their project so now i'll start by showing you four projects i'm going to show you two towers and two houses this is a tower by anna goka her project won the james templeton kelly prize um for the grad best graduating project in the mark ii program and she really starts with the clt blank as a simple cut which is like a squiggle and then what she calls is a bandage so a large piece of steel that then bandages two panels together so in her projects there's 300 panels all together and what she says is 400 cuts and 400 bandages so really it's a project that's an exoskeleton and then here you see the facade assembly where she's making her cuts and then reassembling to make that exoskeleton this is a corner view of the project and this is the view on the interior to really show how she set the facade line or the glass line within the interior of the project and so there's kind of two ways of looking at the project there's this exoskeleton and then there's this inside which she's interested in the concept of reassembly so in 24 meter chunks she's proposing that over time you can reassemble the interior based on different programmatic needs this is just depicting the lateral load and the compression and tension where there's a belt placed every 12 meters that works both in compression and tension these are some of the analytics done by akt's office in london this is a belt detail of how that would be actually assembled and then here we see her idea for this flexibility of the interior within the superstructure there is the idea that these nine foot by fifty foot blanks would be reassembled with a gantry system inside of each of the chunks of the tower and so her project was really thinking about the afterlife of the building not just in move-in day and her project proposed a 100 meter long tower the next project is a house by edgar rodriguez edgar also started his project with the scale of the clt blank and edgar was thinking about it as an industrial material one that you could think of it is off the shelf and he was also interested in the idea of a pile of these industrial materials and so quite literally the clt blank has thresholds cut out of it in doorways and then they are assembled together as a simple stacking system [Music] again the idiosyncratic of the plan is basically the length and the dimension of the original clt blank edgar was also interested in the underbelly of the gable roof and potentially a japanese system where you would stain or color the wood of the interior again some of the analytics produced by hani's office and this is the final project view both the interior and the exterior the third project is a tower by benson chen vincent starts out with this notion of a typical 2x4 stud wall in type 5 construction within the u.s and the idea of a cross-laminated timber and so we know in framing walls um out of out of wood framing there you have to make headers and footers and he's suggesting that with the clt panel you have a free form experience and can cut any shape into the panel and he's also thinking about layering multiple panels together and getting different cuts through so this is one of his early studies so this is an image of the clt blank at the scale of the tower and if you'll see this image he's basically taking the blank and then stacking them into the mid-rise tower each of these clt walls subdivides different housing units and he's using a rotation of a grid to kind of change the the angle of each housing unit and here we see a thousand and 37 panels make up the overall form again there's a real tectonic to use the clt blank and it's entirely into kind of notch and stack in a pretty simple manner and here you're seeing the structural strategy which is to start with maybe like a 9-ply clt panel at the base of the tower and as we move up in height the panel is reduced to three ply and so his project kind of has two sides there's the front side which he calls the boolean and the back side is what we could relate back to that balloon frame or wood frame aesthetic and now instead of with two by sixes we're looking at a clt frame and lastly this is a house project by edward han edgar was very interested in the clt as a surface material and what you can do with the actual milling of the surface and so he's proposing staining the surface with colors and patterns and using the cnc machine to cut into the material for the interior his overall concept for the house is to make a house resemble the actual cross laminations of the panel and so here we see his ambitions for kind of scaling up a chunk of the panel and making that the diagram of the house which gives him a kind of dynamic plan view for his house and then here is the kind of stacking of the panels in three dimensions and so what the kind of cnc cutting and staining of the material with various patterns allows for an interior of different rooms and different techniques and i'll hand it back over to hanif so what was next well one thing we had planned um always was that with the notion of a multi-year studio multi a piece of research that a very interesting symposium that brought together people from the industry practitioners academics and others who were pulling together the current narratives on cross-laminated timber to a one-day symposium on gst this was supposed to take place on the april the 10th it was all agreed and most of these speakers were already booked with their flights and the hotels and sadly we weren't able to undertake that the idea there was to go beyond the industrial um or mechanization of of clp and see what are the narratives could be found from these other people who are talking and working in the field and trying to use cld so we had intended to do that and we'll now do that on february 26 next year as you can see some very important people the second out of studio plan was really to make a book a book that would in many ways not be a guidebook or a technical review or a lookbook but an interesting book that would talk about design which was based on blank basically so we have in the last three months continued to make that book at speed and it's progressing extremely fast and the working title is blank which are speculations and cross-laminated timber it introduces the broader concept of blankness and expands architectural theoretical impact this material may have material presence is very difficult when it's not the physical so the book is designed to try and make the material present but equally expand the discourse many themes are already being written up by a select group of pan-disciplinary contributors who are architects artists engineers academics from new thinkers to established thinkers we think it's important that this conversation is held in the open so the narrative can be shared and added to as a dialogue in what is about to happen with this material and the art component is is particularly important to us as well because this material offers certain aspects of of collaboration with art that doesn't separate the artist and the architect unlike what has happened in the market economy where architects have related less to the market economy compared to artists so bringing the artists and architects together to find new aesthetics bringing engineers together to find a new discourse in this area but more than anything else these architects and designers will help us to articulate our discussion the book will also include some of the work of the studio and the projects that we produced and the methods in which we produce the work themes such as flatness aesthetics of clt mechanization from balloons to blank the the compartmented plan is still alive are some of the areas that we have already started to develop writings in and articulate these themes came up during the conversations but also during the planning of the studio and the reviews so we are continuing with our discourse in in this area so more examples of of what has been done by the students already we think it's also important to show the collaboration between academy practice and industry and play that out in the book jennifer mentioned the analysis work that we did in the office to connect things together and what's quite interesting about clt is that because of it's an isotropic as a material and natural the pervasive analytical diagrams and analysis that architects and students are used to and convinced by are not always easy to use to to justify our clt behaves well thank you very much uh jennifer and hanif that was a thrilling kind of exploration in the use of wood we're happy to take any questions about the studio or from hani's perspective what's happening in the field with other architects in europe and abroad very impressed by the ratio of the mass between the timber and the concrete and i'm wonder that sounds like it could be a benefit under seismic loads with the lighter weight and can you possibly talk about whether some of these high-rise these towers have actually considered earthquake loading i think i will take that they haven't because our site was not seismic area but i can say that there is a lot of activity on the west coast and we are a lot of us are doing studies on how to take it across to the west coast where there's high seismic activity and mit i know in particular have been developing joints that can work during an earthquake because the largest issue will be as you rightly point out that lightness is a great benefit but equally the way a panel is connected to each other needs to be carefully designed so it doesn't sheer off there is a lot of work done on the west coast and i i i would be very surprised if in the next two or three years you don't start seeing at least mid-rise towers appearing in the west coast in japan there is now conceived almost 250 meter high tower in a high seismic area so across the world it is going on we didn't put this down we had 14 weeks and we didn't want to frighten the students too much because they are after all their architects we have a question in the chat room um from lily long she's wondering if you could speak to what are the major barriers for mass timber to become more mainstream uh what can the either the public or private sector do to support it and she says i have children running in the background otherwise i would have waved my thanks so no problem sure um i can try to answer lily's questions um so if we think about what's happening in north america or specifically in the us uh there's been a big push towards um getting the icc code 2021 up to speed and so now included in the code which most cities are going to start adopting will be that we're able to build up to 18 stories in mass timber and that's going to be type 4 a construction is what they're calling it with the max height of 270 feet um so those are some of the things that we're seeing happening you know um within code um i think there's you know hanif and i have been talking about some some of things that we didn't include in the studio was like fire rating and those kind of fire testing in those discussions which is definitely um either hinders hinders the building of but i think this new code work is really exciting um and that you'll start to see it in all of your various um cities and jurisdictions yeah i would just add that i think that uh the canadians are taking it up faster than it is in the um and then the europeans are obviously 20 years ahead because austria and scandinavia in particular is almost mandating sweden has mandated that you get a benefit if you are a constructor a tax benefit if you're a constructor and you construct out of wood that's the first case that's happened where there's incentive from government but a lot of going to lilly's question on the private people there is a lot of investment going on all over the world and in the us probably the japanese and the australian developers are ahead of the game because the people like len lees have already got factories that make so the the biggest barrier i suppose will be um the kind of stigma that's attached to wood you know with the historical fires and with the psychology and with it being seen as a non-modern material that can be uh a stigma uh in many parts of the world i think that's going to change and that was partly what we were trying to address the kind of let's call it the beauty of the of the material and not to be afraid of its modernity and it has an offer in that area once you start crossing those thresholds for which i believe you need design not only industrialization or developers investment but you need the kind of thing that jennifer and i are encouraging in the studio we have a another question from mariana athanasiadu she's asking you talked about removing floors during the lifespan of the building how do you resolve the hvac issues in the building yeah so you're specifically talking about anna gogo's tower um i would say uh she was dreaming a little bit with her proposal there um with the conception of you know building in a gantry system every 24 meters within the project that you could have a crane that would be able to move these large clt blanks around um i don't think the hvac and then the florida floor is totally solved i don't know how she was imagining that that would be either added and removed over time or we i don't think she really kind of got that far with her concept um but good question yeah i i mean i can tell you that in practice it's already happening so the building i showed which was google's headquarters one of the things is to divorce the hvac from the floor and put it in a vertical alignment and the other solution is to only put it in every three or four floors so there's a void between the other floors and then attach it to the timber so it's part of the removal process what makes it all possible is the ease with which you can assemble and reassemble and that is going to happen at king's cross in london so we have a question from kiri kara lagayos mass timber has lots of advantages in terms of moving towards net zero carbon goals for buildings did you discuss these factors as part of the course it's definitely a big benefit yeah it's a it's an excellent question and it is definitely the main thing that will break all the barriers and the surge to timber is without any question driven largely by a recognition of the climate crisis because of the the weightlessness but also the carbon footprint in terms of concrete is you know four or five times it's it's cubic meters per square meter is 225 kilograms whereas i think um clt is only about 60 but then you sequester 900 kilograms of it so it's actually a negative number in terms of saving the planet so there's no question that that is the main debate we discussed it but we again because of time and that's why i said it's multi-year we again didn't want to get stuck in the the deterministic attitude that let's call it ecohypness that students could get stuck into so we wanted to say okay we know that problem and scandinavia already understands it there's lots of code and science let's put it aside for this work but certainly we will be dealing with it over time and it is the largest benefit what i would say is the the risk that we have is that if that becomes too dominant again the aesthetics are are put aside and whilst um there should be a priority on climate crisis it shouldn't be at the expense of the other qualities that will make people live here and i think some of our work including jennifer's house were experimenting with that idea of actually wanting to be in these spaces not thinking of them as second-rate or only eco-friendly so that's a good question thank you well there's another question about jennifer's house what were some of the challenges in that project being asked by sophia yeah hi sophia um uh the challenges for me personally is that was my first building project so um it was kind of a steep learning curve but i had hanif kind of supporting and checking in on me every few weeks as i worked with akt to some engineers in the u.s and also the manufacturer which we decided to go with klh in austria and we went with klh and austria not to add more carbon back to the story but because of it really came down to pricing um and so we were able to put 87 panels into three shipping containers and ship them over to the port of savannah and then truck them over to atlanta so i'd say logistics was difficult finding somebody to build it and to work with so actually we i don't know if you notice susan jones is a gsd alumni she we had her set to speak at the symposium that we were going to have she built the first clt house in seattle um washington and and she was you know i was kind of reaching out to her throughout the process um and i've just lost my point of where that was going um this is like saturday afternoon um oh she she had recommended that we um i contacted her supervisor that had put together the her panels in seattle so i contacted him he assembled a three-person crew they flew over to atlanta to put it together so it was difficult in atlanta to find a contractor that had the appetite or wanted to learn about how to put together clt i think they nobody would really take it on so i had to fly people in from seattle to do it so that it was all a big experiment um i'd say the things that we learned positively were that if we're going to try to build small house let's say small footprints and in-town neighborhoods where densities getting tighter and lots and areas to build are getting less and less i would say uh what we learned is that clt you can make volumetric spaces and that's what i tried to do in house gables um even though the the house was quite small it's only 2 200 square feet we have another question from lily huang mass timber and prefabrication often go hand in hand what is the role of the architect as the construction industry shifts off-site what are the opportunities and challenges for design here it's just really exciting um i don't think it's a challenge to work in the digital model in our case we were working in rhino developing a single surface model then we panelized and thickened um all of the panels and rationalized the geometry and basically cut the house up into into the various 87 panels and what's exciting is that model then goes straight to the manufacturer in austria where they start laying out the panels onto their blanks and looking at various tooling paths and how to flip mill each panel to get all the miter joints and connections and and um lap joints that we were able to achieve and the house and all of this is at a precision you know down to like a sixteenth of an inch and so it's like perfectly fits together on site now the only scare there is you can't go and get a clt panel cut really quickly in atlanta if one was missing or if something went wrong but knock on wood that didn't happen um but yeah it i think it's just it's it's super interesting to have that technology in the digital result in that kind of tolerance on site we have another question um concerning the cost relative to more common building solutions so maybe we can you can address that the issue of cost i mean i could try to talk from u.s maybe honey has something to say more from europe um uh you know all i have is my small little example of the experiment in atlanta but um which uh it was it was costly to get it fabricated in austria we saved about eighty thousand dollars then getting it cut at a north american manufacturer we're looking at smart lamb or nordic in canada and so yeah cost is a problem i'm wondering though if you get outside of this single family house and you try to maybe build 10 or you look at multi-family housing can the num will the numbers start to shake out and and i don't know if they'll ever they're never going to meet um you know be better than stick frame construction but i think if the ethos of the country is changing we want to build more solid walls um that you know that are thermally sound and that are more long-lasting than our uh wood framed houses and maybe five or for one you know boxes that we are springing up in cities i think um i think that that's where uh it's gonna have to be an ethos kind of mindset change and shift yeah so i would i would say that in that regard we're slightly ahead or quite a long way ahead uh clt is very competitive for housing and unlike the eight story building i showed you in my in our presentation for example there are several layers of savings so why is the initial concern about it being a specialist material disappears very quickly when you realize that because it's a fifth of the weight you no longer need pile foundations for example so it reduces your foundation system to almost zero and then you have the other benefit that it forces all the designers to design and draw much earlier because they have to send it to the factory which is the kind of one of the phenomena around industrial buildings is it actually requires a lot more design earlier and that phenomenon is responsible for the the comfort with which we become as an industry lazy with steel and concrete we don't design it until it gets to site and then everything goes wrong and that's where the costs come up quite a lot so i think it has a second layer of benefit in terms of value certainly in europe we're seeing that so the supply and the specialist contractors are now associating with larger contractors to actually deliver that and then the last part of the saving is the lifespan you know there is a lot of saving in energy over time not just a sequestration of of timber but because there is a self-insulating thickness you do save on energy the problem they have is actually the houses are often just too warm in europe so there are there are layers of benefits that i think are making it very competitive and and we talk about it in value rather than cost yeah and honey fat also add time on site right the the construction schedule is is shortened um greatly i can see it from an example in portland oregon where i'm currently located um ben kaiser uh is building a kind of five-story um housing unit and at the same time they're putting like two cameras together for like concrete or and um wood frame construction and then the clt panels and if you measure the the amount of time both of those take with the same building same square footage um clt greatly reduces um your construction time and labor force on site well we have one last question before we need to wrap up our um session and the question is from chi kung lin how do you deal with renovations remodels and repairs over the life of the building we're already faced with that because if you go back certainly to the british way of constructing most of our houses have timber floors anyway so in simple terms the the the difference i suppose is that it's not carpentry clt is not like good old carpentry it does need specialist skill and specialist cutting tools and so on but it is actually jennifer can back this up it's easy to handle you can put windows in in the future you can re re-engage with it very quickly but it's really the supply you know can you get a new panel down the line and whether that's a problem or not in the states we don't know yet but it certainly isn't a problem here so it's developing let's say because some of the houses some of the schemes are only 10 or 15 years old but i can assure you that we can take them all down and recycle the whole building which we couldn't do before well thank you very much everyone for your questions thank you jennifer and hanif for this really interesting journey through your studio this past spring and i think it brings to light what will be a very popular uh movement going forward based on what i'm hearing from a lot of my colleagues around around the world you

Channel: Harvard GSD

Views: 7,732

Rating: 4.9790578 out of 5

Keywords:

Id: w2STKPvELD0

Length: 51min 25sec (3085 seconds)

Published: Tue Dec 08 2020