my grandfather taught me to work with wood when i was a little boy
and he also taught me the idea that if you cut down a tree to turn it into something honor that tree 's life and make it as beautiful as you
possibly can my little boy reminded me
that for all the technology and all the toys in the world sometimes just a small block of wood if you stack it up tall actually is an incredibly inspiring thing
these are my buildings i build all around the world out of our office in vancouver and new york
and we build buildings of different sizes and styles and different materials depending on where we are but wood is the material that i love the most and i 'm going to tell you the story about wood
but i 've actually seen that happen in a wood building i 've actually seen how people touch the wood and i think there 's a reason for it
just like snowflakes no two pieces of wood can ever be the same anywhere on earth that 's a wonderful thing i like to think that wood
gives mother nature fingerprints in our buildings
it 's mother nature 's fingerprints that make our buildings connect us to nature
down the coast here in california the redwood forest grows to forty stories tall
but the buildings that we think about in wood are only four stories tall in most places on earth
even building codes actually limit the ability for us to build
much taller than four stories in many places and that 's true here in the united states now there are exceptions but there needs to be some exceptions and things are going to change i 'm hoping and the reason i think that way is that today half of us live in cities
and that number is going to grow to seventy five percent
cities and density mean that our buildings are going to continue to be big
and i think there 's a role for wood to play in cities
and i feel that way because
three billion people in the world today over the next twenty years will need a new home
that 's forty percent of the world that are going to need a new building built for them in the next
twenty years now one in three people living in cities today actually live in a slum
a hundred million people in the world
cities are built in these two materials steel and concrete and they 're great materials they 're the materials of the last century
but they 're also materials with very high energy and very high greenhouse gas
emissions in their process
steel represents about three percent of man 's greenhouse gas emissions and concrete is over five percent
so if you think about that eight percent of our contribution to greenhouse gases today comes from those two materials alone
we don 't think about it a lot and unfortunately we actually don 't even think about buildings i think as much as we should this is a u s statistic about the impact of greenhouse gases
almost half of our greenhouse gases are related to the building industry and if we look at energy it 's the same story you 'll notice that transportation 's sort of second down that list but that 's the conversation we mostly hear about
and although a lot of that is about energy
it 's also so much about carbon
the problem i see is that ultimately the clash of how we solve that problem of serving those three billion people that need a home
and climate change are a head on collision about to happen or already happening
that challenge means that we have to start thinking in new ways and i think wood is going to be part of that solution and i 'm going to tell you the story of why as an architect wood is the only material big material that i can build with that 's already grown by the power of the sun
when a tree grows in the forest and gives off oxygen and soaks up carbon dioxide
and it dies and it falls to the forest floor
it gives that carbondioxide back to the atmosphere or into the ground if it burns in a forest fire it 's going to give that carbon back to the atmosphere as well
one cubic meter of wood
will store one tonne of carbon dioxide
now our two solutions to climate are obviously to reduce our emissions and find storage wood is the only major material building material i can build with that actually does both those two things
so i believe that we have
an ethic that the earth grows our food and we need to move to an ethic in this century that the earth should grow our homes
now how are we going to do that when we 're urbanizing at this rate and we think about wood buildings only at four stories we need to reduce the concrete and steel and we need to grow bigger and what we 've been working on is thirty story tall
buildings made of wood
we 've been engineering them with an engineer named eric karsh who works with me on it
and we 've been doing this new work because there are new wood products out there
for us to use and we call them mass timber panels these are panels made with young trees small growth trees small pieces of wood glued together to make panels that are enormous eight feet wide sixty four feet long and of various thicknesses
the way i describe this best i 've found is to say that we 're all used to two by four construction when we think about wood that 's what people jump to as a conclusion two by four construction is sort of like the little eight dot bricks of lego that we all played with as kids and you can make all kinds of cool things out of lego at that size and out of two by fours
but do remember when you were a kid and you kind of sifted through the pile in your basement and you found that big twenty four dot brick of lego and you were kind of like cool this is awesome i can build something really big and this is going to be great that 's the change
mass timber panels are those twenty four dot bricks they 're changing the scale of what we can do and what we 've developed is something we call fftt which is a creative commons solution to building
of building with these large panels where we tilt up six stories at a time if we want to
this animation shows you how the building goes together in a very simple way but these buildings are available for architects and engineers now to build on for different cultures in the world different architectural styles and characters in order for us
to build safely we 've engineered these buildings actually to work in a vancouver context where we 're a high seismic zone even at thirty stories tall
now obviously every time i bring this up people even you know here at the conference say are you serious thirty stories how 's that going to happen and there 's a lot of really
good questions that are asked and important questions that we spent quite a long time working on the answers to as we put together our report and the peer reviewed report i 'm just going to focus on a few of them and let 's start with fire because i think fire is probably the first one that you 're all thinking about right now fair enough and the way i describe it is this if i asked you to take a match and light it
and hold up a log and try to get that log to go on fire it doesn 't happen right we all know that but to build a fire you kind of start with small pieces of wood and you work your way up and eventually you can add the log to the fire
and when you do add the log to the fire of course it burns but it burns slowly
well mass timber panels these new products that we 're using are much like the log it 's hard to start them on fire and when they do they actually burn extraordinarily predictably and we can use fire science in order to predict and make these buildings as safe as concrete and as safe as steel
the next big issue deforestation eighteen percent of our
contribution to greenhouse gas emissions worldwide is the result of deforestation the last thing we want to do is cut down trees
or the last thing we want to do is cut down the wrong trees
there are models for sustainable forestry that allow us to cut trees properly and those are the only trees appropriate to use for these kinds of systems now i actually think that these ideas will change the economics of deforestation
in countries with deforestation issues we need to find a way to provide better value for the forest and actuallyencourage people to make money through very fast growth cycles ten twelve fifteen year old trees that make these products and allow us to build at this scale
we 've calculated a twenty story building we 'll grow enough wood in north america every thirteen minutes
that 's how much it takes
the carbon story here is a really good one
if we built a twenty story building out of cement and concrete the process would result in the manufacturing of that cement and one thousand two hundred tonnes of carbondioxide if we did it in wood in this solution we 'd sequester about three thousand one hundred tonnes for a net difference of four thousand three
hundred tonnes that 's the equivalent of about nine hundred cars removed from the road in one year
think back to that three billion people that need a new home and maybe this is a contributor to reducing we 're at the beginning of a revolution i hope in the way we build because this is the first new way to build a skyscraper in probably one hundred years or more
but the challenge is changing society 's perception of possibility and it 's a huge challenge the engineering is truthfully the easy part of this
and the way i describe it is this the first skyscraper technically and the definition of a skyscraper is ten stories tall believe it or not but the first skyscraper was this one in chicago and people were terrified to walk underneath this building
but only four years after it was built gustave eiffel was building the eiffel tower
and as he built the eiffel tower he changed the skylines of the cities of the world
changed and created a competition between places like new york city and chicago where developers started building bigger and bigger buildings and pushing the envelope up higher and higher with better and better engineering
we built this model in new york actually as a theoretical model on the campus of a technical university soon to come and the reason we picked this site to just show you what these buildings may look like because the exterior can change it 's really just the structure that we 're talking about
the reason we picked it is because this is a technical university and i believe that wood is the most technologically advanced material i can build with
but that 's the way it should be nature 's fingerprints in the built environment
i 'm looking for this opportunity to create an eiffel tower
we call it buildings are starting to go up around the world there 's a building in london that 's nine stories a new building that just finished in australia that i believe is ten or eleven we 're starting to push the height up of
in the not so distant future
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