Tag Archives: comfortable buildings

Corner Stores

Corner stores are the opportunistic colonisers of underused space for our benefit. They’re the friendly bacteria of cities. Cities don’t work because of enigmatic signifiers, junk space or parameters. They work because of corner stores.

There’s not much about corner stores we don’t already know, apart from possibly the fact they’re usually called that because they’re located on the corner plots or street ends of rows of terraced housing, often Victorian or Edwardian factory workers’ houses. Here’s one from the early 1900s. It doesn’t look like the UK.

CornerStoreEarly1900s-long goodbye

Even if they didn’t stock Salada Tea, corner stores were a common sight in Britain until the 1970s. Many closed with the advent of large supermarkets that combined the services of many small local stores into a single building with lower overheads, centralised purchasing and whatnot. But many survived by offering a wider variety of services or opening for longer hours. Immigrant families had a competitive advantage as they were more likely to work those longer hours. Many stores were absorbed into franchises such as SevenEleven and came to be known as convenience stores.

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Trivia. In the states of Western Australia and South Australia, a small convenience store is often known as a deli (a contraction of delicatessen). Elsewhere, deli retains more of its original meaning.

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But wherever you are, corner stores are there for you when you run out of milk or bread. They’re there for you when you discover you’ve no tea or coffee for the morning, or when there’s people coming over and you forgot to buy cigarettes, alcohol, crisps and nuts. Many London convenience stores have a wide selection of cigarettes, alcohol, crisps and nuts as if that’s all city dwellers exist on.

This only reinforces the myth that the countryside is where real food exists, as told in Elizabeth David’s lovely book French Country Cooking. That myth was responsible for people wanting Agas and country-kitchens like the one below.

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This is exactly the kind of kitchen Alain de Botton describes in his book, The Architecture of Happiness. I had to throw the book away when I came across the line  “what could be more pleasant than the early-morning sunlight striking the honey-coloured stone of your kitchen floor?” (I paraphrase, but if you want to find it, you won’t have to read too far.) All this sentence tells me is that

  • your kitchen is a separate room with a window so you probably don’t live in a studio apartment – you live in a house
  • the early-morning (i.e. low-angle) sunlight enters your kitchen and strikes the floor so you probably have a rather large garden outside your kitchen window (i.e. you are rich)
  • you definitely don’t live in an apartment – at least not in London – because your kitchen has a stone floor
  • you are rich (or at least aspirational) because that stone is “honey-coloured” and it’s probably Yorkstone
  • Alain deBotton is a tosser

Of course, we all know that real food doesn’t exist in the countryside. It exists in urban restaurants because now we all want restaurant kitchens – or at least stainless steel stuff raised off the floor. The kitchen in this next image also works the common belief that good food comes not only from restaurants but from Italy.

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It’s a winning combination of associations this next kitchen doesn’t have.

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I digressed – but not by much. While all that was happening, the larger UK supermarkets built large out-of-town stores disguised as generic country-style buildings and trained people to do a “weekly shop” from a store on an arterial road in the bountiful countryside.

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An increasingly large proportion of the population without cars but with a certain amount of disposable income remained unexploited and this, like smoke follows fire, led to “urban supermarkets” a.k.a. chain spinoff stores selling cigarettes, alcohol, nuts and crisps. You won’t find steak, onions, spinach or salmon in many, if any. I have a memory of going to this one on Fulham Road, London but to buy what, I don’t know. Cigarettes probably, truth be told.

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Stores like these are a new revenue earner for large supermarket chains. Chains without them have profit warnings. Stores like these are spreading from city to suburb, forcing existing corner stores to be even more adaptable and diversify their services to include public transport cards, lottery tickets, post-office services, prepaid cards or recharges for mobile or transport, etc. The battlefield is convenience.

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  • Because of their family ownership and management, corner stores open for longer and with fewer holidays. This is good for you.
  • Home deliveries are more personal, more immediate
  • You can get many things done at a decent corner store.
  • If you get on good terms with the management, they may even let you run up a bill you can settle monthly

To sum up, corner stores are good. They’re here in Dubai too, and – ma shah’allah – they’re on corners! The standard 40m x 40m tower has four corners. Meet Millennium Tower (2006, ATKINS. Burj Al Arab reprise as pseudo-truss – believe me, I know.)

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Whatever we may think of Millennium Tower, the FoodLand store on the ground floor MAKES IT BETTER! Note the tricycles for stable and free home delivery.

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In buildings such as Millennium Tower, the double ground floor height means it’s possible to get a mezzanine in there for added stock. Win-win for all.

You can see this is a functioning supermarket by what’s on the shelves. It provides local residents with not only the stuff they need, but the stuff they might need. Just up the road is Oasis Tower, the one behind the 19th Street sign.

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Oasis House is host to not one but two corner stores.

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Do a 180 and you’ll be looking at Liberty House.

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Back in the pre-CC day, its four-storey lobby was all just space and sofas and babbling water in rock-lined pools delineating rows of columns as skirting boards might. Not now.

These days, the lower 4.50 metres of that space is colonised by an ALMAYA supermarket. Technically, Almaya isn’t a corner store not because it’s not on a corner but because it’s part of a small chain.

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I include it anyway because it well shows what happens when need meets under-exploited space. Plus – because Liberty House and I have history.

This post has no point other than to say LET’S HEAR IT FOR CORNER STORES! YAY!! They’re not architecture, they’re not even buildings FU. P.S.). They’re just some space with some useful stuff in them. Living is more than architecture, more than just shelter.

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Architecture Misfit #12: Nader Khalili

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Nader Khalili (1936–2008)

Nader Khalili is a good example of an architecture misfit. He really only had one idea. Put whatever sandy stuff is available, into bags, clad it and bingo you have a structure. In 1984 NASA was suitably impressed.

In 1984, Lunar and Space habitation became an integral part of his work. He presented his “Magma Structures” design, based on Geltaftan System, and “Velcro-Adobe” system (later to become Superadobe) at the 1984 NASA symposium, “Lunar Bases and Space Activities of the 21st Century.” He was subsequently invited to Los Alamos National Laboratory as a visiting scientist. 

Later however, he devoted his energies to the problem of how to build shelters for people in the world who have no money and the earthbag building is what he came up with. You’ve probably read about them sometime in the past several years. It difficult to think of a better solution to emergency or ultra-low cost housing.

The principle is simple. 1) Put sand into long bags and use them to make curved walls that act as their own stabilisers.

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2) Make spaces for openings as you wish.

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3) The earthbag curves are laid in gradually decreasing radii to form domes.

4) The entire thing is finished according to your local stucco and culturo-personal preference.

The construction method is infinitely variable, durable, earthquake resistant, thermally impressive and, above all, dirt cheap. It requires little skilled knowledge or labour to build. The most expensive component is the bags and the barbed wire [ ! ] that is ingeniously used to increase friction between the bags.

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What’s not to like? In the world of glossy architecture, possibly all of the above despite the fact that the system can also be used to construct some conventionally appealing spaces and in some conventionally appealing shapes

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and that have some fairly complex spatial arrangements.

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No disrespect intended to Calearth,

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but the Californification of Khalili’s system for off-grid living should not be allowed to overshadow its fundamental humanitarian purpose of providing low-cost and/or emergency housing.

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So then, Nader Khalili

You created a system that enables anyone
with some earthbags and land, to build a dwelling
that is sturdy, durable and comfortable.
For services to architecture and humanity

misfits salutes you!

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POSTSCRIPT: Acoustic suppression is not normally considered a major indicator of building performance but, apparently, Khalili’s structures reduce external noise by 17dB. Today’s Guardian reported that Heathrow airport is to pay 21 local schools to build Khalili’s “superadobe” shelters.

Pupils of Hounslow Heath school play around the huts in the playground as another low jet flies in

How this works out to £85,000 per school suggests someone is paying through the nose. Never trust those London builders’ quotes!

Architecture Misfit #10: Colin Lucas

colin anderson lucas

Colin Anderson Lucas (1906–84)

was an English architect and pioneer of reinforced-concrete construction. He formed a company to build concrete structures in the style of International Modernism, including Noah’s House at Spade Oak Reach, Bourne End, Bucks. (1930), and Hop Field House, St Mary’s Platt, Wrotham, Kent (1933—with Amyas Connell and Basil Ward (1902–76).

house in kent In 1933 he joined Connell and Ward to form Connell, Ward, & Lucas, and brought his expertise to the creation of a whole series of International Modernist houses such as High and Over Estate, Amersham, Buckinghamshire. (1929),

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There’s more information and pics here. And here’s a short contemporary (1931) film about it, titled The House of a Dream.

There was also the Gunn House, The Ridgeway, Westbury-on-Trym, Bristol (1936),

Gunn House the Tarburn House, Temple Gardens, Moor Park, Herts. (1937–8), Walford House, 66 Frognal, Hampstead, London (1937)

frognal and Potcraft, Thomas House, Sutton, Surrey (1938) unparalleled elsewhere in the country. In short, until WWII he had quite a respectable career.

After the 1939–45 war he worked in the Architects’ Department of the London County Council, heading a team of young Modernists who designed, among much else, the Le Corbusier-inspired Alton Estate West at Roehampton, London (1951–78), where the slab-blocks are on a very small scale yet superficially modelled on Le Corbusier’s Unités d’Habitation.

History tells us nothing of why Lucas went to work in the Architects’ Department of the London County Council which, in the 1950s, was the largest architectural practice in the world. But he did.

It was a move away from one way of making buildings, and towards to another way of making  buildings. It was the change from making little architectural one-offs for the benefit of wealthy individuals and one’s own reputation, to using one’s skill as an architect to improve mass housing prototypes for the good of many, largely anonymously. 

There’s more to see and hear here about the London County Council but this next image shows part of the Alton West Estate.

alton estate westI’m not so sure the Alton West slab blocks are ‘superficially modelled’ on Le Corbusier’s Unités d’Habitation for in some ways they’re better. Here’s a plan of Ud’H 1.0 – Marseilles.

Unite Typical Floor Plan

  • Instead of a central corridor every third floor, Alton West has gallery access every second. These corridors will be cold, but bright. Horses for courses.

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  • The apartments at Alton West are double storey but have no double storey living room (like Apartment A at Ud’H) or no double storey master bedroom (like Apartment B at Ud’H) for that matter. At last, somebody’s redrawn the section!

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  • The kitchens at Alton West are separate and have windows (and larders!). This was a buildings regulations requirement. There is a hallway – building regs again – and bedrooms of usual (regulated) minimum width. All quite nice really.

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As well as adpating PJ’s prototype for British building regulations, the London County Council architects were trying to improve upon what PJ had proposed. The interlocking plan, central corridor and double-height living rooms were never an option. The double height living/bed room is a waste of enclosed volume that could be more responsibly provided with a floor and used to house more people. It is also a poor use of surface area if regulations require your kitchens and bathrooms to have windows.  

But all of this is to miss the most important difference. At Alton West there are five slab buildings, not one. There are almost twenty point blocks.

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Let’s have a closer look at those point blocks.

point blocks at alton west

This is the sunny side.

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These buildings are stair-rich, presumably because of stricter fire code back then.

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  • All apartments are corner apartments, as you’d expect with four apartments and point access.
  • No two living rooms are horizontally adjacent.
  • Less space is used for circulation, even with the two stairwells.
  • Each apartment has a large hallway.
  • Whereas perhaps 80% of the apartments at Unité d’Habitations are double-sided and two storey, all Alton West Point apartments are single level and two-sided.
  • The service riser is beautiful.

During his time as an architect at the London County Council, Colin Lucas was also responsible for these two identical buildings.

Somerset Estate, Battersea

Somerset Estate, Battersea

Three floors of four two-bedroom apartments alternate with one floor of one-bedroom apartments. Apartments are arranged in a pinwheel arrangement, but split two to a side by the elevator lobby that has a single fire escape stair at one end, and a laundry drying room and garbage chute room at the other. This lobby is naturally ventilated and daylit. It develops the configuration of the point blocks at Alton West. Here’s a two-bed apartment plan.

A plan of a two-bedroom apartment.

And here’s what the kitchen looks like. The column from which everything below it in the plan above is cantilevered, is just out of the picture. Not shown in the plan above is the small window above the cooker, made possible by the pinwheel arrangement.

A refurbished kitchen with the separating partition removed.

These buildings are repeated across south London.

Twice more, as the Canada Estate in Rotherhithe,

Canada Estate, Rotherhithe

Two more times, as the Aylesbury Estate in Wandsworth.

Aylesbury Estate, Wandsworth

And six more times, as the Wyndham Estate in Camberwell.

Wyndham Estate, Camberwell

For about five years, I used to live on the 18th floor of Selworthy House in Battersea. I can testify to the solidity, liveability and humanity of these buildings.

Selworthy House

The view is also very nice, but that’s just an accident of history.

view of london from selworthy houseWhen these buildings were built, nobody valued views, especially those over Battersea, Rotherhithe, Wandwsorth or Camberwell.

rainbow over batterseaWhat impresses me most about the design of these buildings is how, by alternating three floors of two-bedroom apartments with one floor of one-bedroom apartments, Colin Lucas managed to make something special out of what must have been a very constraining brief. He did not have to do that.

These eleven buildings do not receive any mention in the history of post-war British architecture. They probably never will.

  • As part of the British government’s thirty-year war against its own people, the idea of social housing as a government obligation has been being erased from the consciousness of the people.
    1. Social housing has had its name changed to the less-loaded ‘affordable housing’. (The current mayor of London is at present attempting to redefine affordable housing as rents at 80% of market rent.)
    2. Whether past or present, highly-visible social housing is frowned upon. It is amusing to see how photographers contrive to omit the Somerset Estate towers from photographs of the (then) Richard Rogers Partnership’s Montevetro. Here’s a page of google images of Montevetro. This next image is from RSHY’s website.
      rogers stirk harbour young Here’s what looks like a planning application site elevation. Anything unpleasant is only shown in outline. One can almost hear the planners say “No higher than those hideous towers and you must respect the listed Church of St. Mary.” I have no respect for Richard Rogers or Montevetro.montevetro
  • Meanwhile, on the other side of town, Trellick Tower by Ernö Goldfinger is iconified as a Brutalist poster building by a famous architect in much the same way as PJ’s UdH is.Trellick-Tower
  • Robin Hood Gardens has people fighting its cause just as much for it being an important building by famous architects Alison and Peter Smithson as for any social significance it may once have have had. For the government, this is the rub – the very idea of highly-visible social housing is anathema.

ROBIN HOOD GARDENS

  • Part of this ongoing stealth campaign to discredit social housing is to encourage people to think of Brutalist architecture as nothing more than a dated stylistic choice.
    1. Any social worth (such as additional floor area) those construction choices may have generated is actively overlooked. Off-form concrete was honest about diverting money away from cladding and finishes and towards more useful parts of a building.
    2. It is easier to brand Brutalism a stylistic choice if it is associated with famous architects. We’re used to that as a concept.
    3. I suspect the Lucas towers are particularly reviled because that one extraneous design decision of the 3+1 repeat makes them very PROUD buildings. Once upon a time this conferred DIGNITY, but nowadays it seems to represent audacity.

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somerset estate colin lucas

So then, Colin Lucas

You chose to work largely anonymously and in a large organisation,
improving upon useful prototypes you were not afraid to repeat.
You believed that people’s lives would be enhanced by doing that.  

It is for these reasons that

misfits salutes you!

colin anderson lucas

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More From Less: The Principle

Here’s some outdoor space. Judging by the colour of the brick, the teapot, and the underused barbeque in the corner, it looks like we’re in England. The peripheral plants are doing their evapotranspiration thing but those benefits won’t be needed much when the average summer temperature is 22°C (71.6 °F).

small-outdoor-space-plantsThis outdoor space is enclosed by masonry on two sides and (almost certainly) timber on a third so any uncomfortable wind is probably blocked – along with any welcome breeze. We can’t tell the orientation from this image but, on evenings either side of summer, the thermal mass of the walls and paving will most likely make it possible to remain in this space for longer before someone suggests it’s maybe time you all went inside. But being outdoors is nice. There are many things we like to do outdoors whenever we can. The outdoor space in this next image seems to be in a climate that gets quite warm and, judging by the bamboo and the banana tree to the right, possibly quite humid as well.

Wooden-floor-outdoor-space Here, we can sit, eat and cook in this space, and even have a nap if we want. There are no walls and the floor is timber so there’ll be no heat retention due to thermal mass. The outdoor fireplace is probably something to look at whether functioning or not but it may help keep insects away. The absence of walls will allow any cooling effect a breeze brings. In this next image, one is protected from the wind and outdoor ambient temperature in this  space which is external to the main building aesthetically, constructionally, and conceptually – so let’s have a barbeque then!

fox_hill_web_024 This space can be used when it’s not desirable to be outdoors, even if standing next to a source of heat. Basically, we’re still inside. It’s the barbeque that looks out of place. Indoors and outdoors remain very separate, but at least we have a better view of the outdoors.

This is an unsponsored link to the full range of Viking barbeques. May as well.

viking barbeque

A whole industry of conservatories and big glass doors and windows has developed to allow people to have a better view of whatever outdoor space they have even if it has to be appreciated next to a fireplace. Nice window!

376221532_bb56cde250_oMoreover, a whole universe of architectural endeavour has arisen to give the impression the outside of a building is really an extension of the inside, even if (or perhaps especially because) it can’t be used for most of the year.

Pawson_House_London_by_Catherine_John_Pawso_CubeMe2 The outdoor space in the image above benefits from wind protection and the high-mass surfaces will re-radiate absorbed heat in the evenings to extend the period of comfort further into the evening or autumn.

This next image is a photo of a Japanese house – actually it’s no ordinary house, it’s  Katsura Palace doing the inside-outside thing that so impressed FLW and many other pre-21st and last-21st century architects such as John Pawson, designer of the space in the photo above.

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As far as the internal environment is concerned, its a bit like this next space – a room without walls. Let’s play “Spot the Viking!” Both rooms are most certainly lovely to be in when the weather’s nice but, when it’s not, you really don’t want to be there. In passing, these two images show how thermal comfort is blind to notions of visual beauty. I’ll have more to say on this later but, perhaps one day there will be such a thing as tactile aesthetics – the beauty to be found in a physiologically comfortable internal environment.

outdoor-kitchen-in-log-home1 But other than providing an alternative place to be when weather permits, what’s in all this for the indoor space? Nothing. We need to make a distinction between outdoor space that is no more than outdoor space the other side of a door or window, and outdoor space that also modifies the environment on the inside.  Consider this balcony. It provides the benefit of additional space and the effect of adding value to the apartment but it will also provide the summer benefit of shading the glazing and modifying the thermal environment of the that opens onto it – especially if the balcony faces south. 

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The thing about More From Less is that space that’s not fully enclosed and conditioned can substitute for indoor space some of the time and because it’s not enclosed to the same degree as internal space, can also provide climatic benefits for that internal space. In other words, space that isn’t constructed or detailed for 100% climatic adjustment can still passively benefit the internal environment.

Not all balconies, courtyards or rooftops have a positive passive effect. The courtyard of Ando’s Sumiyoshi House in Osaka will be hot in summer and cold in winter. Please visit this post on contraHABIT for a internal environment analysis of this house in terms of thermally active surfaces and flows, thermal comfort, natural ventilation, cross ventilation, stack effect and high mass cooling. (Nice work Taylor and good luck for the future!)

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If not much in the way of climate control, Ando’s Sumiyoshi/Azuma House is a reminder of how the Japanese manage to aesthetically, if not always physically, appreciate a certain poetry in ambient temperatures lower than many of the rest of us might. When it gets too cold for their houses to do the inside-outside thing, you’ll find Japanese in warm clothes huddled around a source of heat before getting quickly beneath a stack of futons in a shiveringly cold rooms at night.

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In this plan of a traditional farmhouse, Room 3 has an irori (see below) as a source of heat and most winter activity would take place in that room. Room 3 has no external walls. The remainder of the house is being used as a thermal buffer.

800px-Japanese_Traditional_Hearth_L4817 The vernacular housing of many countries will have similar examples of people retreating into the parts of the castle, mansion, or house that can be heated the most economically and efficiently. This sounds familiar. There might be something we can learn from this in terms of seasonally differentiated construction. Why should all of a house have to be used in the same way all the time and all through the year? After all, we all enjoy balconies but don’t expect to use them all year round. You’ve seen this plan before in It’s Not Rocket Science #7: Evapotranspiration. It’s the plan of an Egyptian courtyard house from around 3,000BC.

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That post mentioned how cool air is trapped in the courtyard overnight to keep the spaces opening onto the courtyard cooler and cooler for longer into the day. It mentioned how this effect is reinforced by planting a tree in the courtyard to shade it. This works well in places with a large diurnal temperature difference.

cropped-meybod2.jpg This climatic benefit only arises because the central space is not fully enclosed. So if you’re going to read a book, or have a drink and a chat or possibly a nap, do it in the courtyard! Not everything needs to be done indoors all the time. The lesson here seems to be have two types of space. Climate permitting, the light structure can be dispensed with altogether.

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The cave dwellings of northern China are another extreme example of this type of construction.

north china cave dwelling With these, there’s a heavy structure and huge thermal mass behind the building but this research shows that in front of the building it is still better to have a courtyard than nothing at all.

1-s2.0-S0378778801001451-gr4 This reminds me of Villa Vals (46°37’15.49″N,  9°10’51.36″E) which, it seems, is now a rental villa. Its famous courtyard faces WNW – and another mountain. In this photo, we’re looking south, down the valley.

1260367142-1villa-vals-search-7899 I don’t know if the courtyard at Villa Vals has a sufficient degree of closure to be a courtyard with any climatic benefits, but the principle is to have an outdoor area with a fair  degree of enclosure fronting a structure with a higher thermal mass. The actual materials  depend upon what’s available and the relative amounts of structures depend upon the climate. Temperate climates are easier to handle.

latapie planThe rear half of the Lacaton & Vassal’s Latapie House is not a courtyard, but nor is it a covered porch added onto a house. And nor is it merely a covered part of the garden. Whatever it is, it is an inexpensive structure with the beneficial effect of extending the range of usable temperatures of what could have been conventional garden, further into the evenings and colder months. It ameliorates wind and temperature extremes and modifies the environment on a seasonal as well as a daily basis. It is not a courtyard but an inexpensive addition that produces climatic advantages not unlike those producedby courtyards in hot, arid climates – except that the object is to trap warmth, not coolth. 

latapie

As is obvious from the plan, the house is not large, but this inexpensive addition permits a luxury of space and use that would not have been possible with more conventional materials and construction. The occupants have more options in terms of when and where to do what they do. Environmentally, the building has not used a wealth of resources. It is trapping heat to make its own volume more habitable and, even when it is unused, this effect carries over to thermally benefit the “main” building.

An earlier post mentioned how Lacaton & Vassal used this same principle in this project for an extension to a high-rise building.

interior view

This is a link to a paper titled “Building Performance Evaluation of Newly Built Greenhouse Residences in Terms of Heating Energy and Thermal Comfort”. These are some of its conclusions:

  •  A greenhouse saves about 25% on annual heating energy demand compared to a residence without greenhouse 
  • It is possible to optimise a GHR in such a manner that the greenhouse zone is usable for up to 750 hours a year, during 10 months

outdoor usage

  • The largest increase in usable time of the greenhouse zone compared to the outdoor climate occurs during the summer period

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  • A properly designed GHR does not exceed thermal comfort limits i.e. weighted overheating hours.
  • The most sensitive parameters are related to heat gains/losses and insulation.In conclusion, we can say that a GHR has benefits in terms of annual heating energy demand and usable hours of the garden zone; nonetheless, highly insulating is more effective as it saves more heating energy. If a GHR is properly designed it is possible to reduce the annual heating energy demand with an acceptable thermal comfort and usable outdoor hours. It needs to be addressed that a GHR has the benefit of the outdoor space, in comparison to other building concepts.

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It’s a field of study that promises to pay off, particularly for buildings in temperate climates. In the past, people would enclose porches with lightweight structures in order to make more usable space. Well, in the future, more of what is called architecture just might have to include these lightweight structures that people will have to make the best use of whenever they can. And during extremes when that’s no longer possible, they can retreat into the core of the dwelling while the external structure serves to ameliorate that internal environment somewhat. Lacaton & Vassal are pioneers in that respect. It’s more useful than Sanaa elevating the communal circulation space to the status of architecture.

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So what about this then? What’s going on here?

Seoul Light Section small

Seoul Light DMC Tower Digital Media City in Seoul, Korea combines technology and sustainability strategies to create a new model of super tall building design. 

A large central atrium spans vertically through hotel, residential and observation deck program areas to allow for penetration of natural light and air throughout the building. 

Air rises through the atrium in a natural “stack effect” and drives wind turbines at the crown of the building. Interior gardens at perimeter atriums act as “lungs” for the tower, providing air circulation and filtration for the varied functions.

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At 2,100 feet tall (133 stories), the mixed-use tower hosts a collection of green technologies, including solar panels, wind turbines, enhanced daylighting, and living walls. SOM anticipates that these strategies will reduce overall building energy use by 66 percent. “Original constraints on super-tall buildings were vertical transportation and structural requirements,” explains SOM design partner Mustafa Abadan. “Today, those requirements have become easier to solve with technological advancements, but sustainability needs to be addressed. We’ve shifted our priorities to environmental issues.”

Or how about this?

About halfway up the building at the hotel lobby, the more-traditional core is replaced by a 1,000-foot-tall vertical void. Roughly 60 feet wide by 100 feet long, the void is based on the principles of a solar updraft tower. Using the stack effect, air will be drawn into a collection area, where it will be heated naturally by the sun before it rises up through the tower to drive six horizontal-axis wind turbines, each 3 meters (about 10 feet) in diameter. SOM predicts that this “solar engine” will provide 3 to 5 percent of the building’s overall energy.

You can read more here, but I can’t help but wonder if this isn’t a lot of trouble to go to for a 3%–5% energy gain?

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Enclosing space is expensive. “More From Less” is about inexpensive ways that space can be enclosed for limited amenity and limited climatic/energy benefit. Using less materials or construction or whatever BECAUSE it is better to do so. It’s quite simple really. This building of SOM’s does not feature lightweight steel framing and polycarbonate sheeting on the outside and which might have worked just as well. Instead, what we have is a large central void almost fully enclosed by some rather serious (and seriously contorted) structure. If the object is to create a column of air that can be heated, then this is over-construction.  Why put a column of air in the middle of a building and then try to heat it from the outside? What were SOM thinking? I can’t believe an externally-mounted lightweight structure would not heat the air better and channel the hot air upwards just as effectively. Does it really take some swishy glass curves to make hot air go up? I find this building retrogressive in its use of maximum means to achieve not very much. The fact it won a a 2010 Chicago Athenaeum Green Good Design Award and a 2010 Eco-Structure Evergreen Award is deeply disturbing.

* * *

This is a design study for a building that I did, way back in 1995, exploring the poetics of energy-saving technologies. The point was to make PV panels look all sexy by using technological grandstanding to make allusions to Nature. In other words, the point was to make a big show of representing renewable energy rather than concentrating on actually generating it.

mainhouseTwo huge triangular PV arrays are each mounted on three hydraulically-extendable columns that extend and retract to enable the orientation and inclination of the arrays to track the sun to a greater extent than would otherwise be possible. The array planes are always parallel except at around midday and just after sunset, when hydraulic manoeuvring has to rearrange them so the one at the back is now at the front, not unlike a butterfly refolding its wings.

The entire point of this study was to give poetic representation to renewable energy devices without regard for the initial cost, the amount of embedded energy or the amount of energy actually produced. It’s bullshit really – using devices of virtue for an architecture of decadence. It’s not unlike the eating of songbirds or the eyes of peacocks, but it’s where we’re still at.

It’s Not Rocket Science #7: Evapo-transpiration

Speaking of gardens in the sky, I once lived in an apartment building that had one on the 25th-floor.

It was just a couple of floors missing from the building and wasn’t really integrated with any other space. It had ponds and palms and even a bit of grass and, on the whole, there was probably more evaporation than transpiration happening.

Transpiration occurs during photosynthesis when the plant’s pores (called stomata) on the underside of leaves open so the plant can intake CO2 and a little bit of water escapes when they do. This escaping water functions to transport nutrients from the roots to the leaves and also to cool the plant in hot weather.

dubai temperature and humidity

Dubai is hot and its humidity ranges between 40% and 85% with an annual average of around 65%. However, with summer temperatures in the 40s, the air can hold an enormous amount of moisture and still not feel humid. Singapore, by contrast, has consistently lower daily temperatures and consistently higher humidity. Plants don’t need to work as hard there to transpire. This is a good thing since transpiration would only add to the humidity.

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In my garden in the sky, the well-watered plants were shifting the moisture from their roots to their leaves and from there into the air. It did feel perceptibly cooler if there was no breeze or a very slight breeze. Air cooled by evapo-transpiration needs to be kept from moving away.

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This is the plan of an Egyptian courtyard house from around 3,000BC. 

This arrangement provides drops in air temperature of 10-20°C (18-36 F°) at night. As evening advances, the warm air of the courtyard, which was heated directly by the sun and indirectly by the warm buildings, rises and is gradually replaced by the already cooled night air from above. This cool air accumulates in the courtyard in laminar layers and seeps into the surrounding rooms, cooling them. In the morning, the air of the courtyard, which is shaded by its four walls, and the surrounding rooms heat slowly and remain cool until late in the day when the sun shines directly into the courtyard. In this way, the courtyard serves as a reservoir of coolness. [Natural Energy and Vernacular Architecture: Principles and Examples with Reference to Hot Arid Climates]

This is the town of Meibod, Iran. The courtyards are filling with the cooler night air. Notice how each of those courtyards also has a tree? After sunrise, photosynthesis will kick in again and the (denser) cool air held in the courtyard will be supplemented by air cooled by evapo-transpiration to extend the cooling effect further into the day. The shade provided by the tree will extend that effect further still. It’s a simple arrangement that works.

http://www.skyscrapercity.com/showthread.php?t=965506

http://www.skyscrapercity.com/showthread.php?t=965506

Less rural Persian gardens utilise the same principles but with more importance on visual beauty than cooling performance. As is the way.

iran2_025_l

http://www.reep.org/resources/islamic-gardens/design-elements.php

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Like the Persian courtyard house and its tree, certain combinations of plants and buildings work well for certain climates. Planting trees to shade east and west walls in summer is usual for mediterranean climates. In the cool temperate climates, deciduous trees shade south walls in summer yet allow light and warmth in winter. These uses are good but limited to instances where there is unbuilt land for those trees that are part of the climatic strategy. 

High-rise buildings usually occur in places where land is densely developed and trees are scarce. In any case, buildings these days tend to be taller than trees. If we’re going to put trees onto buildings, then we have to think about what it is that trees can do for a building and its occupants that some other type of solution – such as a shading device – can’t. We need to think about this because buildings and enclosing space of any kind is expensive. If we’re going to mess with the building to include them, then plants in general and trees in particular have to have some sort of quantifiable and unique benefits for the building and its occupants to justify their presence. Otherwise, it’s better to just go plant some trees somewhere, preferably nearby. 

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Yeang’s Solaris located in Singapore here at approx. 1°N is a case in point. The plants on the high end of the building face south and can’t provide much in the way of shade, the plants on the east and west shade every third level whilst, from the treed terraces on the north side of the building, it’s possible to look out over more trees!  I just don’t think these trees are there for their benefits of shading and evapo-transpiration.

Let’s move to Milan now and check out Bosco Verticale more closely. The architect says

On flat land, each Bosco Verticale equals, in amount of trees, an area equal to 10,000 sqm of forest.
The Bosco Verticale is a system that optimizes, recuperates and produces energy. The Bosco Verticale aids in the creation of a microclimate and in filtering the dust particles contained in the urban environment. The diversity of the plants and their characteristics produce humidity, absorb CO2 and dust particles, producing oxygen and protect from radiation and acoustic pollution, improving the quality of living spaces and saving energy. Plant irrigation will be produced to great extent through the filtering and reuse of the grey waters produced by the building. Additionally Aeolian and photovoltaic energy systems will contribute, together with the aforementioned microclimate to increase the degree of energetic self sufficiency of the two towers. The management and maintenance of the Bosco Verticale’s vegetation will be centralised and entrusted to an agency with an office counter open to the public. architects website

All good. The balconies are generous and, as is the Italian tradition, their construction looks solid and made to last.

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On his website, you can see that the architect has thought of the types of plant suitable for each facade orientation. I should hope so.

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The system of irrigation has also been thought through. Again, as it should.

03-Bosco-verticaleI wish the architect and building good luck. It seems a genuine attempt to fuse vegetation a building in a meaningful way. Tall buildings do strange things to wind so there are still unknowns such as how the trees will cope with wind not necessarily coming from the side and rain not necessarily falling downwards but fortunately, Milan is not a very windy city. The trees will tend to grow outwards towards the light so let’s hope overhanging branches aren’t allowed to become dangerously picturesque.

wind_speed_windSpeed_mph

The benefits of all these trees are shown graphically in the diagram below. We shouldn’t be too amazed by any of this. The trees will just be doing what trees have done for the past 400 million years (and, apart from the last 200,000 years of that, for no-one’s particular benefit). Of all the benefits shown, only the noise reduction effect is debatable but even if there is no great tangible reduction in the amount of noise, I believe that at least not being able to see the noise source does go some way towards lessening the awareness of noise. The rustling of leaves may even create a masking white noise. What about birds? Depending upon the type, the time and the amount of noise they make, birds may or may not be welcome. Birds can also be rather messy, but that’s their nature.

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The green box in the diagram above suggests that the experience of this building will be akin to that of being lost in a forest with its own microclimate, and isolated from the sights and sounds of the city outside. To a certain extent it will be, or at least it will be more so than most of the other buildings around. But what about evapotranspiration?

relative_humidity_percent_pct (1)Let’s ask weatherspark what the humidity in Milan is like.

The relative humidity typically ranges from 45% (comfortable) to 95% (very humid) over the course of the year, rarely dropping below 27% (dry) and reaching as high as 100% (very humid). The air is driest around March 23, at which time the relative humidity drops below 55% (mildly humid) three days out of four; it is most humid around November 1, exceeding 93% (very humid) three days out of four.

Thanks weatherspark. The blue line is the average daily humidity and seems rather high for transpiration to be considered a benefit. Milan has a Mediterranean-type climate with warm dry summers and cool winters with rain. It’s pleasant. The heat and noise of the city might irritate in summer on a humid day and so an amount of trees equivalent to 10,000 sqm of forest, a bit of evaporative cooling and various other benefits including biophilia in all its forms, is totally welcome. However, keeping it real,

it would be more welcome if the buildings did not stand in a park! 

A lot of money has been spent so that the owners of property within a high-rise building can have one of the attributes of land – the joy of having significantly sized trees outside one’s window. This type of joy does not come cheaply in a city. These plants have various marginal microclimatic benefits but their main appeal is just that. They aren’t exactly a part of the food chain or the waste cycle as they would be in truly integrated ecosystems like those that insects and plants manage to create for themselves. These trees are – I’m afraid to say – “Eco Deco”. There! I’ve coined the word and now offer it to the world.

* * *

The marketing website. It’s always cherry blossom time in renderland.

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It’s Not Rocket Science #6: The Stack Effect

The Stack Effect is when air is moved into and out of buildings by means of a difference in the buoyancy of the air on the inside and on the outside – between air that is colder and air that is warmer, in other words. Buoyancy can be either positive or negative – in the sense that warmer air can rise to be replaced at the bottom by cooler air, or cooler air can sink to replace warmer air at the bottom. Positive buoyancy is when warm air rises, and negative is when cool air something sinks. Got that? Both are good, if you’re trying to keep a building cool.


Or warm. Before I go any further, let’s not forget chimneys, sometimes called chimney stacks. Here’s a link to the history of the chimney. The first known English example of a chimney is at Conisbrough Castle from the 12th century, but they didn’t become common in houses until the 16th. Until then, life without chimneys was very very unhealthy.

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It still is, in many parts of the world. According to a World Health Organization report, “Nearly 2 million people die prematurely from illness attributable to indoor air pollution from household solid fuel use.”

Early chimneys were an improvement, but weren’t perfect. Count Rumford, whom you’ve already met, invented the Rumford Fireplace in 1797. He made two important improvements – one was to change the shape to direct more radiant heat back into the room, and the other was to restrict the size of the chimney at the bottom to increase the speed of the smoke going up the chimney. The streamlined smoke flow generating the stack effect had the added advantage of sending the non-smoky but heated air back into the room.  Importantly, existing fireplaces could be easily modified.

To many, these new and better fireplaces looked strange. They were shallow and their sides were angled and they were taller than they were wide.

Rumford Fireplace

Rumford Fireplace (Photo credit: bensheldon)

Lloyd Alter, over at treehugger, can tell you more about modern Rumford fireplaces. Interestingly, a fireplace has an optimum burn rate that is set to something like “roaring” – the heat should be burning off the soot at the front of the fireplace, as in the photo above. (Thanks for that Lloyd.)

Finally, to end this introduction to the stack effect, here’s a photograph you’ve seen before, of some chimneys that may have been admired by Walter Gropius for their stack effect. Or maybe not.

albert-kahn-ford-factory-1924

Conventional chimneys make use of positive buoyancy from the bottom, as do some solar chimneys that have been recently proposed to generate electricity.

English: Solar Chimney prototype at Manzanares...

English: Solar Chimney prototype at Manzanares, Spain. View from South 8km away  (Photo credit: Wikipedia)

Here’s a schematic configuration of a solar chimney power generation plant. [Thanks climateandfuel.] It’s usually proposed that the space beneath the heat trap be used to grow tomatoes. Whatever.

solar tower 200MW

Other solar chimneys use the sun to create a positive buoyancy in the air at the top of a chimney and thereby draw cooler air into the building to replace it.  Here’s a CAD model that’s easy to understand. Chimney heats air, causing it to rise and draw air through the building albeit at different rates for each floor.

English: Solar Chimney; CAD model (in TAS) use...

English: Solar Chimney; CAD model (in TAS) used to investigate solar chimney performance. Image by Nikolaos Angelis (Photo credit: Wikipedia)

This principle is used by the University of Washington’s University of Phase 1 Molecular Engineering Building (MEB) except that the rates are the same as each floor now has its own solar chimney. You’ll find more facts and performance data here. These stacks are really turbine ventilation inducers in which

a glazed panel was incorporated in the west-southwest orientation of the stack, inducing a solar assist to airflow by increasing the buoyancy of exhaust air during peak summer months.

zgf_uwmeb_3dsection_300Here’s a schematic of a building that uses passive energy to draw passively cooled air through a building.

English: This solar chimney draws air through ...

This solar chimney draws air through a geothermal heat exchange to provide passive home cooling. (Photo credit: Wikipedia)

It describes exactly the same principles known in Persia in the first millennium BC.

English: Diagram of a building cooled by a qan...

English: Diagram of a building cooled by a qanat and wind tower natural ventilation system. (Photo credit: Wikipedia)

Here, this windcatcher is coupled with a qanat which, you’ll remember from the post on yakhchal, is an underground canal (aka underground heat exchanger). Windcatchers come in many types depending upon their function and the direction or directions of the wind. They also trap a lot of heat because the µ-value of mud brick isn’t that high. This means that they function as solar chimneys when there’s no wind.

English: Windcatcher exhibit at the Dubai Muse...

English: Windcatcher exhibit at the Dubai Museum within Dubai, United Arab Emirates. The museum is located in the Al Fahidi Fort. (Photo credit: Wikipedia)

A windcatcher doesn’t have to be made out of mud brick to catch wind. However, if mud brick is what you have to build with, then you also have a solar chimney and a stack effect. This stack effect still exists when the tower is wind-driven but is insignificant compared with air movement generated by the pressure difference caused by the Bernoulli EffectGiven their names, it’s unsurprising that the stack effect of windtowers and windcatchers is overlooked but, even if wind had nothing to do with driving them, they would still be a tribute to human ingenuity and intelligence, providing cooling when and where it was needed.

* * *

The term ‘solar chimney’ threw up this image, from www.jeremylevine.com. I’m including it as an endnote because it seems to link the stack effect with recent concerns such as courtyards, gardens, biophilia, and SANAA.

Pocket Courtyard

Pocket Courtyard (Photo credit: Jeremy Levine Design)

Pocket Courtyard
An internal pocket courtyard acts as a light well, open air shower, and ‘solar chimney’. Working as a solar chimney the courtyard allows heat to escape up the vertical space, drawing cool air into the house through the oversize sliding glass doors that open up both ends of the house. This kind of passive/non-automated, climate control method gives the home’s occupants an interactive relationship with their microclimate that lessens their dependence on the carbon hungry air conditioning system.
The tree and plants act as ‘natural air scrubbers’, devouring the C02 and other airborne toxins, replacing it with oxygen.
Behind the tree is an open air shower tied to the grey water recycling system through a drain concealed under smooth beach pebbles.

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It’s Not Rocket Science #5: Night Sky Radiant Cooling

If ever you’ve noticed cloudless nights are colder than cloudy ones, then you’ve experienced Night Sky Radiant Cooling.  

The temperature of the surface of the earth is relatively constant so the amount of energy lost in the form of heat from the surface of the earth at night must be more or less the same as the amount of energy gained by the sun at the rate of approx. 1.5 x 10^19 kJ per day. Otherwise, the planet would overheat. Of course, one of our problems right now is that Earth is overheating a bit but, for the time being, we can still say that most of the Earth’s heat is radiated back into unheated space at night as thermal infrared radiation. Please allow me to introduce you to Count von Rumford.

Sir_Benjamin_Thompson,_Count_von_Rumford_by_Moritz_Kellerhoven

Two centuries ago he invented a more efficient and smokeless fireplace. For this, he received instant celebrity and the eternal thanks of ladies in London salons. He was a bit of an expert on heat transfer and, on his travels, noted that “the inhabitants of certain hot countries who sleep at night on the tops of their houses in order to be more cool and comfortable, do wisely in choosing that situation to pass their hours of rest.” He concluded that “frigorific rays” arrive continually on the surface of the earth from “the heavens” to cool the planet.

We know now that heating is the transfer of heat into an object and that cooling is the transfer of heat out of an object. Whether it’s heating or cooling depends upon the direction of the radiation but the effect of cooling is the same as if there actually were incoming “frigorific rays”. It’s not a bad way of thinking about night sky radiant cooling.

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A previous post about yakhchal described how, around 400BC, the Persians used night sky radiant cooling to make ice in winter. Yakhchal of the domed type were common in Yazd (smack in the middle of Iran now) where the climate was especially suited.

yazd location

Here’s a year’s worth of hourly temperature reports for Yazd.

hourly_temperature_bands_hourOfDay_hOfDay

FREEZING (blue) 0°C COLD (dark green) 10°C COOL (light green) 18°C COMFORTABLE (yellow) 24°C
WARM (light red) 30°C HOT
 (medium red) 38°C VERY HOT (dark red)  

We know the Yazd ice-makers knew about night sky radiant cooling because

  1. walls to the east, south and west sheltered the ice-freezing areas from the radiant heat of the sun 
  2. these walls also kept the air behind them still to further reduce the temperature of the air immediately above the ice
  3. the ice-freezing pools were covered with straw during the day to minimise heat radiation from the daytime sky
  4. this straw was removed at night to increase heat radiation to the night sky
  5. yakhchal were built on the edges of towns
    (In their paper, “Assessment of Ancient Fridges: A Sustainable Method to Store Ice in Hot-Arid Climates”, Mahdavniejad and Javanrudi report that yakhchal were built in the countryside because of their large land usage and the high cost of land in cities. Possibly, but if the ancient Persians understood about night sky radiant cooling then they would of course site their ice-making facilities away from cities and their heat islands.) This is a sketch of the ice house at the edge of the city of Kashan, from 1677.

ice house chardinIt’s well known that the process could produce ice even when the ambient temperatures were above freezing. Once produced, the ice was then moved to the yakhchal and stored through the summer. However, I don’t think the use of night sky radiant cooling ended once the ice was stored. In “An Overview of Iranian Ice Repositories, An Example of Traditional Indigenous Architecture”, Hosseini and Namazian state that

one of the advantages of these vaults was that they could be built step-like with stairs to help workers to cover the external crust of the vault with thatch [straw] to protect it from rain, snow, sun and atmospheric variations. They built smaller stairs between these stairs to make it possible for workers to ply. So people could maintain or repair them easily.

close up of ice house construction

http://www.andrewschneider.com/gallery/series-IranToYazd/index.html

If this stepped construction allowed the dome to be easily covered with straw during the day for whatever reason, then that straw would also protect the dome from daytime heat buildup. Moreover, and with equal ease, the stepped construction would allow that straw to be easily removed at night and so enable night sky radiant cooling to cool the dome during summer nights. I suspect this is what Hosseini and Nazamian meant by this.

In the heat of summers especially in central regions, the sun heats the Yakhchal dome. This method was also employed in order to prevent the ice stored to melt during hot seasons.

A 250 mm mud-brick wall has a U-value of 0.36 and a 350 mm wall has a U-value of 0.26.  [Ref.] Mud brick walls have low thermal resistance and are good at storing thermal energy. Unfortunately, this is exactly not what was wanted. Covering the domes with straw during the day and removing that straw at night is the sensible thing to do. The same process that worked when making the ice also worked when storing it. dome

Interest in night sky radiant cooling waned with the development of refrigeration.

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The following brief summary of late 20C developments in night sky radiant cooling applications is largely taken from the research “Potentials of Night Sky Radiation to Save Water and Energy in the State of New Mexico” by the architect Mark Chalom practising “the design and construction of environmentally appropriate buildings”.  

In 1967,  Harold Hay and John Yellott built a one-room, single-story building and on its roof was a series of ponds with a total area of 170 square feet and covered by movable insulating panels. This is all there was to it.

036-123-01afirst skytherm test building

During the day, the panels were closed so that the water would not heat up and at night the panels were retracted to expose the water to the night sky and radiate the heat it had gained during the day. In winter, the process was reversed and the water was exposed on sunny days and covered at night or cloudy days. Here’s what happened. It’s good.

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In 1973 they built a second house in Atascadero, halfway between Los Angeles and San Jose on the California coast. This time, the house was about 1,100 sqft and the water was contained in plastic waterbed-like bags. The system had no pumps, compressors, piping, or ducts, and could be easily operated by the occupants. Indoor temperatures stayed between 68°F and 72°F degrees while outdoor ambient temperature fluctuated between 32°F and 68°F.

skytherm-house041-008-01

It’s been heating and cooling without electricity for the past 40 years now. Its only recognition was the 1976 Bicentennial awards for the categories of environmental and solar energy. [ Ref. ]

Whilst Hay and Yellott were exploring night sky radiation cooling for roofs with their Skytherm houses, Steve Baer was exploring its use in Water Walls. His 1972 house in New Mexico used a stack of 55-gallon drums filled with water to provide thermal mass. The south walls were glazed with single-pane glass but had insulated, reflective covers that are lowered on sunny winter days and closed at night. [pic from here – thanks Batiactu!]

http-::www.batiactu.com:edito:prix-de-l-architecture-durable-2010---cinq--histoi-p14-26071

The inside.

water wall

Since then, Steve Baer and Zomeworks have developed the Double Play Solar Heating and Cooling System which is both a passive solar heating system and a radiant cooling system for buildings. The Double Play system uses one or more absorber panels attached to the south side of a structure. (Mark Chalom’s research has shown there is only a 25% reduction in the cooling effect if the night sky radiators are vertically mounted.)

Double Play test building

Double Play test building

There is water storage in the ceiling and radiator/absorber cooling coils on the roof.

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The system works.

double play

Zomeworks has also developed CoolCells which are highly insulated, passively cooled, outdoor enclosures that protect and prolong the life of batteries and low-power electronic equipment. They work too. [Here’s some performance graphs.]

cool cell

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In the climates that allow it, the use of unglazed radiators for cooling can provide large cost savings because NSRC is cheaper than refrigeration in creating coolth, and because pumps are more efficient than fans in moving it around. According to Steve Baer, the radiator plate becomes a “sensor” that reacts to the multiple weather variables surrounding it, like wind and cloudiness, producing a coldness that is the coldest useful temperature available at that moment. 

principles

Thinking about all the factors this way simplifies the calculation of the Night Sky Radiant Cooling Rate but, for us, all we need to understand is that night-sky radiant cooling uses 90-95 % less energy than air conditioners and 65-80 % energy than evaporative coolers to provide the same amount of cooling.