Biltmore and Building Specialization
Plus: structural framing cost curves, a case for brick and mortar, modular Chick Filas, and closing bank branches.
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I recently visited Biltmore, a mansion outside of Asheville that’s the largest privately owned house in the US. Biltmore is an interesting house for a lot of reasons, but one is that it was designed like a 16th century european country estate, but was built in the 1890s, when a lot of what we’d consider “modern” building technology was in place, and which Biltmore included - electricity, hot and cold running water, mechanical refrigeration, central heating, etc. But because it was built in the late 1800s and isolated from any major urban area, Biltmore couldn’t just hook up to an electrical grid or a sewer line. Like the country estates it was modeled after, it’s amenities and services mostly had to be provided by the house itself. This leads to some interesting mechanical systems (from Biltmore Estate: The Most Distinguished Private Place):
…Creating a hospitable environment in this vast and complex space meant providing heat, light, water, and electricity to 255 rooms, 43 bathrooms, 288 lighting fixtures, and 180 outlets...To produce the power needed...a gasoline engine was placed in the engine room in the cellar...The heart of the powertrain, the gasoline engine drove a generator that was connected to storage batteries and transformers and was thus capable of transmitting direct or alternating current. Belts linked the gasoline engine and electric motors driven by the generator to a system of overhead shafting which transmitted power to laundry equipment.
…The electrical current produced by the gasoline engine and the generator...was sent first to a switchboard...Mounted on the central panel were switches for the direct current to the electric motors, including those for the elevators, the ventilators, and the pump for the refrigerators; here also were switches for the forty-nine light circuits and metering devices to monitor the source and flow of current. If the generator was not running, knife switches permitted circuits on the central panel to be powered by storage batteries....The house features an electric dumbwaiter and two electric elevators
…Hunt’s specifications called for five mechanically operated refrigerators. There was a walk-in general storage cooler and separate refrigerators for the pastry room, the kitchen, the servants’ room, and the pantry...The refrigerators operated by using distilled ammonia to chill a brine solution. This chilled brine was circulated in pipes that passed through the well-insulated refrigerator cases.
…Establishing a water supply for the estate and the village was a topic of grave concern to both Hunt and Olmsted. A dam and streams on nearby Busbee Mountain, 266 higher than the proposed esplanade, was a promising source...mcNamee had difficulty obtaining a suitable right-of-way for the pipes, but on July 17, 1890, Thompson proudly informed Olmsted that “water was turned on to the Esplanade yesterday and now the mules are enjoying all they want.
…Hot water was instantaneously available at faucets throughout the house. Two coal-fired boilers in the basement heated water to a temperature of two hundred degrees Fahrenheit; it was then piped in a continuous loop throughout the house...The hot-air central heating system was also located in the basement. It’s three coal or wood-fired boilers, like those of a steam locomotive, contained pipes in which steam was produced. The steam from the boilers was piped through radiators located in kiln-like brick champers; the radiators heated air within the chambers, and the heated air was then drawn upstairs through a maze-like system of flues.
…Well before work got underway on the house, McNamee had installed a temporary telephone system having six “stations” and six miles of wire. The system was expanded in 1896...These interior lines were supplemented by a bell system like those used in contemporary hotels.
…Perhaps the most influential and symbolic use of technology was the system of synchronized clocks that made precise coordination possible. In the stable courtyard…is the “master clock”, guaranteed accurate within one minute per month, designed to be unaffected by wind, snow, or even birds roosting on its hands. Its custom-made movement is gravity-driven. Once each minute its escapement wheel activates a cam which opens and closes an electrical connection, and this current drives the “slave” clocks in the house.
Beyond the complex mechanical systems, running the house took huge amounts of labor. The house is 175,000 square feet spread across 4 floors and 2 basements, and roughly half of it consists of areas used exclusively by servants (including an entire floor of servants quarters). The basements are a huge warren of storerooms, boilers, pantries, kitchens, and laundry facilities required to keep the house running and the guests comfortable. In the late 1800s “modern” conveniences required huge rooms full of specialized equipment staffed with an army of servants to produce. In some ways Biltmore feels more like a ship than a house
The same is true of older country houses Biltmore emulated, which had rooms devoted to making alcohol and cosmetics, cooking pastries, making sauces, or smoking meats. And to a lesser extent it was true of even “normal” houses - the 19th century American homestead, far from being a simple residence, was an important center of production. From there families would engage in sewing clothing, making cheese, storing cut firewood, pickling meat, drying fruit, or making soap.
If you go back further, you see the same thing even in urban areas. Medieval cities often consisted of masses of undifferentiated buildings known as “burgher houses” which simultaneously served as retail space, office, workshop, home, and boarding house. From “Cities and Buildings”:
The urban house as we know it today - a dwelling separated from the workaday world and sheltering, at least ideally, one nuclear family - evolved in England. It’s predecessor, the medieval burgher house, had existed for centuries before and to a very real degree had been the basic component of the cityscape. Only with increasing architectural specialization and the separation of economic activities into purpose-built structures did the “house” begin to take shape. The medieval burger house in central and northern Europe was not a house in the modern sense of the word. Rather, it was an all-purpose mixed-use building that served as an important economic unit of production and distribution in the late medieval city. The merchant owner and his family occupied only a small portion of the total space - usually the second floor - and had very few personal belongings and furnishings. While the third and perhaps fourth floors housed apprentices and journeymen, the cellar was used for storage of goods and the first floor for sales. In some cases, upper floors were used for productive activities such as weaving. Such “houses'' were typically four to six stories tall and occupied small lots with narrow street frontages. They were built to last and were often used by the same family for decades, if not centuries.
Architectural specialization, like labor specialization, is something that happens gradually as economies grow, simultaneously a result and a cause of greater efficiency and economies of scale. Clerical work and business meetings, once done in merchants' houses or coffee shops, become extensive enough that specific buildings are created for the purpose (buildings specifically built for office work didn’t start to appear until the 1700s). Retail moves from a counter at the front of an artisans workshop to a specifically designed storefront (which may be far from where the goods were produced). Instead of generating your own electricity or treating your own water, it gets produced in large, centralized facilities and sent out over the grid.
We’ve previously talked about one of the effects advancing technology has on buildings, that as functionality gets provided by increasingly smaller, less expensive, more portable devices, it no longer requires specialized buildings or rooms to provide. Cooking fireplaces become stoves, refrigerators start out as rooms but end up as appliances.
But now we see another effect - as technology reduces transportation, coordination, and logistics costs, it removes constraints on the physical location of that functionality. An electrical grid that can transmit power efficiently over long distances means electricity doesn’t have to be generated inside your house like Biltmore - you can generate it wherever it makes the most sense to do so.
This can have a few different effects on buildings. In some cases, it means functionality gets centralized in a small number of locations to take maximum advantage of specialization, economies of scale, and agglomeration effects. People don’t produce their own electricity (and homes aren’t built with the functionality to do so) because one large power plant is much more efficient than 100,000 small power plants.
We see this occurring in housing in the late 19th century - advancing technology meant housework was easier, but it also meant that many parts of “home production” could be done more efficiently elsewhere. From “The American Family Home 1800-1960”:
The rapid expansion of commerce and industry brought with it a host of technological innovations that simplified everyday life. Laundering, which had once taken as much as one-third of a housewives time, was made more manageable with the invention of gas hot-water heaters, indoor plumbing, and hand-cranked mechanical washing machines. Home baking, which often took one day a week, could be reduced or eliminated altogether by the purchase of bakery products from urban bakeries or from the national biscuit company. Even the production of shirts and dresses was vastly simplified by the invention of the sewing machine. By 1900, the increasing use of products made outside the home had dramatically altered the time and space needed to manage the contemporary household.
(of course, clothing production has now moved more or less completely outside the home into factories devoted to that purpose).
Technological development, combined with a reduction in the use of servants, caused average home size to shrink in the late 1800s, as housing styles moved from large, ornate Victorians to more modest bungalows. Cities like New York and San Francisco are the ultimate version of outsourcing functionality, where people have access to a huge number of specialized amenities but generally live in small spaces.
Functionality concentrated in a particular location tends to result in buildings designed for that particular use. Centralized power production isn’t done in whatever building happens to be available, it’s done in specially designed power plants. Most modern buildings are designed for a specific sort of use. But specialized buildings can have a hard time adapting to new uses. A few examples:
Malls aren’t general purpose buildings or even general purpose locations for retail - they’re designed around specific patterns of retail consumption, and can’t easily adapt when those patterns shift.
An office building can’t easily be repurposed for residential use (the mechanical, electrical, and plumbing systems need to be changed completely).
A parking garage is so optimized for its design requirements that it's almost impossible to use it for anything except car storage.
Multistory apartment buildings are built using lightweight framing spanning between closely spaced interior walls, making them difficult to change to even a different residential layout, much less office or industrial use.
One reason movie theaters have been particularly hard hit by Covid is that it’s difficult to repurpose the space for anything else due to the sloped floors.
Specialization means that a building is not only designed for its particular function, it’s also located for its particular function. Brick and mortar retail is gradually getting replaced by e-commerce, but an Amazon fulfillment center is not only a different sort of building than a retail storefront, it’s built in a different place.
But reduced transportation and coordination costs can also push against building specialization. Right now we’re seeing a shift from office work being done in specialized office buildings to being done remotely in whatever space is available - coffee shops, kitchen tables, or spare bedrooms. Zoom, slack, email, dropbox, and other software tools allow office work to take place without the need of a specialized building. School work may be on a similar trajectory.
Over time, the arc of technology pulls building specialization in different directions. For instance, consider food preparation. Historically, it was one of the main functions of the home, with a large amount of space and equipment devoted to it. As technology advanced and distribution costs fell, it could more easily be done outside the home.
But simultaneously with this, electrification and industrial mass production made kitchen appliances increasingly affordable - so we also see trends towards decentralization. In the late 1800s/early 1900s, a popular living arrangement were apartments or hotels with centralized kitchens, where the costs of food preparation could be spread over many tenants. As kitchen appliances became more affordable, this style of living fell out of favor - people apparently wanted the flexibility of being able to prepare their own food, and apartments without kitchens essentially no longer exist.
Today we’re seeing a push back in the other direction, with the rise of food delivery startups and “ghost kitchens” (restaurants that are delivery only, and might prepare their food in a warehouse which houses 20+ different restaurant kitchens). If distribution costs fall enough, we may see food production increasingly centralized in large scale kitchens (in buildings designed for that purpose), with home kitchen functionality becoming more of a specialty option for the affluent or the enthusiast (the way a home theater or woodshop would be) rather than a basic housing requirement.
Office work is another area we see these trends working in different directions. The technology that enables office work to take place without a specialized building is enabled by the construction of large, specially designed datacenters. The degree and type of building specialization is in some sense a function of which costs are being reduced. Specialization along one axis can mean the opposite along another.
 - You can see this in the description of buildings that have been around for a long time (storehouse, warehouse, customs house, coffeehouse) - everything is some type of house.
 - Another example of a place technology might cause a shift in centralization and specialization - the falling cost of solar panels and batteries means that generating your own electricity is increasingly an option.
 - Though office buildings, as they’re designed to house a variety of potential tenants, are in general more flexible than most building types.
 - The modern, appliance-based kitchen requires little in the way of specialized building. The Great British Bake-Off is able to assemble 12 near professional level kitchens in an outdoor tent.
In AISC Design Guide 7 - Industrial Building Design, there’s an interesting table that gives the relative efficiency of different bay sizes for roofs framed with open web joists bearing on steel beams:
In designing a framing layout, an engineer faces a tradeoff - as your bay size increases, it requires larger and heavier framing elements to span, but the number of discrete framing elements required decreases. The table above illustrates this tradeoff, showing the shape of the cost frontier and the low point where your number of members and your member size combined reach minimum cost.
These are the sorts of problems that structural optimization software is often designed to tackle, but it’s actually somewhat complicated. One reason is that construction elements aren’t continuous, but come in discrete sizes and quantities - so these cost functions will actually have little steps in them (making it a type of integer programming). In practice, size differences in steel members are small enough that cost curves are likely pretty smooth. But something like precast concrete will have a cost curve full of nasty cliffs, due to high fixed costs per piece and the cost increase you’ll get if piece weight tips you into needing a larger crane (which in turn will be a function of what your bay size is).
Bear Case for Brick and Mortar Retailers - Investor makes the case for brick and mortar sticking around. Retail may indeed continue to shift to e-commerce, but that may mean increasing use of “buy online and pick up in store”, which will benefit large chains that have substantial retail footprints and distribution networks. This seems like another trend Covid has accelerated, everyone’s now looking for an excuse to not go into the store.
Chick Fila Experiments with Modular Building Construction - Chick Fila experimenting with modular building construction to reduce site time. This actually seems like it supports the idea that modular is mostly used in cases where a faster-than-usual construction time is an extremely important consideration. In this case, it’s being used for existing restaurants that are being rebuilt to handle more customers (presumably minimizing downtime is important for existing locations that people expect to be there).
Bank Branches Closing (FT, $) - Another trend accelerated by Covid, banks are closing branches throughout Europe as their functionality gets replaced by phone apps and Zoom calls. Banks are another example of a specialized building that’s not easily repurposed (at least in the US) - securely storing and handling money requires a lot of specialized equipment that’s mostly built into the building itself.
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