1 00:00:03,451 --> 00:00:04,314 Narrator: How does this incredible skyscraper 2 00:00:04,315 --> 00:00:06,626 defy the laws of physics? 3 00:00:06,627 --> 00:00:08,787 Man: This house always is on the verge of falling down. 4 00:00:09,561 --> 00:00:12,288 Narrator: What happens when one of the world's richest men 5 00:00:13,185 --> 00:00:15,567 and its most extreme architect 6 00:00:16,326 --> 00:00:17,672 create the impossible? 7 00:00:19,053 --> 00:00:20,191 Man: Obviously we know that levitation of buildings 8 00:00:20,192 --> 00:00:22,194 hasn't been invented yet. 9 00:00:23,678 --> 00:00:24,713 Narrator: And how do you build a 1,000-foot-high elevator 10 00:00:24,714 --> 00:00:27,510 in an area so remote, 11 00:00:28,407 --> 00:00:29,822 heavy machinery can't be used? 12 00:00:33,688 --> 00:00:35,208 This is the age of the extraordinary... 13 00:00:36,760 --> 00:00:39,522 Man: Where else can you swim from one skyscraper to the other 14 00:00:40,247 --> 00:00:44,146 300 feet in the air? 15 00:00:44,147 --> 00:00:45,627 Narrator: Where ingenious engineers 16 00:00:46,184 --> 00:00:47,701 have unleashed unchecked creativity... 17 00:00:47,702 --> 00:00:51,188 Woman: Everything in this building 18 00:00:51,189 --> 00:00:52,534 pushes at the boundaries of what's possible. 19 00:00:52,535 --> 00:00:53,960 Narrator: Building structures so outrageous, 20 00:00:53,984 --> 00:00:56,125 they defy logic. 21 00:00:56,987 --> 00:00:58,850 Woman: The forces on this thing 22 00:00:58,851 --> 00:01:00,266 look like it should be torn apart. 23 00:01:00,267 --> 00:01:02,269 Narrator: Now their secrets revealed. 24 00:01:03,718 --> 00:01:06,169 Discovering the incredible stories of their construction... 25 00:01:07,584 --> 00:01:09,724 Woman: These are extraordinary feats of engineering. 26 00:01:10,760 --> 00:01:13,521 Narrator: To try and understand 27 00:01:14,246 --> 00:01:15,868 how did they build that? 28 00:01:20,183 --> 00:01:23,635 New York's Manhattan island, 29 00:01:24,705 --> 00:01:26,145 where the skyscraper rules the roost. 30 00:01:30,124 --> 00:01:32,194 Ever since the first one went up over a century ago, 31 00:01:32,195 --> 00:01:34,439 the drive has been to push towers taller and cheaper. 32 00:01:36,544 --> 00:01:39,271 But the resulting demands on engineers 33 00:01:40,479 --> 00:01:42,199 have created repetitive, predictable shapes. 34 00:01:43,344 --> 00:01:46,829 Creative flair and groundbreaking design 35 00:01:46,830 --> 00:01:49,247 were rare exceptions. 36 00:01:49,971 --> 00:01:52,250 That was until 2017, 37 00:01:53,423 --> 00:01:54,863 when in Manhattan's Tribeca district, 38 00:01:55,701 --> 00:01:57,910 a spectacular new tower was unveiled. 39 00:02:01,949 --> 00:02:03,744 This is 56 Leonard street, 40 00:02:05,021 --> 00:02:07,748 where a team of engineers and architects 41 00:02:08,645 --> 00:02:10,751 stepped over the cutting edge, 42 00:02:11,890 --> 00:02:13,290 ripping up the skyscraper rule book. 43 00:02:17,206 --> 00:02:18,447 Woman: The shapes are extraordinary... 44 00:02:18,448 --> 00:02:20,449 Boxes stacked on one another. 45 00:02:20,450 --> 00:02:21,693 And some of them are slid out. 46 00:02:22,763 --> 00:02:24,004 The whole thing looks so precarious. 47 00:02:24,005 --> 00:02:26,284 Narrator: At Leonard street, 48 00:02:27,147 --> 00:02:29,355 56 stories of unique apartments 49 00:02:29,356 --> 00:02:31,836 are stacked ever more daringly right up to its 820-foot summit. 50 00:02:33,981 --> 00:02:36,880 Here at the top, 51 00:02:38,192 --> 00:02:39,261 engineering logic seems to have been recalibrated 52 00:02:39,262 --> 00:02:43,127 to defy the laws of gravity. 53 00:02:43,128 --> 00:02:45,199 Woman: It all just looks a bit scary. 54 00:02:49,376 --> 00:02:51,816 Narrator: Unique apartments with sky-high impossible overhangs 55 00:02:53,483 --> 00:02:56,176 created a complex and expensive construction. 56 00:02:58,143 --> 00:03:00,973 So, how did they build it? 57 00:03:04,563 --> 00:03:06,772 Even more than most cities, 58 00:03:07,601 --> 00:03:10,430 Manhattan is space-hungry, 59 00:03:10,431 --> 00:03:12,271 resulting in tall buildings with simple layouts 60 00:03:13,054 --> 00:03:15,884 that are a compromise between the engineering challenge 61 00:03:15,885 --> 00:03:18,715 of building a skyscraper 62 00:03:20,061 --> 00:03:22,061 and the practical economics of doing it at a price. 63 00:03:22,685 --> 00:03:25,481 Nehemiah mabry: Most skyscrapers and tall buildings 64 00:03:26,551 --> 00:03:27,931 are either rectangular or tubular 65 00:03:29,070 --> 00:03:30,670 because those are really efficient shapes 66 00:03:31,314 --> 00:03:32,834 when it comes to supporting themselves. 67 00:03:33,765 --> 00:03:36,249 Joshua macabuag: For construction purposes, 68 00:03:36,250 --> 00:03:38,182 developers like to have buildings be fairly regular 69 00:03:38,183 --> 00:03:39,863 and columns going straight down, et cetera, 70 00:03:40,254 --> 00:03:41,807 @so that every floor is the same 71 00:03:43,084 --> 00:03:44,706 and they can just build it nice and quickly. 72 00:03:44,707 --> 00:03:47,107 Narrator: These uniform layouts are now so efficient to build 73 00:03:47,779 --> 00:03:50,506 that a conventional high-rise with over 50 floors 74 00:03:51,610 --> 00:03:54,441 can be completed in just weeks. 75 00:03:55,752 --> 00:03:57,672 But the results are often a little underwhelming. 76 00:03:59,825 --> 00:04:02,621 Woman: Imagine, you wanted to change things up a bit. 77 00:04:04,105 --> 00:04:06,280 Ellie cosgrave: You could put this cantilevered section 78 00:04:06,867 --> 00:04:09,144 in there... 79 00:04:09,145 --> 00:04:11,008 This box section in there. 80 00:04:11,009 --> 00:04:12,889 And you might want to even like take out bits... 81 00:04:13,977 --> 00:04:16,220 Oops. 82 00:04:16,221 --> 00:04:17,808 Narrator: Changing it up 83 00:04:17,809 --> 00:04:18,672 in the world of skyscraper construction 84 00:04:18,673 --> 00:04:20,639 means taking risks. 85 00:04:22,020 --> 00:04:24,140 But that wasn't going to stop developer izak senbahar. 86 00:04:25,920 --> 00:04:28,647 Izak senbahar: We knew this was gonna be a very tall structure 87 00:04:29,993 --> 00:04:32,548 and very visible from almost every angle in the city. 88 00:04:33,825 --> 00:04:36,724 So we said, ok, 89 00:04:37,932 --> 00:04:39,812 we have a responsibility to do something iconic. 90 00:04:43,697 --> 00:04:45,423 We didn't want something repetitive, 91 00:04:46,286 --> 00:04:47,942 some just straight up building. 92 00:04:49,116 --> 00:04:51,360 We wanted something more interesting, 93 00:04:51,946 --> 00:04:54,466 more sculptured. 94 00:04:57,193 --> 00:05:00,022 Narrator: When izak bought the site in 2008, 95 00:05:00,023 --> 00:05:02,923 Tribeca was not one of Manhattan's 96 00:05:03,786 --> 00:05:05,066 glamorous residential districts. 97 00:05:08,377 --> 00:05:09,584 But building something special anywhere in New York 98 00:05:09,585 --> 00:05:12,415 is expensive, 99 00:05:13,865 --> 00:05:15,945 so these apartments would have to command top dollar. 100 00:05:20,596 --> 00:05:22,556 Needing a design that would attract the uber rich, 101 00:05:23,702 --> 00:05:26,464 izak headed to Europe 102 00:05:27,499 --> 00:05:28,603 and world-renowned Swiss architects 103 00:05:28,604 --> 00:05:30,537 herzog and De meuron. 104 00:05:31,745 --> 00:05:33,262 Jacques herzog: We felt that izak was ready 105 00:05:33,263 --> 00:05:35,576 for a new approach, 106 00:05:36,301 --> 00:05:38,233 a more radical approach. 107 00:05:38,234 --> 00:05:40,477 Narrator: Herzog and De meuron's portfolio 108 00:05:40,478 --> 00:05:42,078 includes some truly incredible buildings, 109 00:05:42,687 --> 00:05:45,345 like bayern Munich's arena stadium 110 00:05:46,484 --> 00:05:48,451 and London's Tate modern extension. 111 00:05:49,694 --> 00:05:52,490 But no skyscrapers. 112 00:05:55,872 --> 00:05:56,563 Jacques: Even if we had done a building before, 113 00:05:56,564 --> 00:05:58,358 a tall building, 114 00:05:59,704 --> 00:06:00,911 we would always look at it from a different angle 115 00:06:00,912 --> 00:06:03,363 and would give him something unexpected. 116 00:06:05,537 --> 00:06:09,160 We want it to be a stack of apartments 117 00:06:09,161 --> 00:06:12,543 but not an anonymous one. 118 00:06:12,544 --> 00:06:15,064 The building could be understood as a pile of individual pieces, 119 00:06:16,306 --> 00:06:19,757 even in the middle part, 120 00:06:19,758 --> 00:06:21,588 and then the top, 121 00:06:22,934 --> 00:06:24,590 which would have even more exclusive apartments 122 00:06:24,591 --> 00:06:26,831 which we decided could become like stacked private homes. 123 00:06:27,801 --> 00:06:30,597 And I think that's really new 124 00:06:31,701 --> 00:06:33,141 and hadn't been done before anywhere. 125 00:06:34,394 --> 00:06:35,946 Narrator: There's good reason it's never been done before. 126 00:06:35,947 --> 00:06:38,467 In order to make a strong, stable building, 127 00:06:39,502 --> 00:06:43,229 irregular spaces are normally built 128 00:06:43,230 --> 00:06:44,921 into the super stable lower floors, 129 00:06:45,991 --> 00:06:47,993 with smaller structures at the top. 130 00:06:49,478 --> 00:06:51,718 The architect concept that the higher the apartments are, 131 00:06:52,170 --> 00:06:55,000 the more off-balance they appear, 132 00:06:56,381 --> 00:06:58,541 flipped conventional high-rise engineering on its head. 133 00:07:03,561 --> 00:07:05,872 To pull this trick off at the top, 134 00:07:05,873 --> 00:07:08,082 they needed to reduce 135 00:07:09,187 --> 00:07:10,739 structural complexity lower down, 136 00:07:10,740 --> 00:07:12,820 while still making the floors appear to be different. 137 00:07:14,123 --> 00:07:16,884 To do this, they hatched an ingenious plan. 138 00:07:19,197 --> 00:07:21,924 The first 46 floors would be built in the conventional way, 139 00:07:23,822 --> 00:07:26,584 using continuous outer columns and inner walls 140 00:07:27,930 --> 00:07:30,691 to provide support for the floors above. 141 00:07:31,830 --> 00:07:34,005 The floor layouts would also repeat, 142 00:07:35,178 --> 00:07:36,658 but they'd be made to appear different 143 00:07:37,940 --> 00:07:40,180 by changing the size and position of balconies and edges. 144 00:07:41,253 --> 00:07:44,153 The 46th floor would be unoccupied 145 00:07:45,395 --> 00:07:47,235 and so could be packed with load-bearing walls, 146 00:07:48,019 --> 00:07:51,022 creating a 47th floor plate 147 00:07:52,402 --> 00:07:54,362 that would be super-strong, super-stable platform. 148 00:07:58,995 --> 00:08:01,791 Skyscraper specialist hezi mena 149 00:08:03,310 --> 00:08:05,550 was the structural engineer tasked with making it happen. 150 00:08:06,865 --> 00:08:09,558 Hezi mena: We tried to stiffen up the building enough 151 00:08:10,317 --> 00:08:12,768 up to the 46th floor. 152 00:08:13,631 --> 00:08:15,321 So when we reach the 47th floor, 153 00:08:15,322 --> 00:08:18,014 the first sky villa, 154 00:08:19,257 --> 00:08:20,937 the building will have sufficient stiffness 155 00:08:21,224 --> 00:08:22,571 @that we can have the flexibility 156 00:08:23,744 --> 00:08:25,504 of doing whatever we want structurally 157 00:08:25,505 --> 00:08:28,231 and give the architect the freedom 158 00:08:29,267 --> 00:08:30,787 to do whatever he wants with the space. 159 00:08:33,789 --> 00:08:35,349 Narrator: And what the architects wanted 160 00:08:35,998 --> 00:08:38,000 was to create an extraordinary visual effect. 161 00:08:40,105 --> 00:08:42,901 Jacques: If you make this upper box, 162 00:08:43,971 --> 00:08:46,007 let's say, hover to a certain degree, 163 00:08:46,008 --> 00:08:47,568 you don't make it hover so it collapses. 164 00:08:48,424 --> 00:08:51,253 You can push it to an extreme, you know, 165 00:08:51,254 --> 00:08:53,740 like in chaplin's movie, you know, 166 00:08:55,086 --> 00:08:57,286 where this house always is on the verge of falling down. 167 00:08:58,330 --> 00:09:01,126 Together with the structural engineer, 168 00:09:02,542 --> 00:09:03,714 you find the right moment between something fragile, 169 00:09:03,715 --> 00:09:06,338 something even dangerous. 170 00:09:10,826 --> 00:09:12,666 Narrator: The vision for off-balance apartments 171 00:09:13,449 --> 00:09:15,209 that still had wraparound views 172 00:09:16,417 --> 00:09:18,177 meant pushing structural concrete engineering 173 00:09:18,523 --> 00:09:20,698 right to the edge. 174 00:09:21,284 --> 00:09:23,804 The lower floors 175 00:09:24,978 --> 00:09:26,323 used conventional skyscraper engineering, 176 00:09:26,324 --> 00:09:29,464 where continuous columns share the load. 177 00:09:29,465 --> 00:09:32,122 But because the top nine floors are all offset, 178 00:09:32,123 --> 00:09:34,953 that same system wouldn't work. 179 00:09:36,196 --> 00:09:38,060 Each of these floors has to be stiff enough 180 00:09:39,130 --> 00:09:41,959 to support huge cantilevered overhangs, 181 00:09:41,960 --> 00:09:44,722 some over 23 feet. 182 00:09:45,446 --> 00:09:47,725 And they had to do that 183 00:09:48,967 --> 00:09:49,865 without compromising the view from within. 184 00:09:49,866 --> 00:09:52,661 To pull it off, 185 00:09:53,731 --> 00:09:55,371 engineers turned to a 125-year-old idea... 186 00:09:55,698 --> 00:09:59,770 The vierendeel truss. 187 00:09:59,771 --> 00:10:02,014 A regular truss uses diagonal cross members 188 00:10:02,015 --> 00:10:04,776 to create triangles 189 00:10:06,157 --> 00:10:08,317 that make it very strong both laterally and vertically. 190 00:10:08,366 --> 00:10:11,162 But the views from within would be ruined. 191 00:10:11,852 --> 00:10:15,648 A vierendeel truss 192 00:10:15,649 --> 00:10:17,236 connects the two floors using only vertical columns. 193 00:10:17,237 --> 00:10:19,964 So it's just as strong vertically 194 00:10:21,034 --> 00:10:22,863 and it keeps its lateral strength 195 00:10:24,313 --> 00:10:26,210 through the massively strong central lift shaft column 196 00:10:26,211 --> 00:10:29,007 that also connects the floors. 197 00:10:30,250 --> 00:10:32,803 So the vierendeel truss allows huge openings, 198 00:10:32,804 --> 00:10:35,289 and the apartments above can be offset with crazy overhangs. 199 00:10:38,499 --> 00:10:41,226 Nehemiah: A vierendeel truss is actually a brilliant solution 200 00:10:41,986 --> 00:10:44,713 for a long cantilever. 201 00:10:45,955 --> 00:10:47,162 They were developed by Arthur vierendeel, 202 00:10:47,163 --> 00:10:49,406 a 19th-century Belgian engineer 203 00:10:49,407 --> 00:10:51,788 who developed this super strong truss 204 00:10:51,789 --> 00:10:53,389 particularly resistant to bending forces. 205 00:10:54,412 --> 00:10:56,725 Hezi: The advantage of utilizing a vierendeel truss 206 00:10:57,933 --> 00:10:59,900 is that it's not obstructive architecturally. 207 00:11:00,729 --> 00:11:05,077 A traditional truss 208 00:11:05,078 --> 00:11:07,278 would have a diagonal member crossing through the space, 209 00:11:07,356 --> 00:11:10,083 and that would be very obstructive architecturally 210 00:11:10,808 --> 00:11:13,464 and kind of prohibitive, 211 00:11:13,465 --> 00:11:15,294 so we came with a different approach. 212 00:11:15,295 --> 00:11:17,677 Narrator: So this is how the vierendeel truss 213 00:11:18,919 --> 00:11:20,559 became the key to building the sky villas. 214 00:11:21,128 --> 00:11:23,821 On super stable floor 47, 215 00:11:24,891 --> 00:11:27,720 concrete columns are precisely placed 216 00:11:27,721 --> 00:11:29,999 where they will give support to the floor above. 217 00:11:31,207 --> 00:11:32,899 This creates the first vierendeel truss. 218 00:11:34,245 --> 00:11:37,626 The central lift shaft provides all the lateral strength 219 00:11:37,627 --> 00:11:41,803 so the floor remains beautifully open plan, 220 00:11:41,804 --> 00:11:43,844 but can still support the tremendous downward forces 221 00:11:45,014 --> 00:11:47,707 from the eight unique stories built on top. 222 00:11:48,811 --> 00:11:51,020 These trusses create such rigidity 223 00:11:51,780 --> 00:11:54,230 that the upper floors 224 00:11:55,576 --> 00:11:56,611 don't have to sit directly on top of one another, 225 00:11:56,612 --> 00:11:59,028 allowing the amazing overhangs, 226 00:12:00,133 --> 00:12:01,997 all helping to make the sky villas 227 00:12:03,343 --> 00:12:05,223 some of the most spectacular homes in the world. 228 00:12:05,345 --> 00:12:08,106 Hezi: There's literally nothing underneath us 229 00:12:08,831 --> 00:12:10,212 other than the slab. 230 00:12:11,558 --> 00:12:13,110 And then it's straight down to the street level, 231 00:12:13,111 --> 00:12:17,011 800 feet below us. 232 00:12:17,012 --> 00:12:18,772 Narrator: Not only are they over 650 feet up, 233 00:12:20,912 --> 00:12:24,604 at up to 5,900 square feet, 234 00:12:24,605 --> 00:12:26,918 the nine sky villas are huge, 235 00:12:28,126 --> 00:12:30,922 each exclusively occupying its own floor, 236 00:12:31,820 --> 00:12:34,339 and each with a unique layout. 237 00:12:35,616 --> 00:12:37,377 Situated in up-and-coming midtown Manhattan, 238 00:12:38,792 --> 00:12:41,243 it was hoped homes here would fetch sky-high prices. 239 00:12:42,934 --> 00:12:47,006 Hayley loren oakes: This is a building 240 00:12:47,007 --> 00:12:49,043 @aimed at some of the wealthiest people in New York. 241 00:12:49,044 --> 00:12:51,460 Narrator: The lower apartments up to the 45th floor 242 00:12:52,806 --> 00:12:54,843 would be priced between $3 million and $10 million, 243 00:12:56,672 --> 00:12:59,399 while the plan was the sky villas would sell 244 00:13:00,158 --> 00:13:03,885 for over $20 million. 245 00:13:03,886 --> 00:13:06,026 And those hefty price tags were needed, 246 00:13:07,200 --> 00:13:08,960 as it became clear the top nine floors, 247 00:13:09,789 --> 00:13:12,032 with their unique layouts, 248 00:13:13,275 --> 00:13:15,035 were going to be slow and expensive to build. 249 00:13:15,622 --> 00:13:18,349 Izak: You know, you do three, four floors 250 00:13:19,108 --> 00:13:21,489 of all the same thing, 251 00:13:21,490 --> 00:13:22,697 and then you're used to it, then it's just automatic. 252 00:13:22,698 --> 00:13:24,578 Narrator: But of course herzog's nine sky villas 253 00:13:24,838 --> 00:13:27,047 were all unique. 254 00:13:28,531 --> 00:13:30,731 Hayley: Every floor plate is a different size and shape. 255 00:13:30,879 --> 00:13:34,951 Izak: So every floor, there was a learning curve, 256 00:13:34,952 --> 00:13:37,471 and then you learn that, and now it's a new plan. 257 00:13:38,300 --> 00:13:40,198 It's just like, you know, 258 00:13:41,303 --> 00:13:43,545 the game changed every time we poured. 259 00:13:43,546 --> 00:13:46,963 Narrator: Because each of the sky villas is different, 260 00:13:46,964 --> 00:13:49,483 before work could start on the apartment above, 261 00:13:50,933 --> 00:13:53,093 the one below needed to be strong enough to support it. 262 00:13:53,729 --> 00:13:56,628 And that meant more time for the concrete to set. 263 00:14:01,737 --> 00:14:04,083 Hezi: The biggest challenge for the contractor 264 00:14:04,084 --> 00:14:06,190 is to hold the forms and scaffoldings in place 265 00:14:08,537 --> 00:14:11,367 until the concrete cures and reach its required strength, 266 00:14:13,369 --> 00:14:16,165 and then he can remove the scaffolding 267 00:14:17,028 --> 00:14:18,305 and the temporary supports. 268 00:14:19,168 --> 00:14:21,583 Izak: You know, in New York, 269 00:14:21,584 --> 00:14:23,240 we're used to pouring one floor every other day, 270 00:14:23,241 --> 00:14:25,312 here some floors took six weeks. 271 00:14:26,003 --> 00:14:28,970 Narrator: By 2014, 272 00:14:28,971 --> 00:14:31,076 the lower 46 floors had taken 20 months to complete. 273 00:14:31,077 --> 00:14:33,976 And with the top nine floors set to take nine more months, 274 00:14:35,115 --> 00:14:37,877 extra measures were taken 275 00:14:39,085 --> 00:14:40,671 to make the site safe and weatherproof. 276 00:14:40,672 --> 00:14:43,089 Hezi: It was actually very interesting 277 00:14:43,917 --> 00:14:46,194 to see during construction 278 00:14:46,195 --> 00:14:47,955 that it had this black curtain protection 279 00:14:47,956 --> 00:14:50,406 around the entire 10 floors. 280 00:14:51,200 --> 00:14:53,996 Once everything cured, 281 00:14:55,170 --> 00:14:56,687 they start stripping down the scaffolding, 282 00:14:56,688 --> 00:14:58,414 and then this beautiful structure, 283 00:14:59,312 --> 00:15:00,520 it's almost like a sculpture, 284 00:15:01,486 --> 00:15:02,694 revealed itself to the public. 285 00:15:05,490 --> 00:15:07,250 Narrator: So with Patience and engineering ingenuity, 286 00:15:07,251 --> 00:15:09,978 the impossible overhanging sky villas had been created. 287 00:15:12,359 --> 00:15:15,190 But before anyone moved in, 288 00:15:16,087 --> 00:15:17,295 the building needed protection 289 00:15:18,400 --> 00:15:19,952 from something that spells trouble 290 00:15:19,953 --> 00:15:21,643 for any skyscraper... 291 00:15:21,644 --> 00:15:23,336 The wind. 292 00:15:24,751 --> 00:15:26,234 Joshua: Tall buildings will always move in the wind, 293 00:15:26,235 --> 00:15:27,875 and that can't ever be completely stopped, 294 00:15:28,030 --> 00:15:29,997 and they'll always move... 295 00:15:29,998 --> 00:15:31,308 In some cases, by quite a lot. 296 00:15:31,309 --> 00:15:32,749 Narrator: New York has recorded winds 297 00:15:33,380 --> 00:15:35,588 of up to 100 miles per hour, 298 00:15:35,589 --> 00:15:37,246 and Leonard street's sheer height 299 00:15:38,558 --> 00:15:40,318 and comparative isolation from other scrapers 300 00:15:40,940 --> 00:15:43,260 means in high winds it can move by up to a foot at the top. 301 00:15:46,221 --> 00:15:49,017 It's engineered to handle this amount of movement, 302 00:15:49,741 --> 00:15:52,227 but left unchecked, 303 00:15:53,297 --> 00:15:55,229 these movements can keep on increasing, 304 00:15:55,230 --> 00:15:57,679 potentially collapsing the building. 305 00:15:57,680 --> 00:16:00,269 So it's crucial there's something 306 00:16:01,132 --> 00:16:03,306 to counteract these forces. 307 00:16:03,307 --> 00:16:05,240 Corina kwami: A lot of skyscrapers 308 00:16:06,103 --> 00:16:08,276 have what's called mass dampers. 309 00:16:08,277 --> 00:16:09,557 They're basically counterweights. 310 00:16:10,693 --> 00:16:12,867 So, for example, if the wind is pushing one way, 311 00:16:12,868 --> 00:16:15,215 the counterweight pushes the other way. 312 00:16:16,423 --> 00:16:18,804 Narrator: Most skyscraper counterweights 313 00:16:18,805 --> 00:16:20,772 are large suspended blocks like this. 314 00:16:22,084 --> 00:16:26,260 But at Leonard street, 315 00:16:26,261 --> 00:16:27,778 they chose a damper system sometimes used to cope 316 00:16:27,779 --> 00:16:30,230 with the ultimate threat to buildings... 317 00:16:30,817 --> 00:16:33,130 Earthquakes. 318 00:16:34,338 --> 00:16:37,029 Skyscrapers in earthquake zones have water tanks 319 00:16:37,030 --> 00:16:39,377 to cope with the swaying induced by a massive quake. 320 00:16:40,620 --> 00:16:43,381 This is what 56 Leonard street uses. 321 00:16:44,865 --> 00:16:47,558 Hayley: At the top is a giant a tank of water. 322 00:16:48,766 --> 00:16:52,148 When the building moves one way due to the wind, 323 00:16:52,149 --> 00:16:54,269 the water in the tank moves in the opposite direction. 324 00:16:55,255 --> 00:16:58,051 Narrator: So 56 Leonard street 325 00:16:59,190 --> 00:17:00,550 was ready for the forces of nature. 326 00:17:04,195 --> 00:17:05,675 But in 2016, just a year from opening, 327 00:17:07,026 --> 00:17:10,407 the engineers needed to get the inside prepared 328 00:17:10,408 --> 00:17:13,135 for new residents. 329 00:17:14,619 --> 00:17:17,179 To do this, a twist was given to an otherwise ordinary feature... 330 00:17:19,176 --> 00:17:22,764 The lobby staircase. 331 00:17:22,765 --> 00:17:25,492 Herzog: You have a stair, 332 00:17:27,011 --> 00:17:28,391 so do the stair in the way that it's nice to walk up and down. 333 00:17:28,392 --> 00:17:30,566 It's inviting, I would say, to take the stairs 334 00:17:31,774 --> 00:17:33,604 if it's one, two, three floors perhaps. 335 00:17:34,639 --> 00:17:36,572 Narrator: As usual at 56 Leonard, 336 00:17:37,780 --> 00:17:39,500 the stairs would be made of poured concrete. 337 00:17:40,852 --> 00:17:43,372 Debbie sterling: So the way to design something in concrete, 338 00:17:44,132 --> 00:17:46,375 it's called form work, 339 00:17:47,100 --> 00:17:49,308 and it's really simple. 340 00:17:49,309 --> 00:17:50,241 It's basically just creating a mold 341 00:17:50,242 --> 00:17:51,691 of whatever shape you want 342 00:17:52,899 --> 00:17:54,244 and pouring the concrete in, letting it dry, 343 00:17:54,245 --> 00:17:55,695 and there you have it. 344 00:17:56,420 --> 00:17:58,284 Narrator: Sounds simple, 345 00:17:59,768 --> 00:18:01,968 except when the pour involves nearly 50 tons of concrete 346 00:18:02,702 --> 00:18:05,463 and the architect is demanding a seamless finish 347 00:18:06,050 --> 00:18:08,259 for his stairs. 348 00:18:09,122 --> 00:18:11,537 A seamless finish is created 349 00:18:11,538 --> 00:18:13,125 by not letting the concrete set between pours, 350 00:18:13,126 --> 00:18:17,095 so preparations needed to be meticulous. 351 00:18:17,096 --> 00:18:20,512 Hayley: It took five months to plan the stairs 352 00:18:20,513 --> 00:18:22,170 and create the mold 353 00:18:23,378 --> 00:18:24,999 that the concrete would be poured into. 354 00:18:25,000 --> 00:18:27,281 Izak: It started with experts conducting the whole pouring 355 00:18:27,416 --> 00:18:30,901 because concrete has air bubbles in it, 356 00:18:30,902 --> 00:18:32,490 and that's why they use vibrators. 357 00:18:33,560 --> 00:18:35,183 This guy was conducting everybody 358 00:18:36,011 --> 00:18:38,046 where to use the vibrator. 359 00:18:38,047 --> 00:18:39,991 It was a very, very precise operation and a long day. 360 00:18:40,015 --> 00:18:43,983 Narrator: The carefully poured staircase 361 00:18:43,984 --> 00:18:45,848 was typical of the attention lavished 362 00:18:46,677 --> 00:18:48,196 on every inch of this building. 363 00:18:49,300 --> 00:18:53,338 Once finished in 2017, 364 00:18:53,339 --> 00:18:54,979 the quality of Leonard street was obvious. 365 00:18:56,273 --> 00:19:00,276 But potential buyers 366 00:19:00,277 --> 00:19:01,001 had understood this was a special building 367 00:19:01,002 --> 00:19:03,521 way before that. 368 00:19:06,317 --> 00:19:07,593 Sales had opened in 2013, 369 00:19:07,594 --> 00:19:11,252 and almost immediately 370 00:19:11,253 --> 00:19:13,293 someone agreed to pay $47 million for a sky villa... 371 00:19:14,325 --> 00:19:16,948 A record for any address below midtown Manhattan, 372 00:19:18,743 --> 00:19:21,505 and a sign that the risks taken by its developer, 373 00:19:22,126 --> 00:19:25,473 izak senbahar, 374 00:19:25,474 --> 00:19:27,372 would pay off. 375 00:19:27,373 --> 00:19:29,546 Izak: I think we broke a record. 376 00:19:29,547 --> 00:19:30,823 We sold close to a billion dollars 377 00:19:30,824 --> 00:19:32,722 in nine months. 378 00:19:32,723 --> 00:19:34,311 Narrator: 2.5 million man hours, 379 00:19:35,415 --> 00:19:37,728 nearly 100,000 cubic feet of concrete, 380 00:19:38,591 --> 00:19:41,628 and 5,000 tons of steel 381 00:19:42,664 --> 00:19:44,321 went into creating Leonard street's 382 00:19:45,460 --> 00:19:46,770 half a million square feet of space. 383 00:19:46,771 --> 00:19:49,567 It had taken over five years, 384 00:19:50,913 --> 00:19:53,073 but a towering landmark now graced Manhattan's skyline. 385 00:19:54,054 --> 00:19:56,781 And if proof of its success was needed, 386 00:19:58,093 --> 00:19:59,933 locals have affectionately given 56 a nickname. 387 00:20:02,373 --> 00:20:06,618 Jacques: Someone spoke of the jenga tower. 388 00:20:06,619 --> 00:20:08,171 At the beginning, I didn't even know what he was talking about, 389 00:20:08,172 --> 00:20:09,863 but, um, people like it, and, um... 390 00:20:11,037 --> 00:20:13,660 If people like it over a certain time, 391 00:20:14,489 --> 00:20:16,317 this is a good, good sign. 392 00:20:16,318 --> 00:20:20,010 Izak: It was difficult. 393 00:20:20,011 --> 00:20:21,495 It was 10 years of my life. 394 00:20:21,496 --> 00:20:22,428 But to build a building like that in the skyline, 395 00:20:22,429 --> 00:20:24,361 it always feels good 396 00:20:25,707 --> 00:20:27,190 that, you know, you've built something like that 397 00:20:27,191 --> 00:20:31,436 corina: 56 Leonard is remarkable. 398 00:20:31,437 --> 00:20:33,092 I mean, it stretches the limit of what's possible to build, 399 00:20:33,093 --> 00:20:35,786 what's structurally possible, 400 00:20:36,614 --> 00:20:37,891 and then celebrates that. 401 00:20:42,033 --> 00:20:43,310 Narrator: 12,000 miles from the ma 402 00:20:43,311 --> 00:20:46,037 of Manhattan 403 00:20:48,143 --> 00:20:52,422 are mother nature's skyscrapers. 404 00:20:52,423 --> 00:20:54,667 The towering sandstone columns and miniature rainforests 405 00:20:56,151 --> 00:20:58,981 of zhangjiajie national park in central China 406 00:21:00,051 --> 00:21:02,847 are a unique spectacle on planet earth. 407 00:21:04,677 --> 00:21:07,438 Corina: This is a unesco world heritage site. 408 00:21:08,508 --> 00:21:09,788 Beautiful yet strange landscape. 409 00:21:10,579 --> 00:21:12,443 There's nowhere else like it. 410 00:21:13,272 --> 00:21:14,997 Narrator: Unsurprisingly, 411 00:21:15,998 --> 00:21:17,930 millions of people want to see it, 412 00:21:17,931 --> 00:21:20,051 and what's the best way to enjoy that incredible view? 413 00:21:21,694 --> 00:21:24,386 By taking the world's tallest outdoor elevator. 414 00:21:25,870 --> 00:21:28,597 The 1,000-foot-high elevator of a hundred dragons 415 00:21:30,047 --> 00:21:32,981 is better known as the bailong elevator. 416 00:21:37,434 --> 00:21:40,022 Joshua: This is the elevator 417 00:21:41,092 --> 00:21:42,852 that hangs off the side of a cliff. 418 00:21:42,853 --> 00:21:44,232 It's taller than the Eiffel Tower, 419 00:21:44,233 --> 00:21:46,338 taller than the shard in London. 420 00:21:46,339 --> 00:21:47,789 Narrator: The site was so remote 421 00:21:49,169 --> 00:21:51,089 that heavy machines couldn't be used to build it. 422 00:21:51,551 --> 00:21:53,795 All the work had to be done by hand. 423 00:21:54,968 --> 00:21:57,592 Hayley: It carries 1,380 passengers an hour 424 00:21:59,283 --> 00:22:03,321 and all in the middle of an earthquake zone. 425 00:22:03,322 --> 00:22:05,910 Narrator: But laser systems and escape tunnels 426 00:22:07,153 --> 00:22:08,993 keep the tourists safe from the seismic danger. 427 00:22:10,432 --> 00:22:14,435 Debbie: And if you don't want to take the elevator, 428 00:22:14,436 --> 00:22:16,436 you can just go ahead and take the 999 stone steps. 429 00:22:20,131 --> 00:22:23,617 Narrator: Stepping all over the park 430 00:22:23,618 --> 00:22:25,458 is exactly what thousands of people used to do. 431 00:22:25,516 --> 00:22:29,485 In the 1990s, 432 00:22:29,486 --> 00:22:31,279 word about the stunning landscape spread, 433 00:22:31,280 --> 00:22:32,920 and soon, huge numbers of curious tourists 434 00:22:34,042 --> 00:22:36,424 were tramping through the delicate forests 435 00:22:37,286 --> 00:22:40,150 and climbing its fragile rocks. 436 00:22:40,151 --> 00:22:43,153 Its ecosystem was suffering. 437 00:22:43,154 --> 00:22:44,846 The Chinese government had to act. 438 00:22:46,261 --> 00:22:49,401 One of the best views of the park is from this peak. 439 00:22:49,402 --> 00:22:51,922 So to keep visitors under control 440 00:22:53,337 --> 00:22:55,417 but still let them see the incredible natural wonder, 441 00:22:55,926 --> 00:22:58,722 they built this astonishing elevator, 442 00:22:59,999 --> 00:23:02,173 half inside, half outside a huge rock face. 443 00:23:07,420 --> 00:23:11,768 The visible 550 feet 444 00:23:11,769 --> 00:23:14,129 is actually only just over half the elevator's total height. 445 00:23:15,773 --> 00:23:18,604 The lower 500 feet 446 00:23:19,950 --> 00:23:21,790 is hidden in shafts tunnelled inside the cliff. 447 00:23:22,159 --> 00:23:24,279 And at the bottom of those is a 650-foot access tunnel 448 00:23:26,991 --> 00:23:29,925 leading to the main concourse. 449 00:23:30,754 --> 00:23:32,549 It all works smoothly now, 450 00:23:33,481 --> 00:23:34,761 but its creation was an epic feat 451 00:23:35,759 --> 00:23:37,208 of human endeavour and engineering. 452 00:23:41,178 --> 00:23:43,018 The first stage was to tunnel into the mountain 453 00:23:43,042 --> 00:23:45,631 to where they were going to build 454 00:23:46,494 --> 00:23:48,460 the base of the lift shafts. 455 00:23:48,461 --> 00:23:50,981 Today, it's used by hordes of visitors 456 00:23:51,740 --> 00:23:54,467 to reach the elevators 457 00:23:55,572 --> 00:23:57,296 after they've gotten off their coaches. 458 00:23:57,297 --> 00:23:59,541 But when the project was started in 1999, 459 00:24:00,611 --> 00:24:02,924 road access was severely limited 460 00:24:04,166 --> 00:24:05,846 and no heavy equipment could be brought in. 461 00:24:06,997 --> 00:24:09,620 Liu jie is manager of the elevator facility. 462 00:24:11,726 --> 00:24:14,522 [Speaking Chinese] 463 00:24:15,833 --> 00:24:17,732 Liu jie, translated: We used 100% human labor, 464 00:24:18,940 --> 00:24:20,780 with no heavy equipment and industrial machines 465 00:24:21,460 --> 00:24:23,565 used during construction. 466 00:24:24,773 --> 00:24:27,326 Workers carried all the equipment and materials 467 00:24:27,327 --> 00:24:29,950 on their shoulders or with their hands 468 00:24:29,951 --> 00:24:31,987 to the hillside. 469 00:24:35,025 --> 00:24:36,715 Narrator: So using only hand tools, 470 00:24:36,716 --> 00:24:38,856 the tunnellers got to work. 471 00:24:39,961 --> 00:24:42,101 Jie, translated: We first dug a tunnel 472 00:24:42,998 --> 00:24:45,206 into the mountain at its foot. 473 00:24:45,207 --> 00:24:47,007 Then we drilled the elevator shaft in reverse, 474 00:24:48,487 --> 00:24:51,282 from bottom to top. 475 00:24:54,907 --> 00:24:56,424 Narrator: Yes, you heard correctly. 476 00:24:56,425 --> 00:24:58,669 They drilled the shaft upwards. 477 00:24:59,946 --> 00:25:01,666 This is called reverse circulation drilling. 478 00:25:05,504 --> 00:25:07,464 Jie, translated: Drilling Wells from bottom to top 479 00:25:08,161 --> 00:25:10,577 is actually very difficult and dangerous, 480 00:25:10,578 --> 00:25:12,778 as the Wells above the workers can collapse at any time, 481 00:25:13,408 --> 00:25:16,204 and yet workers had to keep drilling upward. 482 00:25:17,481 --> 00:25:19,587 Narrator: With the 500-foot shaft reinforced, 483 00:25:20,484 --> 00:25:22,797 the exposed mountainside above 484 00:25:24,108 --> 00:25:26,178 needed to be made much more stable and strong 485 00:25:26,179 --> 00:25:28,181 before it could take the weight of the elevators. 486 00:25:32,392 --> 00:25:36,568 Jie, translated: More than 4,000 rock bolts 487 00:25:36,569 --> 00:25:38,609 were inserted up all 326 meters of the mountainside, 488 00:25:39,089 --> 00:25:41,816 and anchor cables were connected to the rock bolts 489 00:25:42,955 --> 00:25:44,715 so they could surround the mountain. 490 00:25:46,027 --> 00:25:47,787 Narrator: With the 500-foot shaft reinforced, 491 00:25:48,685 --> 00:25:50,825 the exposed mountainside above 492 00:25:52,136 --> 00:25:54,137 needed to be made much more stable and strong 493 00:25:54,138 --> 00:25:56,106 before it could take the weight of the elevators. 494 00:26:00,317 --> 00:26:02,284 Next, the huge steel derricks, or frames, 495 00:26:03,458 --> 00:26:06,185 were bolted on the reinforced cliff face. 496 00:26:08,187 --> 00:26:10,879 Finally, the elevator cabs would be installed. 497 00:26:13,123 --> 00:26:15,884 Those three huge double-Decker cabs 498 00:26:17,058 --> 00:26:18,698 can each carry a payload of almost 5 tons, 499 00:26:19,681 --> 00:26:23,822 or over 50 people. 500 00:26:23,823 --> 00:26:25,703 With their high speed of over 16 feet per second 501 00:26:26,067 --> 00:26:28,621 and world-record 1,070-foot climb height, 502 00:26:29,829 --> 00:26:32,591 they demand state-of-the-art control systems. 503 00:26:34,075 --> 00:26:36,836 Computers kept the cabs balanced and smooth in transit. 504 00:26:38,631 --> 00:26:42,565 To save power, 505 00:26:42,566 --> 00:26:43,532 electrical energy is recovered by the motors 506 00:26:43,533 --> 00:26:45,742 as the cabs descend. 507 00:26:47,157 --> 00:26:49,237 But perhaps the most important engineering at bailong 508 00:26:49,746 --> 00:26:53,956 are its safety systems, 509 00:26:53,957 --> 00:26:56,037 because the stunning beauty of the zhangjiajie region 510 00:26:56,062 --> 00:26:58,858 hides a deadly threat. 511 00:26:59,790 --> 00:27:02,690 Joshua: It is an earthquake zone 512 00:27:04,243 --> 00:27:05,381 where they've had historically quite significant earthquakes 513 00:27:05,382 --> 00:27:07,833 that have killed a large number of people 514 00:27:08,903 --> 00:27:10,869 in the vicinity and in the surroundings, 515 00:27:10,870 --> 00:27:12,664 and it's something that could happen again. 516 00:27:12,665 --> 00:27:14,705 Narrator: With the elevators in almost constant use, 517 00:27:15,634 --> 00:27:17,714 raising over 20,000 people up to the viewing platform 518 00:27:18,567 --> 00:27:22,260 every day of the week, 519 00:27:22,261 --> 00:27:23,813 the consequences of a major quake 520 00:27:23,814 --> 00:27:26,091 could be catastrophic. 521 00:27:26,092 --> 00:27:29,647 So bailong's engineers 522 00:27:29,648 --> 00:27:30,924 have built in every safety feature they could 523 00:27:30,925 --> 00:27:33,444 to quake-proof the structure. 524 00:27:38,415 --> 00:27:41,280 Jie, translated: We have seven wire ropes 525 00:27:41,901 --> 00:27:43,731 above the cab, 526 00:27:44,835 --> 00:27:45,802 and actually, every single one of them 527 00:27:45,803 --> 00:27:47,044 can hold the weight of the cab. 528 00:27:49,875 --> 00:27:51,359 The second safety measure 529 00:27:52,705 --> 00:27:54,464 are the guide rails along both sides of the cab. 530 00:27:54,465 --> 00:27:57,054 The cab is tightly fitted to these rails 531 00:27:58,538 --> 00:28:00,738 and has brakes which will stop the elevator from falling 532 00:28:02,266 --> 00:28:05,235 even if all seven cables fail. 533 00:28:08,687 --> 00:28:12,482 The third safety guard 534 00:28:12,483 --> 00:28:13,843 are the four hydraulic bumper posts 535 00:28:14,900 --> 00:28:17,039 we installed in the elevator pit. 536 00:28:17,040 --> 00:28:18,560 This is to soften the impact of the cab 537 00:28:19,249 --> 00:28:20,769 if the other safety gear fails to work. 538 00:28:24,737 --> 00:28:26,737 Narrator: Of course, prior warning of an earthquake 539 00:28:27,498 --> 00:28:29,466 would be the best safety feature of them all. 540 00:28:31,226 --> 00:28:34,057 Just a few seconds' warning 541 00:28:35,161 --> 00:28:37,231 could save hundreds of lives here. 542 00:28:37,232 --> 00:28:39,352 So a system of lasers is sighted on distant hillsides, 543 00:28:40,891 --> 00:28:44,756 which train back to receptors 544 00:28:44,757 --> 00:28:47,069 mounted onto the steel structure. 545 00:28:47,070 --> 00:28:49,762 Hayley: The lasers shining across the mountain 546 00:28:50,487 --> 00:28:51,868 are extremely sensitive. 547 00:28:53,317 --> 00:28:54,950 They can monitor the tiniest of movements in the earth 548 00:28:54,974 --> 00:28:58,494 and can notify the control room 549 00:28:58,495 --> 00:29:00,427 to perform evacuation procedures. 550 00:29:00,428 --> 00:29:02,361 Narrator: Just a few millimetres of movement 551 00:29:03,086 --> 00:29:04,984 will trigger the alarm, 552 00:29:05,605 --> 00:29:07,779 and instantly, 553 00:29:07,780 --> 00:29:08,918 the elevators will automatically take passengers 554 00:29:08,919 --> 00:29:10,852 to one of the evacuation exits, 555 00:29:12,060 --> 00:29:13,620 built every 36 feet into the cliff face. 556 00:29:18,204 --> 00:29:20,067 For now, the earth moves only for those lucky enough 557 00:29:20,068 --> 00:29:22,381 to gaze at one of the planet's great natural wonders. 558 00:29:27,766 --> 00:29:31,699 Jie, translated: Since 2015, 559 00:29:31,700 --> 00:29:33,287 we have experienced an explosive increase 560 00:29:33,288 --> 00:29:34,876 in the number of visitors, 561 00:29:36,291 --> 00:29:38,331 with about 4.5 million tourists coming here in 2018. 562 00:29:40,054 --> 00:29:42,884 Narrator: The park is now 563 00:29:44,230 --> 00:29:45,541 the second most popular tourist attraction in China, 564 00:29:45,542 --> 00:29:47,993 and it's being kept in pristine condition, 565 00:29:48,856 --> 00:29:50,996 all thanks to the engineers 566 00:29:52,445 --> 00:29:54,565 who figured out how to build this incredible elevator. 567 00:30:03,698 --> 00:30:07,183 Paris, France. 568 00:30:07,184 --> 00:30:09,185 Carefully planned. 569 00:30:09,186 --> 00:30:11,878 Very traditional. 570 00:30:11,879 --> 00:30:13,466 Famous for its immaculate boulevards 571 00:30:14,329 --> 00:30:17,745 and ornate apartment buildings, 572 00:30:17,746 --> 00:30:19,506 all combining to create its unique character. 573 00:30:20,611 --> 00:30:22,959 No wonder, when bold new structures are proposed, 574 00:30:24,512 --> 00:30:26,963 it often takes a while before the parisians appreciate them. 575 00:30:28,723 --> 00:30:31,519 In 1889, the Eiffel Tower was described 576 00:30:32,382 --> 00:30:35,281 as "a truly tragic street lamp;" 577 00:30:36,627 --> 00:30:38,507 in 1977, the Pompidou centre simply "monstrous." 578 00:30:41,115 --> 00:30:43,876 And in 2006, a new building joined their ranks. 579 00:30:51,435 --> 00:30:54,197 Debbie: This building is definitely out there. 580 00:30:54,783 --> 00:30:57,131 It's weird. 581 00:30:57,994 --> 00:30:58,926 You look at it, and you're like, 582 00:30:58,926 --> 00:30:59,754 is it a broken perfume bottle? 583 00:30:59,755 --> 00:31:01,445 Is it a giant ship? 584 00:31:02,343 --> 00:31:04,068 Is it a ufo from outer space? 585 00:31:04,069 --> 00:31:06,865 Narrator: A building designed 586 00:31:08,107 --> 00:31:08,970 by one of the world's greatest architects 587 00:31:08,971 --> 00:31:11,179 that locals hated 588 00:31:11,904 --> 00:31:13,180 and set out to stop. 589 00:31:13,181 --> 00:31:17,115 Man: In Paris, 590 00:31:17,116 --> 00:31:19,048 it's difficult to imagine this kind of a building. 591 00:31:19,049 --> 00:31:22,603 Narrator: Bankrolled by a billionaire, 592 00:31:22,604 --> 00:31:23,882 money was not the problem. 593 00:31:24,952 --> 00:31:26,232 Figuring out how to build it was. 594 00:31:27,644 --> 00:31:30,004 Man: I think it's fair to say there were some very dark days 595 00:31:30,889 --> 00:31:32,809 in the process of putting this building together. 596 00:31:33,029 --> 00:31:35,307 Narrator: The challenge of creating 597 00:31:36,135 --> 00:31:38,792 this astonishing building 598 00:31:38,793 --> 00:31:40,495 took hundreds of engineers, architects, and craftspeople 599 00:31:40,519 --> 00:31:43,246 eight years and 800 million Euros 600 00:31:43,832 --> 00:31:46,525 to overcome. 601 00:31:47,250 --> 00:31:48,630 So, how did they do it? 602 00:31:51,323 --> 00:31:54,152 When a man worth $100 billion 603 00:31:54,153 --> 00:31:56,313 decides he wants a new building for his art collection, 604 00:31:56,949 --> 00:32:00,296 he doesn't just buy one at random. 605 00:32:00,297 --> 00:32:02,437 Instead, in 2006, 606 00:32:03,507 --> 00:32:04,992 luxury brand magnate Bernard arnault 607 00:32:06,096 --> 00:32:07,995 got in touch with the man described 608 00:32:09,341 --> 00:32:11,146 as perhaps the world's most important architect. 609 00:32:11,170 --> 00:32:14,001 94-year-old frank gehry 610 00:32:15,174 --> 00:32:16,614 dreamed up Bilbao's guggenheim museum 611 00:32:17,763 --> 00:32:19,763 and the extraordinary Lou ruvo centre in Las Vegas. 612 00:32:24,528 --> 00:32:27,220 This time, gehry was inspired 613 00:32:27,221 --> 00:32:29,021 by the great glass palaces of the 19th century 614 00:32:29,499 --> 00:32:32,226 and designed a building that would set a new benchmark 615 00:32:33,261 --> 00:32:35,746 in extreme engineering challenges. 616 00:32:39,854 --> 00:32:41,774 The 126,000-square-foot building was to be called 617 00:32:43,064 --> 00:32:46,722 the Louis Vuitton foundation museum. 618 00:32:46,723 --> 00:32:49,243 It would include a massive waterfall, 619 00:32:49,864 --> 00:32:52,486 11 galleries, 620 00:32:52,487 --> 00:32:54,523 and a 350-seat auditorium. 621 00:32:54,524 --> 00:32:57,078 It would have huge steel icebergs 622 00:32:58,424 --> 00:33:00,304 and all be shrouded in 12 billowing glass sails. 623 00:33:01,255 --> 00:33:04,051 The budget was a cool 130 million Euros. 624 00:33:06,363 --> 00:33:09,125 Frank gehry's buildings were already notorious 625 00:33:10,471 --> 00:33:12,438 for challenging engineers' abilities to innovate. 626 00:33:13,992 --> 00:33:16,312 This building would take that reputation to the next level. 627 00:33:19,135 --> 00:33:21,792 James cowey spent a decade of his life working it out. 628 00:33:25,451 --> 00:33:28,178 James cowey: This was not a smooth ride down the river, 629 00:33:28,730 --> 00:33:30,353 as we say. 630 00:33:31,561 --> 00:33:33,287 Myself and the engineers went to Los Angeles 631 00:33:34,150 --> 00:33:36,186 to meet with gehry partners 632 00:33:37,636 --> 00:33:38,808 as they proudly showed us their model of the building, 633 00:33:38,809 --> 00:33:40,156 what they intended to build. 634 00:33:41,398 --> 00:33:43,606 And they did a very, very long exposition, 635 00:33:43,607 --> 00:33:45,767 and they finished by saying, "well, what do you think?" 636 00:33:46,645 --> 00:33:48,933 And the structural engineer next to me thought for a second 637 00:33:48,957 --> 00:33:51,201 and then said, "I think you used a lot of glue 638 00:33:52,271 --> 00:33:54,170 to make your models stand together." 639 00:33:55,447 --> 00:33:57,127 Narrator: Gehry's "glue happy" model makers 640 00:33:57,656 --> 00:33:59,382 had good reason not to confront the question 641 00:34:00,107 --> 00:34:02,454 of how to build it. 642 00:34:03,351 --> 00:34:05,421 The design's sheer originality 643 00:34:05,422 --> 00:34:07,342 meant there was no structural template to follow, 644 00:34:07,528 --> 00:34:09,564 nothing to suggest it was actually possible. 645 00:34:11,221 --> 00:34:14,741 But cowey's team took a logical approach 646 00:34:14,742 --> 00:34:16,502 to planning the build. 647 00:34:17,814 --> 00:34:19,614 James: It's a very tricky and complex building 648 00:34:20,196 --> 00:34:21,680 geometrically, obviously, 649 00:34:22,715 --> 00:34:24,199 when you see it from the outside. 650 00:34:24,200 --> 00:34:25,821 You could break it down to four basic systems 651 00:34:25,822 --> 00:34:27,065 that put the building together. 652 00:34:29,653 --> 00:34:31,378 Narrator: The engineers devised a solution 653 00:34:31,379 --> 00:34:33,278 that was based on illusion. 654 00:34:36,419 --> 00:34:39,145 The huge glass sails appear to be supported 655 00:34:39,146 --> 00:34:41,266 by the small curving structures known as the icebergs. 656 00:34:42,873 --> 00:34:45,704 A signature of frank gehry designs, 657 00:34:46,774 --> 00:34:48,334 they look like the core of the building, 658 00:34:48,879 --> 00:34:51,709 but they're not. 659 00:34:51,710 --> 00:34:54,125 Melt away the icebergs, 660 00:34:54,126 --> 00:34:55,885 and some very conventional concrete cubes emerge, 661 00:34:55,886 --> 00:34:58,544 within which are the gallery spaces themselves. 662 00:34:59,683 --> 00:35:02,686 Now, these are not very gehry, 663 00:35:03,411 --> 00:35:06,275 but they are very solid 664 00:35:06,276 --> 00:35:07,759 and allow the building's outer skin of sails 665 00:35:07,760 --> 00:35:09,797 to be so extreme. 666 00:35:12,834 --> 00:35:14,284 Nehemiah: They give the appearance 667 00:35:15,630 --> 00:35:16,493 as if the sails are floating in the air unsupported, 668 00:35:16,494 --> 00:35:20,462 but obviously we know 669 00:35:20,463 --> 00:35:21,946 that levitation of buildings hasn't been invented yet. 670 00:35:21,947 --> 00:35:24,225 Narrator: To give the appearance of levitation, 671 00:35:24,984 --> 00:35:26,814 the flimsy glass sails 672 00:35:27,884 --> 00:35:30,023 would need many more smaller fixings 673 00:35:30,024 --> 00:35:32,504 because, of course, being sails, strong wind was a big concern. 674 00:35:34,580 --> 00:35:37,307 The forces of gravity and wind on a building 675 00:35:38,653 --> 00:35:40,533 would normally be calculated by computer models. 676 00:35:41,967 --> 00:35:44,327 But so much was unknown about these ultra-complex structures 677 00:35:45,315 --> 00:35:49,491 that computer modelling wasn't trusted. 678 00:35:49,492 --> 00:35:51,612 Getting the plan right meant going back to the basics. 679 00:35:56,015 --> 00:35:58,500 James: We built a mini building, 680 00:35:58,501 --> 00:35:59,501 which was not more than 50 square meters on the ground. 681 00:35:59,502 --> 00:36:01,435 We have all of the systems... 682 00:36:02,677 --> 00:36:03,850 The sails, the glass enclosure, the icebergs. 683 00:36:03,851 --> 00:36:06,647 And we did a test run 684 00:36:07,889 --> 00:36:08,924 in which we evacuated many of the problems 685 00:36:08,925 --> 00:36:10,445 that we would have been confronted with 686 00:36:11,479 --> 00:36:12,721 if we had built without doing this test. 687 00:36:12,722 --> 00:36:14,551 Narrator: The successful dry run 688 00:36:15,759 --> 00:36:17,243 of the Louis Vuitton foundation museum in Paris 689 00:36:17,244 --> 00:36:21,419 gave the builders the green light. 690 00:36:21,420 --> 00:36:23,740 By 2011, the project had been underway for over five years. 691 00:36:24,803 --> 00:36:27,530 But as the foundations and central concrete structures 692 00:36:28,324 --> 00:36:32,223 began to appear, 693 00:36:32,224 --> 00:36:33,535 protests about the size of the building 694 00:36:33,536 --> 00:36:36,434 and its impact on the park intensified. 695 00:36:36,435 --> 00:36:38,437 Nehemiah: A group of Paris residents challenged it. 696 00:36:39,162 --> 00:36:40,750 They didn't like it. 697 00:36:42,096 --> 00:36:42,855 They challenged the original construction permit. 698 00:36:42,856 --> 00:36:44,685 Narrator: A court order 699 00:36:46,065 --> 00:36:47,411 found the building contravened parisian planning laws. 700 00:36:47,412 --> 00:36:49,759 The huge project was stopped in its tracks. 701 00:36:51,070 --> 00:36:53,452 James: When we were asked to suspend construction, 702 00:36:54,557 --> 00:36:56,037 we were quite in the middle of things. 703 00:36:57,284 --> 00:36:58,974 And so we had to keep working for another two or three months 704 00:36:58,975 --> 00:37:01,215 just to stabilize the building so work could be suspended 705 00:37:01,667 --> 00:37:03,531 because it was in a bit of a precarious state. 706 00:37:04,877 --> 00:37:06,786 Narrator: With one-third of all the scaffolding in France 707 00:37:06,810 --> 00:37:09,330 on site, 708 00:37:09,917 --> 00:37:11,918 gehry, arnault, 709 00:37:11,919 --> 00:37:13,747 and the hundreds of specialists involved 710 00:37:13,748 --> 00:37:15,508 found their dream in the hands of the courts. 711 00:37:19,133 --> 00:37:21,894 But Bernard arnault fought back. 712 00:37:22,964 --> 00:37:24,863 The court battle ended four months later, 713 00:37:26,347 --> 00:37:28,827 when the city of Paris suddenly changed its laws on land usage. 714 00:37:29,281 --> 00:37:33,146 Frank gehry was back in business. 715 00:37:33,147 --> 00:37:35,873 While the foundations and concrete cubes 716 00:37:35,874 --> 00:37:37,565 were taking shape, 717 00:37:38,635 --> 00:37:39,980 the components that would create 718 00:37:39,981 --> 00:37:42,120 the steel icebergs and glass sails 719 00:37:42,121 --> 00:37:44,001 were being made off site, a long way from Paris. 720 00:37:45,090 --> 00:37:47,782 Gehry's mixed use of material was typical and challenging. 721 00:37:50,164 --> 00:37:52,994 Arcing beams of wood and steel 722 00:37:54,168 --> 00:37:55,728 support impossibly complex glass panels, 723 00:37:56,377 --> 00:38:00,242 many exposed to the elements. 724 00:38:00,243 --> 00:38:02,970 Making these to the highest standards 725 00:38:04,489 --> 00:38:06,770 meant using only the very best workshops and craftspeople. 726 00:38:10,426 --> 00:38:12,876 Engineer Bernard vaudeville 727 00:38:14,257 --> 00:38:16,028 helped coordinate the massive Europe-wide project. 728 00:38:16,052 --> 00:38:18,986 Bernard vaudeville: All the elements 729 00:38:19,676 --> 00:38:20,814 are prefabricated, 730 00:38:20,815 --> 00:38:22,575 they are made in workshops 731 00:38:22,576 --> 00:38:23,679 which are 100 kilometres away from Paris. 732 00:38:23,680 --> 00:38:25,372 For the glass, it's made in Italy, 733 00:38:26,442 --> 00:38:27,722 and the wood was made in Germany, 734 00:38:28,927 --> 00:38:30,928 and some other elements were made in Belgium, 735 00:38:30,929 --> 00:38:33,862 so all these elements had to come from far away 736 00:38:33,863 --> 00:38:37,521 and they were all prefabricated. 737 00:38:37,522 --> 00:38:39,868 Narrator: More than 400 specialist fabricators 738 00:38:39,869 --> 00:38:42,009 in four different countries 739 00:38:43,079 --> 00:38:45,563 would create the 23,000 unique pieces 740 00:38:45,564 --> 00:38:49,015 that must somehow all fit together perfectly 741 00:38:49,016 --> 00:38:51,812 when assembled on site. 742 00:38:53,158 --> 00:38:55,198 Ellie: That's basically the Jigsaw puzzle from hell. 743 00:38:58,163 --> 00:38:58,888 Narrator: So how did they make sure 744 00:38:58,889 --> 00:39:01,303 it would all slot together? 745 00:39:01,304 --> 00:39:03,489 The designers used a system created for a very different 746 00:39:03,513 --> 00:39:07,482 but even more demanding industry. 747 00:39:07,483 --> 00:39:10,037 Hayley: The designers used a technology 748 00:39:11,141 --> 00:39:12,625 pioneered by the aviation industry. 749 00:39:12,626 --> 00:39:15,007 It's called b.I.M., 750 00:39:15,870 --> 00:39:18,355 building information model. 751 00:39:18,356 --> 00:39:20,836 It lets all of the manufacturers add information to a 3-d model 752 00:39:21,807 --> 00:39:24,500 and then lets the designers check what everyone is doing. 753 00:39:29,574 --> 00:39:31,294 Narrator: This shared virtual building model 754 00:39:31,507 --> 00:39:34,267 meant teams on site and off site 755 00:39:34,268 --> 00:39:37,097 were all fully aware of any problems arising, 756 00:39:37,098 --> 00:39:40,032 and could rapidly plan solutions, 757 00:39:41,379 --> 00:39:43,539 dodging time-consuming meetings and expensive mistakes. 758 00:39:45,141 --> 00:39:48,937 James: Basically this model was the base 759 00:39:48,938 --> 00:39:51,180 on which everything was created. 760 00:39:51,181 --> 00:39:52,769 And it allowed for the contractors 761 00:39:54,115 --> 00:39:55,461 in different parts of the world to fabricate pieces 762 00:39:55,462 --> 00:39:58,395 of amazing geometrical complexity. 763 00:39:58,396 --> 00:40:00,743 Narrator: First of the prefabricated structures 764 00:40:01,468 --> 00:40:04,021 to be assembled on site 765 00:40:04,022 --> 00:40:06,126 were the icebergs. 766 00:40:06,127 --> 00:40:07,680 Cedric joie: We're here in the iceberg, 767 00:40:07,681 --> 00:40:09,545 the highest one. 768 00:40:10,718 --> 00:40:11,891 These shells were prefabricated in Belgium 769 00:40:11,892 --> 00:40:13,963 and were transported to the site, to Paris, 770 00:40:14,688 --> 00:40:16,586 on trucks, trailers, 771 00:40:17,829 --> 00:40:19,726 and assembled, as you can see, with bolts, 772 00:40:19,727 --> 00:40:23,489 simply bolts, 773 00:40:23,490 --> 00:40:24,974 with joints that you can see here. 774 00:40:26,044 --> 00:40:27,494 All of these shells were different. 775 00:40:28,356 --> 00:40:30,082 There were 365 different shells 776 00:40:31,152 --> 00:40:33,569 for all the icebergs of the project. 777 00:40:34,293 --> 00:40:35,881 It was assembled on site 778 00:40:37,124 --> 00:40:38,884 to compose the external shell of the iceberg. 779 00:40:43,337 --> 00:40:44,786 Narrator: Now the iceberg shells needed to be clad 780 00:40:44,787 --> 00:40:47,099 with a huge number of custom-made white tiles, 781 00:40:48,307 --> 00:40:50,620 which all had to be just the right size 782 00:40:51,345 --> 00:40:53,692 before they arrived. 783 00:40:54,728 --> 00:40:56,729 Corina: Normally it doesn't matter 784 00:40:56,730 --> 00:40:58,351 if you have to adjust things on site. 785 00:40:58,352 --> 00:41:00,284 I mean, that's part of the building process. 786 00:41:00,285 --> 00:41:02,366 But you can't really do that if everything is so custom-made. 787 00:41:02,390 --> 00:41:06,393 Narrator: Instead, 788 00:41:06,394 --> 00:41:07,809 Bernard's team relied on components being made 789 00:41:07,810 --> 00:41:10,674 to within a few millimetres of specification 790 00:41:10,675 --> 00:41:13,746 so they weren't too close or too far apart, 791 00:41:13,747 --> 00:41:16,715 once assembled. 792 00:41:18,027 --> 00:41:19,993 Bernard: Assembling them on site is very difficult 793 00:41:19,994 --> 00:41:22,687 because there is something we call tolerances. 794 00:41:24,102 --> 00:41:26,102 Tolerances means that when you fabricate something, 795 00:41:26,898 --> 00:41:29,797 it's never exact, never. 796 00:41:31,074 --> 00:41:32,834 You can't do that. Exactitude is only divine. 797 00:41:33,870 --> 00:41:36,804 It doesn't exist. 798 00:41:37,978 --> 00:41:39,668 Narrator: Because every tile is different, 799 00:41:39,669 --> 00:41:41,909 each one had to be attached in precisely the right order. 800 00:41:42,948 --> 00:41:45,710 Cedric: You have 19,000 of these white panels. 801 00:41:47,021 --> 00:41:49,921 Almost all are different. 802 00:41:50,784 --> 00:41:53,924 Bernard: So they came in boxes. 803 00:41:53,925 --> 00:41:56,340 When you opened the box, 804 00:41:56,341 --> 00:41:57,479 the panels had to be in the right order. 805 00:41:57,480 --> 00:41:59,827 You can't open 50 boxes 806 00:42:00,897 --> 00:42:02,497 in order to find where the good panel is. 807 00:42:04,487 --> 00:42:07,248 Narrator: The icebergs complete, 808 00:42:08,042 --> 00:42:10,457 next came the huge sails. 809 00:42:10,458 --> 00:42:12,378 With nearly 140,000 square feet of curving glass, 810 00:42:13,600 --> 00:42:16,326 these were perhaps the most challenging features of all 811 00:42:17,258 --> 00:42:20,054 to create. 812 00:42:20,952 --> 00:42:22,435 James: 3,500 panels of glass, 813 00:42:22,436 --> 00:42:24,195 with each one with an individual design 814 00:42:24,196 --> 00:42:25,956 for which special ovens had to be created 815 00:42:25,957 --> 00:42:28,131 to manage the curve, 816 00:42:29,443 --> 00:42:30,375 to manage the way the surface would be treated 817 00:42:30,376 --> 00:42:31,825 to reflect or not reflect light. 818 00:42:32,998 --> 00:42:34,638 Narrator: Commercial car windshield-making 819 00:42:35,414 --> 00:42:37,830 combined with meticulous hand craftsmanship 820 00:42:37,831 --> 00:42:39,831 to ensure each panel curved precisely the right way 821 00:42:40,972 --> 00:42:43,837 and was safe to install. 822 00:42:45,183 --> 00:42:47,063 James: There were multiple, multiple constraints 823 00:42:47,565 --> 00:42:50,049 just on the glass 824 00:42:50,050 --> 00:42:51,498 that required us to work with glass manufacturers 825 00:42:51,499 --> 00:42:53,339 to invent a whole new way of fabricating glass. 826 00:42:57,713 --> 00:43:01,370 Narrator: Finally, in 2014, 827 00:43:01,371 --> 00:43:03,270 eight years after it began 828 00:43:04,340 --> 00:43:05,900 and with nearly 800 million Euros spent, 829 00:43:07,308 --> 00:43:10,035 the Louis Vuitton foundation museum 830 00:43:11,243 --> 00:43:13,245 was ready to hold its first exhibition. 831 00:43:14,522 --> 00:43:16,870 But for many, the art inside was a sideshow, 832 00:43:18,009 --> 00:43:20,874 because frank gehry, 833 00:43:22,047 --> 00:43:23,358 his architects, engineers, and craftspeople 834 00:43:23,359 --> 00:43:26,155 had achieved something extraordinary. 835 00:43:30,642 --> 00:43:33,437 Joshua: The thing I really love about this building 836 00:43:33,438 --> 00:43:35,508 is that the structure is on display. 837 00:43:35,509 --> 00:43:37,475 So many buildings, the structure, the actual bits 838 00:43:37,476 --> 00:43:40,064 that hold up the weight and the floors, 839 00:43:40,065 --> 00:43:41,757 it's just not visible. 840 00:43:42,965 --> 00:43:43,793 It's behind walls, it's behind cladding, 841 00:43:43,794 --> 00:43:45,000 you never see it. 842 00:43:45,001 --> 00:43:46,657 But with this structure, 843 00:43:46,658 --> 00:43:48,038 @you can really see the columns, the frame, the skin. 844 00:43:48,039 --> 00:43:49,765 And to me, that's really inspiring. 845 00:43:50,455 --> 00:43:53,285 Corina: Beautiful. 846 00:43:54,632 --> 00:43:55,908 But the work that went into it was extraordinary. 847 00:43:55,909 --> 00:43:58,704 Narrator: Against what seemed impossible odds, 848 00:43:58,705 --> 00:44:00,672 Paris had a new icon on its skyline 849 00:44:02,053 --> 00:44:03,973 to match perhaps even that famous tower of steel.