Greener than green - 5 Hanover Square

5 Hanover Square

As part of Green Sky Thinking Week I attended a seminar and building tour at the recently completed 5 Hanover Square in central London. Designed by Squire and Partners, the site is located within Mayfair's conservation area with listed buildings surrounding it. This in itself was a restriction. To add to that the client (Mitsui Fudosan) drove the sustainability agenda for this building demanding 10% renewables. 

Completed in 2012, the £26m mixed use development achieved BREEAM excellent for the office building and Code for Sustainable Homes Level 4 for the adjoining apartments. It looks like any other office building except it throws in as much sustainability into a building as it can given the site constraints:

• photovoltaics on the roof - these are angled at the optimum 30 degrees and are cleverly located to conceal the roof plant. They are also installed on the mansard roof.
• living wall - this is installed on the north-east (back) facade of the building and is fed by rainwater that is harvested and filtered
• post tensioned concrete slabs - these reduced the amount of concrete used since the slabs could be thinner and required less reinforcement
• 40% of the cement content of the concrete was replaced by GGBS (ground granulated blast-furnace slag), a by-product of the iron ore industry
• 25% of the aggregate content for the concrete was replaced with stent, which is a by-product of the China Clay industry
• 97% of waste was reused or recycled
• LEDs used throughout the building

mansard photovoltaic roof

photovoltaics on the roof

From the above list it's clear to see that there has been a lot of thought put into the reduction of energy use for maintenance of the building but also the embodied energy of the materials used. Simply looking at the concrete content alone we can see the significant carbon reduction by the use of waste products. This makes me think that concrete could be less of an evil than first imagined, if the correct 'ingredients' are used. 

Apart from the material carbon savings, there are perhaps more renewables that could have been employed on site. However, the location of the building is very restrictive. Wind turbines were considered as an early solution but testing on site proved to be less successful and therefore photovoltaics were chosen. The site's proximity to the Crossrail tunnels also prevented any technologies such as ground source heat pumps which could have otherwise been incorporated. 

This building is one of the few sustainable office buildings I have visited and in appearance it looks much like any other office building. This could be a good or a bad thing, depending on your personal opinions. I have the view that if a building can look like a 'normal' building yet out-perform and in a more intelligent way, then all the better. But then I also believe that the building should portray its 'green-ness'. It's a shame that the living wall is on the back facade hidden from sight. I would have preferred for it to be a prominent feature of the building and it's disappointing that it's not. Perhaps this was a restriction of the conservation area...

living wall

The office floors are bright allowing good views out to the city and also letting in plenty of natural light. The flats latched onto the end of each floor are somewhat disappointing as spaces. Although thought has been put into the specification, the stair treads are already chipping and the spaces are small and dark. I don't think it would be my choice of a place in the city. 

Despite my minor criticisms above, this project should be judged on its merits. It's a building that is working hard to be sustainable and so far it seems to be doing well. I guess the real test will come once the building is fully occupied and operational and whether it still performs as it's designed to.

The importance of the big C - Context

Ringroad (Houston) - image by Bas Princen

Whilst flicking through an old Domus edition I came across the image shown above which made me stop and wonder. It wasn't so much the photography that amazed me but the hideousness of the architecture presented here, I mean what exactly is this building trying to be? The thing that annoys me about this photo is the fact that this building is completely context-less, there is absolutely nothing that the building is relating to.

the deserted New South China Mall (image: internationalappraiser.com)

Following this I stumbled across an article I recently read on CNN about an abandoned Chinese mall which is now a "ghost town". The New South China Mall in Dongguan, China is the largest mall in the world based on leasable area. The idea of Chinese noodle selling billionnaire Alex Hu, was to build the largest mall in the world in his home town of Dongguan. It was meant to attract over 100,000 visitors a day, but 8 years after completion it is still as dead as the day it was built. The mall was to provide 2,350 retail spaces along with a cinema, restaurants and even roller coasters, but on completion in 2005 it was 99 per cent unoccupied! What was the problem?

Location, location, location!

Dongguan is a city with a population of over 10 million people, but the majority of these are migrant workers who work long hours in factories manufacturing products that are exported around the world. It's a city of poor, hard working people who lack the time and money to spend in such malls. But let's imagine for a second that they do, how would they even get here? The mall sits out in the middle of nowhere with no access by foot or bicycle and there are no major transport links, no airports, no infrastructure, so how are you meant to access it? If the people of Dongguan are unable to reach the mall, what hope do others have of accessing it? And herein lies the problem with this development - there is no understanding of context.

the deserted New South China Mall (image: internationalappraiser.com)

the deserted New South China Mall (image: internationalappraiser.com)

I find it frustrating to come across projects that are built without any understanding of the surrounding context - the context of the land and the people. New developments should be designed with thought given to its target user and how they would use the development. If there is no target user then surely there is no need to build?

construction outside Xian, China

Whilst I was in China I came across so much construction everywhere I went. These 'ghost towers' were cropping up all over cities and outside and around cities. But they didn't relate to anything. Context is so important for buildings to last and it's only a matter of time before these context-less developments are converted to rubble. How long can China really continue with the attitute of 'if you build they will come'?? The New South China Mall, for example, after 8 years is still not used as it should have been and the worst thing about this kind of development is that all those resources - the hours and the materials and the energy that have gone into its construction have gone to waste.

Perhaps this type of thoughtless construction is more common in China, but I have seen many buildings elsewhere that are just as bad and I cannot understand how people can forget about context.  It's not only the relation a building has to its immediate neighbouring buildings but it's also about the neighbourhood (in the broader sense). It's about addressing the needs of the local people because surely if there isn't a need, why build it?

Another example of an out of place building - the CCTV tower in Beijing, China

Paper bricks as a building material

image: blog.makezine.com

Two Nagpur (India) based researchers have developed a kind of paper brick that can be used for internal partitions, temporary structures and perhaps structures in earthquake prone zones in the future. It was a visit to a paper recycle mill by Sachin Mandavgane and Rahul Ralegaonkar which really got the ball rolling. The researchers from the Visvesvarya National Institute of Technology in India found that the sludge waste from the paper recycling process was being dumped in landfill and felt instead the waste material could be put to better use.

To produce the waste paper bricks, 90% recycled paper mill waste (RPMW) is mechanically mixed and pressed with 10% cement and placed into steel moulds until the moisture has drained. The bricks are then left out in the sun to dry. The semi-dried brick is then compressed further to remove more moisture and is then again left out in the sun to dry until solid. The end product is a recycled paper brick that can be used internally.

There are obviously drawbacks of the product which are mainly related to the material - paper - itself. The brick has excellent absorption qualities and thus retains water so cannot be used outdoors. The team are currently working on waterproofing the material so it can be used for external use. However, there are also great advantages of the product such as them being half the price of normal bricks and much lighter. The simplicity of production also means that they can be manufactured fairly simply using local labour. 

For more information see here

Oil can canopy

the oil can canopy (image: Sundeep Bali and Adam Rooney)

India is known for its can-do and mend attitude and so it's not a surprise to see an art initiatives such as Jugaad created by artist Sanjeev Shankar. Jugaad is a canopy made up of hundreds of re-used oil cans strung together and operated via pulleys and cables. I've previously blogged about Mumbai's recycling hub within Dharavi, and this isn't something that just happens within Mumbai but nationwide. It's the poor population's way of making money and a way for India to reduce its waste. Jugaad takes this activity a step further by using the re-used oil cans and converting them into an art installation for the wider population to see.

The installation was a way for Shankar to "interrogate the teetering ecology of the city through the prism of contemporary art". It is a truly ecological endeavour since local people from the village of Rajkori, just outside of Delhi, were asked to collect the empty discarded cans and to construct the canopy. It was a way of engaging the community. Ultimately the canopy is a piece of art and its beautiful yet still being functional.

Energy efficient....SUPERMARKET?

galvanised stainless steel wrap the timber structure of the supermarket (image: detail-online.com)

A supermarket that's good looking and has a brain? It seems, it's possible... Spar, one of the biggest supermarket chains in Austria has embarked on a programme to develop supermarkets that reduce their energy usage; "climate protection" stores. The third such store was completed in December 2011 in Graz, Austria, on a site 1.5km north of the old city centre, adjacent to the river Mur.

The supermarket is designed by LOVE Architecture and Urbanism, based in Graz itself, and they were chosen directly by the client as the architects. The clients requirements in terms of energy efficiency were a driving factor for the sustainable nature of this building. Alongside these requirements, the client was prescriptive about the interior layout of the supermarket but apart from that the architects were allowed freedom to develop the design of the building itself. This is probably what has allowed this supermarket to stand out from most dull and standard supermarkets we see.

large glulam beams support the roof (image: detail-online.com)

The load bearing structure of the building is monolithic timber with huge glulam beams supporting the roof. This soft core is wrapped on the outside with galvanised stainless steel cladding which responds to the post-industrial character of the neighbourhood. It really gives this supermarket a highly polished appearance, quite literally. The southern facade is left open in a fully glazed construction to allow solar gain. This glass has a solar protection coating as well as shading to prevent over-heating during the summer. The client set down strict time restrictions and so the building had to be erected within a tighter time frame. For this reason most of the building elements were prefabricated off site (concrete columns, timber beams and glazed elements) using working drawings and then assembled on site. This not only controlled the quality of these elements but also cut the amount of time spent on site. Only the steel cladding was manufactured based on site measurements since the dimensions of this were partly unknown.  

The building is smart in the way it consumes and re-uses waste energy. Photovoltaics in the car park and a hydropower turbine in the river Mur, adjacent to the supermarket, provide electricity. In fact the building runs solely on electricity without the need to directly burn any kind of fossil fuels. It is self sufficient in its energy needs and generates more than it requires. The energy loops employed within this building make it very efficient. The ventilation system is installed with heat recovery and the heating system generates two thirds of the heating requirements using exhaust heat from the cooling plant used to refrigerate food in the supermarket. This is a re-use of heat that would simply be wasted, instead it is fed back into the ventilation system. This heat is distributed within the supermarket using a thermally-activated floor slab which allows an even distribution of heat.  

energy flows diagram (image: Detail Green November 2012)

This building is beautiful and certainly the most aesthetically pleasing supermarket I have seen so far. And of course, its a bonus that it is smart in the way it functions. But such buildings do have a higher cost and this one cost approximately 6.5% higher than a conventional supermarket of a similar specification. However, this cost will balance out with the savings made from a reduced energy consumption and it will take only 3 years to reach this balance. I'm really inspired to see that finally something which I believe to be quite evil - the supermarket - is doing something right!

Learning from the 'Straw Bale House'

10 Stock Orchard Street in Islington, North London, is the combined house and office designed by and for Sarah Wigglesworth and her partner Jeremy Till. Commonly known as the 'Straw Bale' house it was an experiment in design at the time of completion. Having studied about this house during my undergraduate studies (where both Wigglesworth and Till were teaching at the time), I finally decided to visit the building myself on one of their open days earlier this year. More than seeing the building, I wanted to understand how it had performed over time and whether it had lived up to its green credentials.  

Upon first approaching the site, I can't help but think how tight it looks and wonder how well it functions against the railway lines adjacent to it. But as I go in through the gates, the site opens up into an L-shape with varying materials and facades on different elements, clearly used for certain purposes. When designing this building in the late 1990s the idea behind it was to create sustainable living within an urban environment. SW + JT wanted to prove that green building didn't have to be rough round the edges but could in fact be done using everyday materials in a simple manner.

gabion walls enclose the steel structure holding up the office

The L-shaped plan of the building helps define the living from the working space and also creates a generous open space at ground level in between the two. One part of the L sits facing the railway lines and is raised above the ground on stilts. The steel stilts are wrapped in recycled concrete filled gabions and have springs on top to absorb the vibrations from the passing trains. The facade facing the railway lines is clad in sandbags filled with sand, lime and cement which over time have turned into concrete in the shape of the sandbags. This facade provides the sound adsorption required on this side of the building. The other side of the L is where the living takes place. On 3 of the sides the building is wrapped in straw bales (not structural) to provide the thick passive building insulation requirements, with the south side having a  glazed facade to maximise solar gain. This is not rocket science, but sensible environmental design. These design decisions show that a sustainable building doesn't have to be a complicated building, it just needs to use natural resources carefully. These are technologies that are not difficult to implement, maintain or sustain and this is precisely the intention of the architects. 

the cement filled sandbags on the facade facing the railway lines

straw bales are left on show in one corner of the house

All materials used for this project were considered carefully based on criteria which included embodied energy, recyclability and distance from site. Apart from the materials, other technology used is rainwater harvesting, solar water heating and natural ventilation via the central tower and the stack effect. There is a green roof and a composting toilet in the house too - I wonder how much it's used? Although SW did emphasize that they only wanted the composting toilet but were told they would have to install a 'conventional' toilet too.

Walking around the house with SW as our guide, it's clear to see that she is happy with the house and definitely proud of what they have achieved. When asked if there are things she would change, she doesn't admit there are any, except maybe a slightly bigger kitchen! I'm interesting in learning about how the building has performed in the last 12 years and what informed certain decisions in the build. There are many elements of the house which work very well. For example, the house is raised above the ground providing an undercroft. This was done to match the buildings behind the site which sit much higher than the site for 10 Stock Orchard Street. Raising the building not only helped fit in with the neighbours but also provided a space underneath which is used for storage in a shed and also a place for the chickens to live. But one big advantage of this undercroft is a grill which sits on the ceiling of the undercroft and connects to the larder in the tower of the house. The cool air is drawn in up and through the larder keeping the food very cool therefore not requiring any refridgeration. This tower also helps to naturally ventilate the house. The undercroft also allows space underneath the house for a spare room, an office and utility spaces. 

the house with south facing glazing and the ventilation tower above

The rainwater harvesting also performs well providing water to irrigate the roof garden, for the washing machine and flushing the toilet. However, Wigglesworth mentions that the building 'leaks' meaning it lets out air therefore not being warm and air tight. But Wigglesworth doesn't see this as a problem, she says instead of 'turning on the heat, we put on a jumper'. This is a learning exercise, SW and JT have adapted to their experimental house and learnt to live with it. It is a way of living. As is growing their own vegetables in the garden plot on site. 

Although I am very impressed with the building and the innovation of the architects, I can't understand why there is so much steel structure within a house which is so clearly trying to be as low energy as possible. I ask SW exactly this question and the response is on the lines that they wanted a material that was controllable and accurate. This is understandable when working on a project such as this where there are so many experimental technologies in place. But I still think its a shame that such a high embodied energy product (albeit recyclable) such as steel had to be used where timber could do just as good a job and perhaps look more beautiful within its neighbouring eco-friendly materials. But that's just my opinion...

Completed in 2000, the building has performed well over time with the straw bales (one of the newest materials) not requiring any maintenance except a few bales being replaced. As is the case with many experimental builds (as can also be seen through 'Grand Designs'), the building took twice as long to build and was far over budget. However, it meets the needs of its client and users, it is sustainable and it provides a new precedent for sustainable design using basic principles. But more so, I think the ethos of Wigglesworth and Till is also commendable - they practice what they preach. They live sustainably - they grow their own vegetables and use their own resources (to an extent) through solar energy generation and rainwater harvesting. In addition they have cut back their energy used for the daily commute by bringing the workplace and the living place together. Could this be the perfect example of green living?

Concrete, concrete everywhere - could this be a Passivhaus?

This weekend I went to visit the construction site for the new Chester Balmore Passivhaus development in Highgate, London, as part of a new event called the 'Open Doors Weekend'. I was very excited to be visiting the site where the "UK's largest passivhaus development" would be completed in Spring 2013. The initial design was by Rick Mather Architects with Architype taking it through to completion, the scheme will comprise 53 housing units, with approximately 27 for affordable rent, 22 for private sale and 4 shared ownership (if I have remembered my numbers correctly!)

facade mock-up (image: aditi saxena)

On site we were taken around by the client himself and we began our tour with a short introduction about the scheme, the client and the architects. This was followed by a brief stop in front of a mock-up of the wall construction for the development (see photo above). This was to be concrete framed with a brick exterior and a large cavity in between to allow 'super-insulation'. I was intrigued. However, as we carried on the tour I found that there was not much more to excite me on this development. To begin with, this was the first Passivhaus building I had ever come across that was constructed fully out of concrete! Was there a sustainability agenda for this build? From my understanding of Passivhaus, the key principles of the system are:

• super-insulation
• minimal thermal bridges
• excellent air tightness 
• passive solar gains

You may notice that nowhere in this list is there a mention that the building should not be in concrete. But surely the whole point of principles such as Passivhaus is to reduce our impact on the environment! Passivhaus addresses more the issues of fuel poverty and our attempt of reducing energy consumption, but the main agenda behind such principles is to implement environmentally friendly solutions within architecture. It's great that we are trying to reduce energy consumption (since operational consumption is one of the highest contributors of greenhouse gases), but surely not at a cost of using building materials with high embodied energy. I understand the benefits of concrete and the issues related to high thermal mass and heat retention, so it's not a case of ignorance on my part.

We were told that this isn't a straw bale development, its not a 'grand design', but a conventional building that will simply perform to Passivhaus standards. I was curious to find out more behind the thinking and below are some questions I put forward and the responses I received (bear in mind these are not exact transcripts, but the general response!):

Q1: From my research, I have found that most Passivhaus buildings are constructed of sustainable materials. Was this ever considered on this project, for example timber construction including cross laminated timber?
A1: We didn't want this to be a special type of construction, we didn't want anything risky and that we couldn't achieve the airtighness with. We wanted this to be conventional type of construction and this is why we chose concrete.

Q2: I understand there is no central heating system within the flats, but how is the hot water heated? Have you employed any green technologies?
A2: It will be heated using gas. The council gets a good rate on gas.

Q3: Are there any other sustainable features within the development such as photovoltaics, for example?
A3: No, we wanted to achieve the air tightness criteria as defined by Passivhaus but wanted it to be a conventional build.

There were a few more questions to that effect but by this point I had heard enough. Except for ticking the air tightness and super-insulation boxes, this development was no different to anything else. The embodied energy of  the concrete frame would take years to be paid back even with the fuel savings of the Passivhaus standard.

This whole experience was frustrating since I was simply unable to understand how a project can aim to be so forward thinking in terms of using the Passivhaus standard, yet still be behind in some of the basic principles of energy savings. I don't claim to know everything about Passivhaus or sustainability within construction, but I do believe there is something not quite right about this project. It's disappointing for aspiring architects like myself to see that despite all the knowledge we have on sensible environmental design, there are still projects such as this one.

Update 12.11.12 following comments on this post:

• Timber (SIP) panels had been considered for the framing but were ruled out based on the complexity of the build with regards to requirements for thick insulation.  
• Overheating can become an issue with Passivhaus over time, so materials with high thermal mass can be beneficial. Also conventional construction is preferable in terms of cost and contractor buy-in. These are all fair points, but I still question, why concrete, why not masonry, for example?
• Photovoltaics will be installed on the project