Building a sustainable design specification pt. 2

  • Building Design Expert
  • 5 years ago

Specifying for a Sustainable Future pt.2

See specifying for a sustainable future pt.1

How strange, you might think, to see one of the most expensive metals on this planet appear on a list of ‘sustainable’ products. On the face of it I agree, until you look at its credentials which have stamped Lead’s passport to the world of greater sustainability. Note the use of terms like ‘greater’, or ‘more’ sustainable. I have said it previous blog posts, but make no apology for saying it again that true sustainability can only be found next to that crock of gold at the end of the rainbow. We can get closer and closer, but it’s always just beyond finger-tip reach.
On that basis Lead has no chance of being measured as sustainable; after all it is a finite resource. It’s this perspective that seems to become skewed when the industry, and indeed governments, refer to design and construction being sustainable. How can it be?
Apart from the direct heat and light we contrive from the sun; All, and I mean ALL of our resources come out of the ground, there are no exceptions. Just to remind ourselves of the theoretical definition arrived at in part 1 of this blog:

Sustainable Design uses technology and materials that are replaceable through natural process at a rate equal to, or greater than their consumption”.

In other words, anything taken from the ground that we cannot put back is a finite resource, and there will come a day when we will not be able to take it out of the ground any more!

Our efforts to quarry and extract those finite resources have historically left a scarred and disfigured landscape. Recent European law and improved practices amongst some of the larger mining companies have led the restoration of the scarring, but it goes without saying that the landscape has changed forever:
  • Clay
  • Stone
  • Slate
  • Metallic ores and other minerals
  • Water
  • Fossil fuels
Not an exhaustive list, but enough to make the point. Think about it for too long and the prospect of running out of any of these becomes part of your worst nightmare. Even then I don’t think it will be that good.

Remedies?

Quarry

ALL of our resources come out of the ground, there are no exceptions

No. There are no remedies. There is no magic bullet. All we can hope to do is be frugal with what we have. Then to realise that, we have to eradicate selfishness. Perhaps we haven’t time for that long game either? But at least the construction industry could set an example. Look around us and what we are doing, except we need even more focus from that realisation.

Water
The long hot summer of 1976 was memorable for water supply mains being turned off for large parts of each day. There were stand pipes in the streets of some neighbourhoods, and reservoirs looked for all the world to be part of some desertscape. At that time the UK population numbered around 56 million. By 2011 the population had increased by some 6.5 million, but we have no more water than we did in 1976, just the 6.5 million more mouths to fill. Okay, it’s not quite as stark as that, because we have had large improvements in infrastructure that have offset the increase. But we can steer around complacency when we know the offset equates to a bullet point on a sheet of AO paper. Just as an underline, we are projected to be sharing the same amount of water still with another 14 million mouths by 2030.
We want to use more water than there is, in a country that has plenty of rainfall; so clearly water is not replaceable through natural process at a rate equal to, or greater than its consumption, and is therefore not sustainable.

Recycling
Thank goodness for technology. But there is a down side to technology, as it invariably uses other resources and energy. There is no doubt that we must seek ways to recycle water – ‘Rain water’ and ‘Grey water’. The pumps required in the collection chambers could be powered by photovoltaic cells. But PV panels are currently full of heavy metal pollutants, so what happens when they reach the end of their useful lives? Expensive, specialist recycling of those toxic materials. The trade off being the enjoyment of ‘free’ electricity in the interim.
So here I bring back the working definition from part 1 of this blog:
“To remain practical we may often be required to make a ‘Best Fit’ with available and affordable technology, resources and materials”
So here the best fit is the trade off with having a cheaper, and more plentiful water supply, set against the perceived downside of disposing of the responsible technology when it no longer adequately performs its function. Nuclear power is analogous in this regard, and how many heads do those two words turn?

A maintenance free building life cycle
I have also discussed these issues before: Buildings do not have a design life, and nothing is maintenance free. Remember it is not the buildings, only their components that wear out. They do so at different rates which contribute to a maintenance cycle. It is the maintenance cycle we need to focus upon. Whilst we cannot be ‘maintenance free’, we should look to prioritise low and effective maintenance.
If components have to be replaced, that will inevitably consume more of our finite resources as part of the manufacturing process. So more maintenance will generally work against greater sustainability. If we can reduce maintenance down to simple cleaning, that may begin to win the war, as opposed to the odd battle.

FREE is good
Most people like ‘free’; it just sits easily in the corner and gets on with things. Renewable energy technology is definitely not free. It’s getting cheaper, but it’s still largely an elite option, and needs to become more affordable still. The fuel? The sun, the wind, the rain and geo-thermal energy; now they are free. If we can therefore deal with the capex on the technology, the rest should be plain sailing; as long as we remember that application of the appropriate technology is a key issue. Wind turbines and suburbia are generally not good bed partners, notwithstanding the fact that such a combination may receive full credit under some well known sustainability assessment criteria; we must be so careful not to ‘box tick’.

Green ≠ Sustainable
No apologies for citing this one again. PVCU window and door frames are ‘green’. A well designed profile can help reduce cold bridging and save energy. But this material has a petro-chemical base – a finite resource. This is a good example of the ‘Best Fit’ odyssey: Does the energy saving potential coupled with the reduced maintenance of the material totally mitigate the embodied energy within the product?

Criteria that affect the sustainability level of our specification
Building design professionals are faced, every day, with a potential dilemma involving choice of materials and construction methods that will fulfil their architectural aspirations. Those experienced in the process have generally developed a ‘best fit’ auto-pilot that navigates them through the various stages of design and materials selection. Taking a glance over our shoulders at our most recent projects flown on auto-pilot, there may well have been some significant room for manoeuvre, in improving  any nod towards project sustainability. Largely it will require a sea change in our mind sets to consider our best overall compromise with:
Material –
  • Performance
  • Appearance
  • Longevity / Maintenance
  • Cost
These in addition to our principles, or perhaps all of the above, and only the best fit compromise will square this circle.

Priorities
It would be impossible to draw up a definitive list of the world’s finite resources in order of their abundance and contribution to ‘sustainability’, because as we know – each project has different intrinsic requirements for its need and purpose, and it’s impact upon the environment is never truly predictable. However, at the top of any such mythical list would always be ‘energy’. Our reliance on fossil fuels to manufacture ‘energy’ in the form we need it is unsurpassed by any other natural resource. The simplistic resolution therefore is that we should prioritise the conservation of that least remaining. ‘Energy’ must be found in other forms, or we must super insulate our buildings to use less. Consider the ‘best fit’ insulation specification: There is no doubt that petro-chemical by-products produce the highest performing materials, and insulation is no exception. So do you conserve more energy by using a higher performing insulant that in itself is helping to diminish the same parent resource. My answer: Most definitely yes. For example if insulation space is at a premium and the best results (most energy saved) will be realised from a petro-chemical based product – decision made!
We can best achieve our goals by the implementation of a little pragmatism:
  • Client brief – Of course we must meet a client’s requirements for end of project performance. But how we meet it is often up to us as construction / design professionals – exercise your knowledge, experience and influence.
  • Alternatives – There is seldom only one way to skin a cat. Take the time to consider all the available options – Get out of that box and think.
  • Waste awareness – BIM will encourage this more and more. The trick is to use your supply chain to value-engineer the project at the beginning, not at the end.
  • Recycle – If you can engineer a way to use the bricks from the demolition site down the road, rather than buy them new, then that needs some serious thought.
  • High Performance / Low Maintenance – Source the highest performing materials, or products, with the most sustainable credentials, and the lowest maintenance requirements on a project specific basis.
99% of the time we cannot provide all things to all men; all these things collude to provide a best fit compromise.

Conclusion
Any conclusion on this subject is likely to be half the story in reality. It remains the experienced individuals responsibility to assess the potential of any construction operation on a project by project basis. It would be impossible to put forward a formula that was all things top all men, and cover all bases.
As long as we remember that out of the ground we continue to extract irreplaceable minerals, fuel and water, and construction industry professionals are uniquely placed to switch from auto pilot to manual, and take control our destiny. It really is that simple and that serious, and building a sustainable design specification will play a huge role.

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