Building your Sustainable Library

You wait a while for a good book and then two come along at once. 

I attended the UK launch of two different books relevant to you this week, the first was ‘Sustainable Cities – Assessing the Performance and Practice of Urban Envrionments’ edited by Pierre Laconte and Chris Glossop and published by I.B.Tauris ISBN 978-1-78453-232-1.

This is a portmanteau publication, containing a number of chapters written by other authors, some of which will have been published elsewhere in some form, but not all together as in this case, and not carefully considered for their relevant to this important topic. 

The question of sustainable cities, what defines them, what standards allies to them, how do we choose indicators to assess the, and when we build them how do we know we have succeeded, are all questions tackled by authors in this publication. Given that we have now passed the point at which 50% of the worlds population lives in cities, there is hardly a bigger question for sustainability specialists to work on. If we can crack this, we can avoid runaway climate change.

Authors include Dr. Kerry Mashford, the late Sir Peter Hall, Chris Glossop and Dr Ian Douglas.

I also attended a lecture given by architect Stefano Boeri on his recent project in Milan, Bosco Verticale. The event was hosted by the Engineering Club at the Congress Centre. (A few architects turned up)

Bosco Verticale translates to Vertical Forest, and his two buildings in Milan, evenly constructed for Hines, and then sold on to Qatari Diar, demonstrate what he means by this. Each apartment has a tree on the balcony, several metres tall, together wth a quantity of shrubs and smaller plants. The publication ‘un Bosco Verticale, a vertical Forest- instructions booklet for the prototype forest city’ published by Corraini,  ISBN 9-788875-705411 was available on the night and furnishes a lot of background information to the project including the following numbers. 

The project provides two hectares of forest and 8900 Sqm of balcony area.

This includes 711 trees, 5,000 shrubs, 15,000 perennials, absorbing 19,825kg of CO2 per annum.

There are approximately 1600 birds and insects (although how they could know this is not explained!) This includes a box of ladybirds imported from Germany to eat aphids and other pests. (I don’t know why they needed Germany ladybirds)

The design uses 94 species of plants, giving it a very high level of biodiversity.

The trees are planted in steel-lined planters to prevent the roots cracking the structure, and they are loosely tied back to the structure in case they could be blown off iin hurricane level winds. The steel-linings will also constrain the growth of the trees so that they cannot get too big for the space available or too heavy for the structure. They are a bit like enormous  bonsai trees. They are maintained partially from the balconies, but the outer sides are pruned by gardeners that abseil down the outside of the buildings twice a year. While this might sound outlandish, consider that many glass buildings are routinely maintained by abseilers. 

The result is extraordinary, a pair of buildings that look like no others, and a second project is underway in France. Stefano was quite straightforward in admitting that it took some time and a lot of effort to convince his clients that this could work. There are elements of what was built that he will change the second time, and he has plans to continue to develop  the idea on a larger scale.

He was asked many times by the audience about squirrels, which he was not in favour of, but which he expected to arrive anyway, and also about fruit trees, as none of the species used are fruiting trees. He cited concerns about the dangers of falling fruit as the reasons why they weren’t used. This sounds to me like a problem that could be solved, and would add a further beneficial dimension to what is already a beautiful and convincing idea. 

This is an inspiring idea and one that merits your attention.


Image https://commons.m.wikimedia.org/wiki/File:Bosco_Verticale_from_UniCredit_Tower,_Milan_(17591709258).jpg

A new entrant to the UK Housing Sector

You would need to have been living under a rock to have missed the arrival of Legal & General on the UK Housing scene. From a position of no involvement in housing, L & G are now set to become one of its biggest players. How has this come about? Because of the housing crisis.

L & G (and others) see the current UK housing market as an opportunity. With a backdrop of strong demand, rising prices and an existing set of housebuilders which are unwilling or unable to ramp up production to meet the demand, this looks like a market that is ripe for disruption.

Instead of going down the normal route for a new entrant to the market, and playing the same game as the uincumbents, L & G are going for broke. They have invested in the largest factory in the UK, bought a Cross-Laminated Timber production line, and just in case you missed the point, are setting up a plant to manufacture CLT to guarantee their source of supply. They are doing nothing by halves.

The plan is to produce and supply 5,000 homes per year, or more from the factory, and to supply all of it using CLT. Thereby adding the same output to the industry as ten additional Barratt divisions, or a Redrow to the housing industry.

They don’t intend to compete directly with the housebuilders, because they are not going to be selling a comparable product at a comparable price. Mostly they will be developing to own and rent their own housing stock.

The interesting elements of this is because much it will remain in their ownership, it is open to investment. The U.K. Housing industry has not been open to investment since we decided that we had to own our own properties. Now that we have accepted that this is both unwise at some stages of our lives, and impossible for many people, there is a clear and undeniable need for long term home rental. A pension fund looks at long term home rental and sees something that it can invest in.

The housebuilders have shareholders too, but their focus is on paying out dividends each year rather than owning assets thta appreciate. Although housebuilders do won assets in the form of land, and it does appreciate, it doesn’t have nearly as much value when traded as it does when it has homes built on it. This makes the housebuilders a poor investment risk compared to rental property. Rental property accrues value and brings in an income every year, so there are two opportunities to make a profit, both in the short term and in the long term.

In Germany, a large proportion of housing supply has pension fund backing. In the UK it is almost non-existent due to our historical distaste for renting. This is all going to change and there is a lot of headroom to grow into for investors.

Another impact from the pension fund is that they care about the long term, their business model means that they have to. If you are paying out pensions to thousands of people every year, you have to be confident that the money will be there for them. This means that they care about what homes are built from, how well it will last, and how sustainable they are, because it matters a great deal to them and to the people who are paying into their pension funds. Who would invest in an oil company now? Or a coal mine? But housing in the UK, with strong demand set to continue into the foreseeable future? That looks like a safe bet.

Ask not what Drones can do for you, but what can you do for a Drone.

Musing over the idea that drones (and by this I mean the little ones, usually small quadcopters, not multi-million pound aerial weapons flown by remote) will have a major role to play in modern urban societies, I concluded that it would be both fun and instructive to work through just what their role might be. 

Both Google and Amazon are experimenting with drone delivery systems and I can see the appeal of this immediately. Instead of having to wait a whole day for gratification, the lengthy gap between ordering online and when our newly purchased parcel arrives, we can have our gratification almost immediately if we can organise a drone to deliver the purchase instead. We see that thing online that will make our lives either complete or a bit less incomplete, we buy the thing, and a drone delivers it to our door a mere hour later. 

Lets just take it as read that this will happen in any case, because if for no other reason, there are a lot of pizzas that need delivering every day, and this would take a lot of maniacs on scooters off our roads, and thats the thin end of the wedge. With the growth of online shopping I have heard a TFL* representative say that 30% of Londons traffic is delivery vehicles. Even if we took 50% of the vans off the road, we would reduce congestion a lot, reduce emissions a lot as most vans are diesel powered, and the streets would be quieter and safer. Apart from the hum of drones that is. Perhaps the pigeons would disappear too, perhaps there would be too much aerial traffic for them to feel comfortable, one can hope.

But there are a lot of problems to be solved and barriers to that future. 

Legality

They’re illegal, and cannot be flown near to people, which is a bit of a problem when you want them to get close to people to deliver goods to them. I think this will go away presently as the software systems running on the drones enables them to be more or less autonomous and able to avoid crashing into things or people. If cars can be considered safe as driverless objects, then drones shouldn’t present much of a challenge, being much smaller and lighter, and posing much less risk to human life. Lets assume that that challenge is surmountable.

Location

Drones don’t currently have much of a range from the signal that controls them, which means that if you are a kilometer away from their controller they aren’t much use. I think that this can be dealt with by allowing the drone to control itself and by having a distributed network of guidance, like cellular telephone masts, that provide locations to the drone as it comes close to the mast. We use these masts to locate ourselves with smartphones, so why not drones too? To get it to deliver to our houses we just need a way to broadcast a signal to it that it can recognise, perhaps like the one created by our WiFi routers?

Distance

Being battery powered the current quadcopter drone designs are limited in terms of the distance they can travel and the loads they can carry. Battery technology is getting better, so distance will grow over time. The location masts or beacons used above to tell them their location could also provide charging points, so a tired worn-out drone could stop off for a quick gulp of electrons on the way home after delivering your pizza, book, fresh coffee,..whatever. To take on heavier loads drones could cooperate. This video by ETH shows a group of drones constructing a rope bridge, and this one shows another team creating a structure using bricks. The relatively straightforward task of delivering a parcel looks rather easy in comparison.

Identity

One of the major problems with drones is privacy. People don’t like the idea of a machine equipped with a powerful camera flying over their heads on a daily basis. This seems a bit Luddish to me, after all, in our cities we are surrounded by cameras in the hands of everyone we pass as well as those on the streets and buildings. But lets address the problem anyway. Imagine a scenario where the drone is autonomous, and not under control by any external agent, as it winds its way from depot to you. It doesn’t even need to go to your house, if you are in the park having a coffee, it could deliver the pizza directly to you. What the drone needs is autonomy, and a way of getting an anonymous set of directions to you. It need never know who you are, or where you live, and even better, it need not know what it has delivered to you. This will help to avoid the problem of Amazon and Google knowing everything you ever bought so that they can try and sell you a duplicate of everything you own. (why don’t they try and sell you something you haven’t bought?)

Delivery

Lets take a scenario where you order a pizza and its awaiting delivery at the ‘restaurant’. A signal is sent out that a delivery needs to be made, and the nearest drone accepts the job in the same way that a Uber car would. The shortest distance to pick up the pizza would offer the cheapest transaction cost. The drone collects the pizza, and is given an electronic token at the same time. This was created by you when you ordered the pizza. Half the token goes to you, and half to the drone. You broadcast the token from your location and the token is passed from one point on the network to the next, every time the token is passed on it gets a bit added by every node on the network. The network propagates the token from one node to the next indiscriminately. This enables the drone to follow the trail back to you by seeking a broadcast token that is shorter than the one it has picked up from the network and which matches the other half of the token it already has. It will find its way to you without knowing who you are, or where you are. 
 

Esch bubble represents a location beacon, such as a wi-fi router., the routers broadcast the destination to the drone, and the drone follows this to you, wherever you are. The box at the top left is the warehouse sending in the message, the box on the right is you waiting for the delivery. Drones already in the network pick up the message signal, follow it to the warehouse, pick up the package and deliver it to you.

 

Security

In the same way that BitCoin has developed a security system that is distributed, and every bitcoin node knows how many bitcoins there are, and who owns them, without being controlled by a central source, drones could carry out the physical transactions managed by a similar system to the electronic transaction. In a nice parallel where BitCoins enable Payer A to use currency B to pay C, the drone can carry the package from C back to A using the network B. Read this article on blockchains and BitCoins and you will see what I mean. This method would prevent anyone knowing which drone was carrying which package, and who it was intended for. The only way someone could steal your pizza would be to follow you home and steal it from the drone as it delivered it to you. Of course there will always be people who will snare a drone for whatever it happens to be carrying, but at least they won’t be able to steal on demand. 

Physical Implications

A drone needs somewhere to land a drop off its parcel. It needs a flat surface to land, and if the person for whom the delivery is intended isn’t there, it needs an electronically linked drop box where it can leave your parcel. It could lock the box with its half of the electronic delivery token, and you can unlock it with your matching half when you get home from work. But the box needs to be big enough to accept your pizza, post, packages and needs to be somewhere that the drone can get at but where other people cannot. For apartment buildings this would ideally be the roof, where a landing platform and a set of drop boxes could be located without too much difficulty in many flat-roofed apartment buildings. 

Perhaps one day drones will be able to post letters through your letterbox, if you still get any, any that you actually want to read that is.
*Transport for London

VELUX Daylight Symposium 2015

The Location: The event was held at the Tobacco Dock, a reminder that some reused buildings provide stunning locations for events, and in this particular case the event was held in daylight. It may sound obvious, but most conferences are still held in locations where daylight is excluded, in case it interferes with the presentations. The usual result is a lot of sleepy attendees watching a lot of fairly tedious slides. When light levels are lowered, our bodies natural inclination is to go to sleep, a fact that the designers of most auditoria seem to have ignored. 
The lantern lights of this tremendous building were modified by simple banner-like screens to prevent glare and the two days were spent with the delegates bathed in full daylight but still able to view the screens. I cannot emphasise enough how much nicer an experience it is to spend a day in this way, rather than buried in the bowels of some convention centre.

  

The Content: The Daylight Symposium is a unique event, bringing together the worlds leading experts in daylight research and practice. It happens every two years and brings together the authors of CEN standards, the authors of daylight calculation software, the research community working on the effects of daylight on productivity and well-being, and the authors of guidance on the provision of daylight in design. There were also a few architects like me who tried to keep up with the science and not make fools of ourselves by asking really stupid questions, like, ‘what is the difference between lumens and luminance?’*

Some Conclusions

Over the two days I listend to a diverse range of speakers, from all over the world, many technical, some beautiful, all of them interesting. There were some particular highlights for me.

Daylight Autonomy, The CEN Daylight Standard draft appears to signal that the time has come to move on from Daylight Factor as a means of measuring daylight in architecture. Daylight Factor is a simple metric that predicts the amount of daylight in a room expressed as a percentage of the daylight available from an overcast sky. There are several problems with this.

Daylight Factor is not comprehensible to most people, including many professionals. It doesn’t relate either to the location of the space being examined or to the likely weather conditions in that location. So a room of the same size will achieve the same results in Iceland as in Uganda, despite the available daylight being quite different in the two locations. It doesn’t take into account the availability of greater amounts of daylight and sunshine available under typical weather conditions, so a part of the country where there is routinely a lot of sunshine will appear to perform as well as an area that has much less sunshine. As overheating becomes more of a problem, this is counterproductive. 

The CEN recommendation, based on several presentations during the event, is that we move to a measurement based on the availability of light in the room for a proportion of the day. This is similar to Daylight Autonomy, the US standard used in the LEED sustainable buildings assessment method. The draft CEN standard will suggest that we use a measure of the light levels in lux in the room expressed as the time that a desired light level is exceeded in a proportion of the space. The example given as a minimum is 300 lux in 50% of the room for 50% of the time. 300 lux is enough light to read, write or carry out office work, so it is adequate for many activities likely to be carried out at home. 50% of the space allow for variations in the lighting, particularly spaces only lit from one side. 50% of the time allows for variations over the day, so a room that is well lit in the morning can still comply with the requirement, as well as a room that is well lit in the afternoon, or early evening.

The draft CEN standard suggests that there could be three levels of such a standard, a minimum, set at 300 lux, a good at 500 lux and a high at 750 lux.

Rendering with Daylight: A particular bugbear of mine is architectural rendering that shows interiors bathed with light, when in fact such light is either impossible or unlikely at best. This doesn’t do anyone any good. Architectural rendering has a purpose, but that purpose should not be to mislead the designer or the client. It was heartening to see a presentation of Keyshot, a photorealistic lighting tool that can interface quickly with the VELUX Daylight Visualiser. They are both written by Luxion and they are now capable of interacting with each other. The VELUX tool can check the daylight in the room and Keyshot can produce a verifiably accurate daylight render. It can also deal with materials,textures and artificial light, but the important point is that it renders daylight accurately so that designers can check what actual difference their design changes make to the spaces rather than being fooled by a rendering engine that allow the designer free rein with the amount of light available. (In case you think that software doesn’t mislead, and I am overstating the point, one well-known and widely used rendering tool allows the designer to make the sun bigger!)

Thought Provoking: Paul Bogard: The organisers, VELUX, like to intersperse the hard science with some thought provoking speakers, and this time there were two presentations, one at the end of each day. The first by Paul Bogard was not about daylight, but about darkness. His book, The End of Night concerns the fact that most children in developed countries have no idea what a starry sky looks like. I was lucky enough to grow up in a rural area where starry skies were often visible, and the full majesty of the universe could be felt by anyone coming outdoors after dark. Today there are few places in the Western world where this is possible without having to get into a car and drive long distances. Will we end up in a world where fewer children want to become astronomers because they are unaware of the possibilities, or fewer philosophers because they haven’t seen how small and insignificant we are in the grand scheme of things. Paul points out that much of the problem is caused by security concerns and homeowners and property owners being sold lighting systems that waste a lot of light, and don’t even provide good security.

Thought Provoking: Olafur Eliasson: The presentation at the end of the second day was by Olafur Eliasson an Icelandic artist who, among other works, has filled the Tate turbine hall with a sun, and put large chunks of Arctic ice outside a hall where one of the COP talks was taking place. Bizzarely, one of the delegates contacted him a year later to ask him to bring the ice to the next COP. He had to tell the delegate that sadly, the ice had melted, but that there was more available in the Arctic.

He presented his kickstarter project with Little Sun which aims to bring artificial light to countries where children currently cannot read or study after dark unless they use kerosene lamps. His talk was deeply contemplative, almost mystical. His use of language was amazing, given that he works in Berlin and was born in Iceland, so must use at least three languages every day to express the most complex of thoughts. Two thoughts that stayed with me are:

The Shaping of the world is the creative act, and not the work itself.

Cultural institutions allow people to share without agreeing.
* ‘Lumen is the total luminous flux emitted by a light source, and luminance is the amount of light emitted from a surface in a particulat direction’ Obviously!

MMC: Evolution or Revolution?

 I spoke last week at the Residential Construction Network hosted by the RICS in Westminster.
The three speakers were myself, Paul Inch from Innovare and Jean-Marc Bouvier from Nudura Insulated Concrete Formwork.
I introduced the topic by pointing out the continuing and rising gap between housing production in the UK and housing need. See image below. At current levels of construction and demand we will see two million people short of a home by 2030.
 The Housing Gap
My view is that offsite construction is needed to fill the gap because the gap is mainly made up of people who cannot afford to buy their own homes at current prices, and are unlikely to ever do so. Affordable housing including shared ownership models needs to be provided for them by Registered Housing Providers(RHP’s) and by the Private Rental Sector(PRS).
There is little or no motivation for the private sector to build more housing than their current capacity to deliver. The hostorical figures show that speculative housing rarely delivers over 150,000 homes per year. They are making good profits with current numbers, so why would they change a formula that is working?
The current housing industry based on speculative housing for sale tends to use traditional construction methods as the average rate of sales on sites is slow and building faster doesn’t actually make much difference to them. What does make a difference is changing labour rates, particularly in a boom which makes their land and construction pricing difficult to predict. The regular boom and bust cycle in UK housing means that they are unlikely to either dramatically change their levels of housing supply or change the way that they build.
A possible solution to the problem is to marry up the large balance sheets of local authorities and RHP’s and use additional borrowing to construct homes offsite. This would require decisions on the part of these large clients to support a new industrial sector, housing manufacturing. A medium sized factory could supply 2,000 homes per year, but investors will only commit to constructing such facilities with a confirmed pipeline of demand. There can be competitive tendering, but between similar factories, and not between factories and site operations. This is not to promote more expensive housing, but to give factories the support they need to get going. Clients need to decide that this is the route to deliver affordable housing and government needs to support them in any way it can.
Ten new factories every year for five years will deliver 50,000 new dwellings that we are currently not building, from finance we are not using. That will go a long way to closing the gap in the housing supply. Once the market in offsite manufacturing is more mature, it can expand to take up the remaining gap and supply products to the sale market. The factories can be distributed across the country to places where there is greatest housing need and staffed by locally trained people. These plants can be set up and be running within a year, particularly if they use timber frame manufacturing. The jobs will be stable long term ones, possibly as many as 100 per factory. Thats 5,000 jobs within five years without counting the site works and the finishing trades on site. Its not wise to construct entire dwellings in factories, some work needs to be done on site to prepare foundations, and to finish the facade and roof on site.
Paul Inch, Business Development Director, Innovare
Innovare are one such factory, constructing homes and schools from their factory in Coventry using Structural Insulated Panels. They have a strong history of building high performing homes and buildings that provide very well-insulated building fabric. This is achieved by constructing using large format panels containing the building structure and insulation. Speed of construction is much faster than traditional methods and the quality of the final building is higher, particularly delivering low levels of air leakage and reducing the heating demand from the finished building.
In Paul’s opinion, RHP’s should use the market to deliver their buildings and not try and go it alone. There is a lot of manufacturing skills in the market and it is best left to the market to provide it rather than try and bring it in-house as some RHP’s have done.
Jean Marc Bouvier Director of International Sales and Business Development
Jean Marc Bouvier from Nudura Corporation, a supplier of Insulated Concrete Formwork products described their system. It provides large insulation panels that fit together much like Lego and are then filled in with poured concrete to form the walls of the design. It is a very rapid form of construction and delivers very high performance buildings. By using large lightweight elements the construciton process is safer and quicker, and because of the pured concrete there are no air gaps in the construction. Another benefit is that it is very resilient to wind effects and is being used to construct storm shelters in the southern regions of the US. Like SiPs it enables a highly productive delivery, with far fewer man-hours required to deliver the finished building compared to traditional building methods.

Zero Carbon(2016) Exemption Proposals

The plan to exempt small sites from zero-carbon legislation strikes me as being a total waste of time, energy and money and I cannot fathom why DCLG are wasting their precious time (and mine if it comes to that) with it.

The consultation document can be read here. The main elements are
– The proposal is to exempt small sites from the Allowable Solutions element of the Zero Carbon(2016) proposals. That is, the CO2 offset payment for that CO2 not mitigated on site by the development multiplied by 30 years multiplied by the agreed cost of CO2 per tonne.
– The consultation seeks views on the proposals including
The definition of small sites
Whether the exemption should relate to developers who are small or to any developer developing small sites
Whether the exemption should relate to Allowable Solutions only or whether the exemption should relate to Carbon Compliance as well
How long a time-frame the exemption should last for.

The problem I have with this is: where is the evidence that this is going to promote development? I haven’t seen any. Figures from the consultation document point out that 10% of planning applications in the UK measured by unit number were for single dwellings. That amounted to 24,000 units. So that tells me that there is a lot of activity in this sector and we can expect that to continue.
The Allowable Solutions impact of about £2-3k per plot will act as a small disincentive to development, but since many of those applications (my conjecture) are for the people who will actually live in those homes, the additional costs can be weighed against a lower cost of living for the occupants. The savings in fuel bills over the lifetime of the dwelling will pay for the relatively small additional cost. This is a calculation that many people will be able to do, and probably will realise that if they increase the build specification slightly they will reduce the Allowable Solutions costs and save themselves even more money. This seems to me to be a virtuous circle. People build more efficient homes for themselves, and they save money over and lifetime and there is less CO2 produced. This sounds like a market actually working. So why does the Government think that this is a market they need to interfere in before they actually have it in place?
The likely time frame would be from 2016 until the next issue of the Building Regulations, around 2020. This would allow the costs of the Zero Carbon (2016) to drop and the costs of Allowable Solutions to be absorbed. Again this seems to me to be counter productive. The way to reduce the costs of the Zero Carbon (2016) standard is to have everyone use it as soon as possible. This will bring down the cost of the insulation and window products that are needed to reach the standard, and then they will be available to all and not just the large housebuilders with very cost-effective supply chains. This proposal risks creating a two tier industry with higher costs of smaller builders and lower costs to larger builders.
The problem lies with the speculative nature of so much of our housebuilding. The builder of some of these small plots doesn’t know who the buyer has, and therefore has no interest in how that buyer lives in the home. There is no way for the lower costs of living in a more efficient home to be passed on to the developer in a beneficial way. A developer cannot build a more efficient home and offer it on the market for a small premium, this benefit is simply not recognised in the valuation of a property.
So, can I suggest that a more effective way for the Department to spend its time and mine, would be to investigate ways of making the speculative housing market function as a better market instead of trying to undermine those elements of future legislation that are likely to help it to function as a better market. But in an election year, perhaps that is too much to hope for.

World Sustainable Building 2014 (Barcelona)

The Summary:

This was an enormous conference with a concentration of expertise on sustainable buildings unlike any other conference I have attended. The messages from the conference were many, including the following which particularly struck me:

– we have too many different approaches to sustainable buildings across the EU, we need to coordinate approaches to make training and cooperation easier, this does not mean simplify! But there are some elements of different approaches that can be standardised to give a stronger platform for the other areas that need development. For example operational energy calculations could be standardised, but embodied energy tools are too early in their development to do this yet.

– our approaches to sustaianbility are often impenetrable to people outside the confines of specialisms. A result of this is that around 1% of the new buildings in Europe are given a sustainability rating at all. We need to make our language and approaches more comprehensible to the end user and to the market.

– LCA in particular is complex and time consuming, and the results are not always useable. We look forward to the wide use of EPD’s.

 

The Detail

This was my first visit to this conference, there were 1400 delegates  from around the world, many from Spain, a lot from the EU, but also from Hong Kong, China, India, Korea, the US and many more. I was mainly there to attend a meeting of the ActiveHouse Alliance. This is a pan-European alliance of companies and organisations working towards a better definition of sustainable buildings using Comfort, Energy and Environmental scores as a rating system. I am on the Board Advisory Committee which means that I am helping to guide the direction of the standard, having beein involved in the design of the first two homes constructed to meet the standard in the UK.

The conference spanned three days, I attended for the first two.

On the first day we held the ActiveHoues BAC meeting and on the morning of the second day we held an ActiveHouse Symposium, bringing together some of the research that came from the first completed projects across the EU. The sessions included observers and commentators as well as presentations from the projects themselves. I summarise here some of the comments and ideas that struck me particularly, these only represent a tiny fraction of the ideas presented, and the sessions I attended on the two days only represented one sixteenth of the sessions available!

ActiveHouse Symposium

From the ActiveHouse Symposium one particular comment that has stayed with me from this session is from Nils Larsson from IISBE, Canada, who said that ‘individual family homes cannot be described as ‘sustainable’, because a single dwelling cannot cover the breadth of the idea of sustainability. A single family home can be described as ‘energy efficient’ or ‘low energy’ but not ‘sustainable’’. I broadly agree with this, but I think that a single family dwelling can support ‘sustainability’ or ‘promote’ it but it cannot achieve it on its own.

Prof. Dr. Berndt Wegener from Humboldt University of Berlin, spoke about well-being from the perspective of a social scientist. He declared that the factors that lead to well-being can be measured,, but that they cannot be prescribed in advance. We cannot say that by doing ‘x’ we will definitely have ‘y’ benefits in terms of well-being. Pete Halshall, from the Good Homes Alliance, noted that feedback from residents shows that social tenants sometimes feel less ‘well-being’ than private tenants in the same building. There are other factors to well-being than those catered for by the built environment.

Stefan Haglind of Skanska wondered whether we should talk less about our impact on Nature, and more about Natures beneficial impact on us. If we understood better the effect on our sense of well-being and on our productivity of having better daylight, a nice view, comfortable temperatures and control over our environment, we would design better buildings and find it less difficult to have arguments about whether to adopt ‘green design’ or not. Studies, including the recent World Green Building Council report, show that there are considerable financial benefits to productivity from all of these features of well-designed green buildings that far outweigh the cost savings of lower energy use. I agree that we should emphasise the positive impacts of Nature, but I wouldn’t want to remove focus away from the catastrophic damage to our biodiversity.

Stefan pointed out that, for workplace productivity, the benefits from green buildings tend to be worth 100 times the value of energy savings. I wonder if there is a similar metric for the homes we live in? I can see a straightforward connection through home-working, our productivity at home is worth even more to an employer since the workplace is usually given for nothing. We can extend this benefit to the health service if we say that the home either promotes better health by being well-designed, or being sufficiently adaptable to enable residents to recover, or to be cared for, at home rather than requiring an expensive hospital bed.

Renata Hammer and Peter Holzer from Vienna provided some useful feedback from a small project where they had used the ActiveHouse tools for a small project with a private client. Their comments included:

-using primary energy as an indicator suggests that PV can compensate for other failings, and while this may be true for energy, it is not true for other environmental impacts. In this particular situation PV was inappropriate due to the heritage nature of the surroundings, and there was a lot of overshadowing, so in some situations this compensation is not even available.

-carrying out LifeCycle Assessments is a nightmarish process, and expensive in terms of the time taken to do so. (This was a recurring theme in the conference, with some speakers hoping that a production of many EPD’s over the next couple of years leading to a much easier set of data for designers and less technical people to use in their decision-making)

 

New Envelopes for Zero Energy Buildings

In a later session on ‘New Envelopers for Zero Energy Buildings’ there was a series of investigations into the LCA’s of different wall types. Erin Moore made some interesting points about the embodied energy of our buildings:

-that our current understanding of the relative amounts of embodied energy in our buildings is limited. Some studies put the amount of embodied energy as high as 50%, or as low as 10% of the total CO2 emissions of the building over its lifetime. She noted that the definition of ‘lifetime’ makes a big difference to the calculation, and that this figures varies widely around the world’.

-that the mitigation of emissions from embodied energy is more difficult than it appears. For example, can we claim that the embodied CO2 emissions from a home in the UK can be mitigated by putting PV on the roof? If the original emissions were from a country with a higher CO2 factor in the Grid, or if the original emissions were partially in China, how can we mitigate the damage in the UK? If some of the impacts are not CO2 related, but relate to a biodiversity loss, how can we deal with this where materials move from country to country?

 

 

 

Louis Kahn Exhibition at the Design Museum

Hurva Synagogue

Hurva Synagogue

The exhibition on Louis Kahn currently being held at the Design Museum, London, is worth seeing for all students of architecture, young and old. Kahn’s place in the panoply of modern architects is well deserved and this exhibition demonstrates why. Much of the material is familiar to anyone with an interest in his work, but the revelation for me is a series of large scale wood models of his work created by the Vitra Museum in 2012. These large-sale models, particularly of some of his unbuilt work, bring it to life in a new way. Models of the unbuilt section of the Salk Institute at La Jolla show the sophistication of that design in a way that drawings have never done, a design that presages the Government buildings at Dhaka many years later.

The full size model of the Fisher House window seat shows how Khan was able to manage the transition from the large scale down to the smallest scale in a way that few other architects have ever managed. This model illustrates a dwelling that was clearly humane and inhabitable in a way that few other architects have managed. Somehow Kahn was able to focus on the essentials of each of his projects without bringing his ego to the table. A quality sadly lacking in the work of many of our modern ‘starchitects’ who appear to be lauded for bringing their egos to the table to the exclusion of anything else.
Fisher House Window (Vitra Museum model)

Fisher House Window (Vitra Museum model)

Kahn’s particular philosophy , which can seem so obtruse and difficult at a casual reading, was sophisticated enough to guide him towards the creation of buildings places that are both humane and monumental. His buildings are effortless looking because he cared about the mechanics of construction and was prepared to use low or high tech materials where each was relevant. His interiors are beautiful because he cared deeply about how to illuminate them with daylight, the most precious commodity for an architect, and he wanted people to delight in occupying them and not just find them useful.
His design for the City Tower in Philadelphia, an unbuilt project, showed how radical he could be when he decided to expore structure. This tower, based on a space frame structure in the heady days of Buckminster Fuller, demonstrates that when architects follow an idea through to its logical conclusion it is possible to be both innovative and convincing. Fifty years later, nothing quite like this has been built.

Philadelphia City Tower (unbuilt) A three-dimensional space frame design that would be challenging to construct now, imagine how difficult this would have been in the 1950's.

Philadelphia City Tower (unbuilt) A three-dimensional space frame design that would be challenging to construct now, imagine how difficult this would have been in the 1950’s.

Finally, there is the Hurva Synagogue, and unbuilt project that demonstrates how he could take a design brief and extract a powerful, almost monumental building from it. It has more in common with Egyptian architecture from 3000BC than anything built since then. This apparently simple structure belies the sophistication of the ideas that have gone into it. Seeing it as a model brings home the power of the internal spaces and the imagined quality of the light that would have filtered through the gaps in this powerful structure. Like the Kimball Art Gallery he uses the structure to control the light into thin shafts that would have brought a magical quality to the interior spaces.

I continually find inspiration in Kahn’s work, go along to this and hopefully you will too.

Thermal Bridging – what’s the value of a y-value

Thermal bridging of construction elements has become a very important part of the compliance of housing in the UK, but you would never know this if you worked for a contractor, developer or architect designing, planning or building the said housing. Despite this being an important factor since 2010, the level of knowledge and understanding in the industry is still very low.

For new readers, thermal bridging is expressed as a ‘y-value’ or amount of heat loss stemming from the aggregated thermal bridges in a design. The thermal bridges occur at every junction in the building, every wall-to-wall connection, wall-to ground connection, wall-to-roof connection, all jambs, cills and heads, and all balconies, projections or bays. Each junction has its own ‘psi-value’ and these are aggregated together to make a ‘y-value’. In order to assess the performance of the building, all the junctions have to be measured and a value assigned to them.

This calculation is carried out using specialised software that calculates the rate of heat movement, or heat flux, through the junction.

To summarise the regulations, there are three options for compliance under UK regulations regarding thermal bridging.

  • take a default value
  • use accredited details or other approved calculations
  • use calculated details where individual junctions are calculated by a SAP or other qualified assessor

The impact of this can be easily illustrated. If we take a typical mid floor apartment, where there is a simple envelope, and two large openings in the façade, one for a bedroom and one for a living room. Where all else is unchanged, the difference between the default value and a calculated value based on accredited details is 0.5% saving of the DER, but when the lintels are changed to a thermally broken type, the saving increases to 3%. If this is the impact on a single mid floor apartment with a very simple envelope, the impact will be greater in a detached dwelling with many more openings.

This demonstrates that changing the manufacturer for a single junction can change the overall performance by 3%. This is the type of change that contractors are used to making on the fly as they make purchasing decisions about the project. They are not used to being tied to a more detailed performance specification that makes such a difference to the compliance of their project.

This lack of knowledge was typified on a project recently where the main contractor substituted one timber frame manufacturer for another, without checking whether the new manufacturer could match the thermal bridging characteristics of the original. The SAP Assessor had used the psi-values of the original manufacturer in the design stage SAP. The replacement manufacturer not meet the specification and they could not supply any information on the thermal bridging of their product at all. They had never been asked for it on previous projects.

This baffles me. Timber frame construction is a naturally thermally efficient construction method, for a company to sell such a system without providing calculated thermal bridging information is to hamstring their own performance for the sake of a few thousand pounds.

The companies who are paying attention to the changes in the regulations are taking the steps to have their psi-values of their products tested in typical constructions and they are using that information to make sales to contractors earlier in the process than usual, bringing themselves into the design conversation at an early stage of the project. By doing so they are getting themselves and their products written into the performance specification for the project. Whether it is thermally broken lintels, high performance windows, better performing insulants, or aerated blockwork, there are a lot of products on the market now which rely on this focus on thermal bridging.

The concern I have is that there is a lot of evidence in the industry that site teams and purchasing teams are not picking up on this need to watch the performance of the envelope, and they are substituting products to save money without paying attention to the psi-values of the materials they are buying. To be fair to them , the design teams need to be more explicit in the information that is provided to them so that it is more obvious to them what products need to be installed to be compliant. It is not reasonable to expect buyers to read through a SAP calculation, so a schedule of psi-values needs to be provided to them with an explanation as to how they were derived and why.

In the long run this focus on the fabric of dwellings can only be a good thing, as this is the best place to find savings in energy that are likely to be sustained in the long term life of the building.

 

Private Rental Sector – a Naturally Sustainable Approach

In a recent discussion with clients in the PRS sector a number of issues came up for discussion where the private rental market takes a different approach to the speculative housing market and the affordable housing market. These five issues are key to the success or failure of the private rental sector and at the same time seem to me to naturally point towards the design of more sustainable buildings than an equivalent project in the speculative or affordable housing sectors.

1. A PRS landlord is interested in the long term quality of the building: Private rental is a real market, if tenants don’t like it they can leave. Most modern tenancies are short and if the landlord treats people badly, or if a better offer shows up nearby, the tenant will leave. This ensures that PRS landlords will be kept on their toes for the duration of their ownership of the building. The building becomes a live asset, not a sunk cost. This will encourage landlords to maintain their buildings, keep their energy plant well maintained, and to ensure that services are running smoothly. Badly run buildings will lose their tenants more quickly than a well run one. PRS landlords will naturally tend towards better quality design that appeals to the current market. Low energy and high quality buildings will be more attractive to the market.

2. A PRS landlord is interested in the long term performance of the building: The success and failure of private rented buildings at a large scale, is maintaining a margin between operating costs and the rental income. If there is no margin, there is no business. This drives the design of private rented buildings to be efficient in their running and maintenance. The desire to cut out waste is essential to running any sustainable business, so the natural behaviour of PRS management will tend towards a more sustainable business model. The building will be designed to use space efficiently, and to be built with little or no waste.

3. A PRS landlord is interested in the comfort and wellbeing of the resident: Resident comfort and satisfaction will be more important to a PRS landlord than to any other landlord, as this is a key reason for people to stay or to leave. A building that is poorly designed or constructed will have less appeal to residents than a well designed and well constructed one. A building that overheats or is difficult to heat, or where residents can hear their neighbours conversations or music will have a quicker ‘churn’ of tenants. This is more likely to lead landlords who procure a PRS building to ensure that it is well-designed for the residents comfort in the long term.

4. A PRS landlord is interested in the lifecycle cost of the building: The operational cost of a PRS asset will as important to a landlord as its capital cost. In a speculative building the capital cost is everything as the speculative developer has no involvement in the long-term running of the building. This will naturally lead to a more sustainable decision-making process where a balanced discussion can be had as to whether it is better to build using better materials, (in the sense of durability, ease of maintenance,) or whether to use a cheaper material and have to replace it or repair it more often. In a speculative development something that looks good at the beginning is always favoured over something that costs more but will look good in the longer term. It is normal for a PRS client to consider the life-cycle cost of materials and services, and unheard of for a speculative developer to do so.

5. The PRS landlord cares about the long term usefulness and appeal of the building: A PRS landlord has a difficult task as a client to forecast what the market will be like in the future. Will tenants prefer more space, better light, faster broadband? What will future tenants crave that current tenants don’t care about. This means that the PRS landlord must naturally keep an eye on trends for the future rather than living off the trends from the past. A good example is car parking. A speculative developer will insist on including a lot of parking spaces as history says that parking spaces sell homes. In an urban environment this is increasingly not the case, and a PRS landlord will be aware of this and won’t want to take up more valuable space with cars than absolutely necessary.

It is interesting to me that all of these considerations apply to the affordable housing sector too, but because the affordable tenant doesn’t have much choice and rarely wants to leave, these considerations don’t apply as much as one might think. There is a shortage of affordable housing for rent, so the chances of a tenant leaving are less, and tenant concerns are less high up the list of priorities than they could be.

Similarly, the speculative housing sector is dominated by demand, so there is little competition in a specific areas and purchasers have few options. There is no need for speculative developers to consider these issues as the private sale market isn’t working in the interests of the purchaser.

It will be interesting to see how the housing supply chain in the UK rises to the challenge of the institutionally invested private rental building. The standards will be different, the approach will be different, and anyone who approaches it in the same way as a normal speculative housing project will be missing the point, and missing an opportunity to create a long-term, high quality sustainable asset.