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If we asked several construction professionals to explain the meaning of “sustainability” we will get several different answers. That is not to say that there are broadly differing views. It’s just that sustainability has different values across the construction lifecycle. Take for example the financial issues of running a contracting or supply business; to remain sustainable in today’s markets, companies have had to cut costs and reduce workforce in order to be sustainable.
There is no doubt that the word is overused and misunderstood in many areas of the market, which is shame because there are a few companies who are really making headway in the challenge to our society of making construction more sustainable.
In fact what we should be discussing is sustainable development – a term which was coined by the Brundtland Commission in 1983. They described sustainable development as development that “meets the needs of the present without compromising the ability of future generations to meet their own needs." In this context we can look at construction in carbon costs, material sustainability, lifetime maintenance in carbon costs, social sustainability, running energy requirements in carbon costs and of course recyclability and/or refurbishment at end of use. We should also consider, taking all the above into consideration, financial sustainability of the whole process. Now we can see why we have differing opinions depending in what area of the construction process we are sitting.
Social sustainability? Looking at some of the blunders of the past when we envisaged that we were all going to live in high rise tower blocks in the 60’s, we now know the social problems that occurred and are still with us. We need to develop sustainable communities, places where we want to live and socialise.
Only by bringing all these aspects together can we truly bring about sustainable development now and for our future generations. The subject is huge and we need to have better joined up thinking across these topics in the future – we are getting there but it is a very slow process.
In the UK we have tried to adopt some of the European thinking on low energy developments. We have looked at the Passivhaus construction methods which insulate a property to such a high extent that a central heating source can be left out with energy to heat the building coming from passive solar gain and the occupants (we actually give off on average, 100 watts of heat from our bodies). While we can admire the thinking behind this, these developments have been designed for climates where in some cases temperatures fall below -10° Celsius for several days or weeks per year. In the UK and Ireland we are in a much different climate and adopt a different lifestyle in our properties, both for work and living spaces. We also have a varied climate across the UK. For example a property in Portsmouth will have different requirements to that of a property in Birmingham or Edinburgh. What we need to do is develop a style and construction of property which suits our way of life and the climate we live in.
For up to six months of the year in the UK, again depending on North/South location we switch off our heating systems and now often adopt a more outdoor way of life. Look at the huge increase in sliding folding door sales in the UK. With increasing temperatures our homes are changing. Whilst the thinking behind Passivhaus is to be commended, it’s clearly not for the UK.
We have some very switched on architects in the UK. Look at any of the building magazines where UK architects are world renowned and very much sought after. The same can be said for sustainable development which is beginning to take to the stage. One such design development that Senior Architectural Systems are actively supporting is the “BaleHaus” scheme which was developed by Craig White of White Design based in Bristol. White Design has set up a company by the name of ModCell to develop the method of construction, more of which can be seen at http://www.modcell.co.uk/
You may have seen the “Grand Designs” TV programme last year which showed a timber-framed building with walls constructed out of rendered straw. So why straw? Taking a storey height timber-frame and packing it with suitable straw and then offering a lime render to both sides creates a watertight but air permeable panel with U values as low as 0.13. By using straw we create a carbon bank – taking carbon out of atmosphere as it grows and locking it into a building material. But the process goes even further.
“Triple Sustainability”, the ModCell process, uses a flying factory where the construction of the panels takes place locally to the project where the straw is grown, keeping carbon costs to a minimum in transportation. Secondly the process uses local farm hands to manufacture – social sustainability. Finally by utilising the many barns across the UK countryside in which to manufacture, we improve economic sustainability.
The process loosely follows the Hybrid timber aluminium range of doors windows and curtain wall systems, designed by Senior Architectural Systems. Rather than product being manufactured abroad, Hybrid products are made locally across a wide network of fabricators, often local to a project. This process both reduces carbon emissions in transportation and offers much quicker lead times from agreed dimensions or site measure.
The BaleHaus project is now taking shape at Bath University where the construction is being very carefully monitored and once constructed, the efficiency of the construction can be accurately established. The project is being fitted with Hybrid products supplied by Senior Architectural Systems.
So what about triple glazed windows and fixed lights required in order to meet high insulation requirements? Possibly not the option we need in the UK. As mentioned earlier we like to open up our homes during the summer lighter months when the need for heating is all but eliminated. In winter we need the insulation but still want to gather passive solar heating and taking a simple Edwardian building design for example, where internal shutters were closed on darker evenings to provide insulation and security, we may have the answer.
What we may end up with is high performance double glazing, possibly in the form of vacuum sealed units, using various opening lights and systems offering large areas of glazing, with external shading in the form of insulated shutters which can be used for solar shading as well as night time insulation. What is certain is that we live in a quickly changing world and fenestration product development is going to be very interesting for all of us. At Senior Architectural Systems we are already looking at future construction developments and working with several centres of excellence to determine the future needs of the industry and our customers.
Lennart Jonsson is Managing Director at Senior Aluminium Systems Limited
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Plan Magazine
