| Boletín CF+S > 20 -- Vidas «tecnológicas». Ecos de Brasil... > http://habitat.aq.upm.es/boletin/n20/atwoo.html |
Edita: Instituto Juan de Herrera. Av. Juan de Herrera 4. 28040 MADRID. ESPAÑA. ISSN: 1578-097X
Tom Woolley[1]
Belfast (North Ireland), December 8th, 1998.
Synopsis of a Talk [pdf text, pdf slides]
I am a little bit nervous of repetition here. I am going to be
making some points that you may have already heard but I want to
try and reinforce some of them, particularly ones that Helmut was
making. I think it's important to consider what the real
implications are of the global issues we have been talking about
this morning. First of all there is the question of what actually
is sustainable or green. I think the word sustainability is in
danger of going the way of the word community, it can mean almost
anything to anybody. Also it's pretty well easy for anybody to say
something is sustainable today. I tend to call this "greenwash".
It's easy to make a claim of sustainability because no-one is very
clear what the definition actually is. There is also a fair amount
of propaganda about how we all need to do our bit, or a little bit.
I think that's not enough. We have to go a lot further than doing
a little bit. There are people who argue that doing a little bit
will make a significant difference, but because the subject of
sustainable construction is complex, simply doing a little bit
isn't enough.
I am going to say a little bit more about the waste of resources
and to go into the alternatives that are available. So
sustainability, I think, is becoming an overused word and it is in
danger of becoming a marketing device rather than a genuine
commitment. Just because you can come up with a product or a
solution which helps to save some energy and is financially viable,
it doesn't necessarily mean that it is going to save the planet.
The reality of sustainability is that most of the buildings which
we now produce with good levels of energy efficiency, achieve this
using fossil fuel based insulation products. These are fire
hazards, they give off toxic fumes, they can't biodegrade when they
are landfilled and they tend to pollute the atmosphere during
manufacture, and require a great deal of energy to produce them.
We rely far too much on glues, sealants, membranes and so on which
are synthetic, toxic, pollute the environment and often make
disassembly very difficult. So, many of the materials which are
used in construction are non-renewable, they leave holes in the
ground behind, and they cannot be easily recycled. This is the
reality, you just can't get away from this whatever we do. We
specify conventional buildings at the moment and we are consuming
resources. Even when we can include things like renewable energy
and so on, we are talking about a very long pay back period and
high environmental cost to achieve this.
We have already heard a bit from Helmut about the ecological
footprint of the kind of things that we are doing today. There are
different kinds of figures depending on the methodology. I have
used perhaps slightly exaggerated figures here, but they have been
put forward by people suggesting that we are in the developed
western countries using ten times our fair share of resources and
we will be needing somewhere between 6-10 planets to sustain our
current use of resources. The construction industry is a
particularly big consumer of resources in terms of energy and one
of the main contributors to carbon emissions. We waste a
tremendous amount of material which goes onto building sites, and
I am constantly amazed, even in this day and age. Construction
waste is also one of the biggest contributors to landfill which in
itself is an environmental problem. We also have a huge number of
empty, disused or underused buildings which could meet many of our
needs and yet we are under tremendous pressure to build new
buildings. As we have heard there is a tremendous need for housing
to meet the needs of people. So I think if you look at this from
a global perspective the present practice is not sustainable, it's
not acceptable.
One of the things that tends to happen in this discussion about
sustainable development and green building and so on, is that we
tend to talk largely about new build demonstration projects, but we
are talking here about a very small percentage of the stock. The
real problem, the real issue, is what to do with existing buildings
and how to make them less damaging to the environment and there is
surprisingly little work being done on that. I have tended to be
focussed on looking at new build possibilities and suddenly
realised that in fact this is not actually the major problem. It's
what we do with out existing buildings that's the most important
thing. Re-using existing buildings and therefore saving the
embodied energy which is bound up within those buildings and
reducing the amount the demolition waste and so on is incredibly
important. So this is something that we really need to focus on
much more in the future.
We also need to think a bit more clearly about the whole business
of energy. I have been at a number of conferences and events where
people have attacked me for focussing largely on materials and so
on because they say that energy in use is the most important thing.
We don't need to worry so much about how we do it, it doesn't
matter if we use toxic and energy expensive materials, because if
we save energy in use then that's the most important thing and
figures are produced to justify that argument. But if you can
actually produce a carbon neutral project, which as Bill Dunster
has shown, can be quite achievable, then the actual nature of the
materials and the resources bound up in production become much more
significant. So in many sectors, particularly office and
commercial and so on, buildings are being changed all the time so
that over the life of that building the amount of resources and
energy that goes into conversions and alterations becomes much more
significant. It is terribly important, in my view, to consider the
environmental impact of the materials and resources that are used.
It is possible to reduce is in a number of ways. We also need to
think very seriously about what happens to those materials when
they come to the end of the line, so that they can be dismantled or
reused. Even if they are stripped out after a short period of
time, which very often happens in buildings, that they can be
reused so that we are all the time looking at how to save
resources.
One of the difficulties that we have is that there are now a
growing number of demonstration projects which are very much seen
as exemplars of the way forward. I find that many of these
projects are what I call `off-message'. In other words they are
not necessarily giving people the right signals about the future.
In a way it is a bit unfair to attack particular projects and I
accept that there are worthy intentions. Nevertheless, we have
been doing research by looking at about 200 projects which are
promoted and claim to be sustainable, green, environmentally
friendly, ecological or whatever. We try to work out what's gone
into those projects and how far they actually come up to the claims
which they are making. This is one particular example which is
fairly close to home which is the Ecos Centre. Even though it is
an incredibly important demonstration of renewable energy, there is
virtually no use of
passive solar energy within the design of the building. A lot of
concrete and heavy materials are used in the construction of the
building and this is justified on the basis that thermal mass was
required. But because there is no use of passive solar I find it
hard to understand what the thermal mass is supposed to be doing!
This is a building which is purely there to demonstrate the use of
renewable energy, but they still only meet 75% - 80% of their
energy needs from renewable energy. The building's not well
located. You have got to drive to it. There's also no involvement
from the local community in a local housing estate. I think these
buildings are giving the wrong messages.
Another building that I am critical of is the Gaia Energy Centre at
Delabole. It is one of the first wind farms in the UK. Here we
have a building being made out of concrete blocks, aluminium roof
and cedar cladding, and it is described as using sustainable
materials. I don't understand how that kind of claim can be made.
It has this very beautiful steel and glass water wheel. As there
is no water driving it the water is pumped up and then spins the
wheel around. I don't understand what that is demonstrating and
there is virtually no use of renewable materials. When I
challenged them about this they said they would like to have done
all those things but we couldn't afford it.
We have got to get these things right if we are going to teach
people what needs to be done in the future. We need to adopt an
holistic approach in which we look at the upstream and the
downstream impacts of everything that we do. There is no magic to
this. You could come along and pay us a lot of money at the
University to calculate lots of things like embodied energy, and do
lots of lifecycle analyses and there's all sorts of stuff that can
be done on that. But in a way the basic principles are very simple
and if people were to follow those in a very practical and down to
earth way you wouldn't necessarily need to do a lot of
calculations. It's a question of thinking through the impacts of
the decisions that you are making.
Beyond carbon neutral buildings we have to look at zero impact,
because if we are consuming more resources than we can sustain over
the next decades then we have to look at different ways of doing
things. The figures that Helmut showed demonstrated this very
clearly. Now, it's not necessarily going to be that easy to
achieve zero impact buildings. But at least if we set that as a
benchmark, as a target, something we are trying to work towards,
then we can have some kind of basis on which to judge how far we
are able to achieve hat aim.
All buildings inevitably are going to use some resources. Do we
have to use as much as we normally do and are there other
alternatives? Many of the assessment systems currently available
to us to evaluate projects - SAP was mentioned just a few minutes
ago - are essentially based on existing practice. They are trying
to push things a little bit further along, but are not based on a
fundamental critique of the way we do things now.
So what sort of things do we need to move towards zero impact
building? We can use renewable materials. Renewable means
renewable! In other words that those materials can be replaced
within a realistic timescale. The big issue here is about timber.
For instance, the Gaia Energy Centre say that they use sustainable
timber, but what does that mean? If you cut a tree down, it's
going to take 60/70 years for another tree to grow. You can't get
away from that, you can't just get trees to suddenly pop up. If we
carry on chopping down the forest at the rate that we do, we are
going to have serious problems because we are going to have to wait
60/70 years to replace them, even if their supposedly being managed
in an environmentally friendly way. At least with the Forest
Stewardship Council (FSC) we have got some kind of benchmark of
good practice but those sort of methods are not available for other
materials.
Materials have got to be responsibly sourced. It doesn't mean
getting it from the other side of the World! I was talking to
people at the trade exhibition at the RDS in Dublin who are selling
granite products, and they are doing extremely well. There is a
big upsurge in interest in granite particularly from the public
sector replacing kerb stones and the nice urban upgrading schemes.
The granite is coming from China. Now using recycled materials is
an obvious thing to do but we have to be careful about that because
that can then feed the demolition of existing buildings in order to
generate high quality architectural salvage when those buildings
perhaps themselves ought to be retained and used. So we have to be
very careful. We obviously have to try and create a carbon neutral
building, reducing energy as much as possible, so we have to
introduce some kinds of controls. These things have got to be
thought through and talked about and they are not being talked
about rigorously enough at the moment.
There are a range of possible materials which can be used which I
would characterise as low impact materials, not necessarily zero
impact materials. For instance earth. We can use clay and mud
forms of construction. This can replace a lot of the materials
which we currently use from quarried and highly processed
production processes. But earth is not a renewable material, once
you have dug it up out of the ground it isn't going to reinvent
itself. It is going to go into your building. Potentially in
small scale developments you can maybe use the earth that's
underneath the building, you need to dig it up anyway. So earth is
only a low impact material, it is not a zero impact material. On
the other hand it has a tremendous potential as a building material
and should be considered at all possible times when you are looking
for an alternative.
Then there are an awful lot of materials that are made from waste
materials such as fly ash. Glass is a potential material which, if
recycled, can be used for building products. The levels of
technological development in this area is varied. It is possible
now to replace cement. There is a lot of work going on around the
World using rice husk ash for instance to replace cement and
produce very good quality materials. So there are potentially
renewable resources. There are waste products, but sometimes these
are relying on power stations and other things that in a sense we
should be trying to phase out anyway.
Then there is quite a lot of very interesting work going on using
bio-composites and eco- composites. One of the crazy things that
tends to happen these days is that there is a huge gap between the
scientific community and the construction industry. There is a
great deal of innovation and people are working on remarkably
interesting new materials, but nobody from the construction
industry is ever at the conferences. There's no interface, there's
no technology transfer between the innovation which is going on and
the possible uses of these materials. So there's lots of patents
building up in filing cabinets, but nobody's making any use of
them.
Recycled materials, I have mentioned, cannot really be seen as a
zero impact material. We've been doing research to look at
materials that are genuinely renewable. Particularly we have been
doing research into the use of hemp as a building material. We
have been looking at straw bale building. It's still regarded as
a bit of a joke in the UK but straw bale building has become so
mainstream in the USA. I was invited to somebody's house in
California which turned out to be a straw bale house! They hadn't
even though to mention it because it wasn't seen as anything
particularly unusual.
Timber again is a renewable material, but we do have to be
conscious of our responsibilities in this respect and obviously we
can use recycled material as we saw in Bill Dunster's presentation.
But a lot of timber is being imported from the other side of the
World and there are quite major attempts to undermine for instance
the Forest Stewardship Council certification methods. People are
challenging these things in order to allow more unsustainable
timber onto the market.
Products like wool, you know the farmers had tremendous problems
with what to do with all their sheep. Wool could be used as an
insulation material and there are a number of company's developing
that now.
Bamboo is perhaps the most renewable material that you could
possibly. It can grow so quickly that you can actually watch it
growing! So if you cut down bamboo plantations it can regenerate
itself within 2 to 3 years. There's some remarkably interesting
exciting buildings and building products using bamboo. Bamboo can
be grown in temperate climates as well; it doesn't just have to be
seen as a tropical material.
We are currently working on a project called The Grow Build Project
and the idea is to see whether it is possible to grow your
building. This is not meant to be seen as some kind of peripheral
project, but it's to be something that could be part of mainstream
construction. There is no reason why the kind of experiments we
have been doing couldn't be duplicated on a much larger basis, and
we have been very excited about the possibilities.
We are using composite mixes of hemp and lime, and also hemp and
earth. There is a conventional form of hemp construction in France
which used quite high amounts of hydraulic lime. We are trying to
replace this with earth and ending up with something similar to the
old-fashioned cob building. We are trying to develop it in a way
that can be very sophisticated, delivered to site in a way that can
be quickly and easily used. It is providing a material that has
very, very low impact indeed, and it has all sorts of other
environmental qualities. Apart from that it also provides an
alternative crop for the rural economy and its adding a great deal
of value to something that otherwise is currently just being sold
as horse bedding.
Up to now most of the work that has been done on this hemp project
has been funded out of my own pocket with a little bit of help from
the University and a tiny grant from the Millennium Commission. It
is surprisingly difficult to get funding to develop these sorts of
innovative approaches.
One of the important things which always worth looking at if you
suspect there's some "greenwash" going on, or if people are fudging
their commitment to sustainability, is to look at the issue of
indoor air quality and the health impacts of buildings on people.
This is an issue which is very, very frequently ignored,
particularly in the UK. It seems to have a much higher profile in
the United States and Germany and Holland. But here somehow we
seem to have put up with all sorts of vile pollutants into our
buildings and breath them in happily without being concerned about
it. I am completely at a loss to understand why that is the case,
but it does get overlooked time and time again. We have looked
through a couple of hundred examples now, so called green and
sustainable demonstration projects in the UK and hardly any of them
concern themselves with indoor air quality and with the health
impacts of the materials. There are toxic materials used within
those buildings. It just isn't on the agenda here. Attitudes are
changing. We did a programme on Radio 4's Costing the Earth about
this. There was a huge response from the general public who are
interested and concerned, but simply can't get the information
about it.
We are also working on a research project funded by the EPSRC into
the opportunities and obstacles for green materials and products.
I like to use the term green because I think it's a bit less
equivocal than sustainable. We are working here with relatively
small companies. At least one of them is represented here today in
the shape of Natural Building Technologies who are trying, and
having some success now, of getting green and sustainable products
and materials into the mainstream, onto the shelves of builders
merchants and taken up by fairly major projects. But it is quite
an uphill struggle for these companies and they are constantly
having to fight. It's a very much David and Goliath fight.
One of the other companies, Eco Solutions, produces an
environmentally friendly paint stripper, has constantly to fight
against propaganda from the big multi national companies that claim
that they've got products that do the same thing. It's not easy,
and the amount of support that comes from Government for this is
extremely limited. We are beginning to document cases that we come
across where people claim to be using sustainable materials but
when it comes to it on the site, these products are substituted by
conventional materials.
There's always the big excuse about how it's going to cost more.
But it doesn't have to cost more if these things are designed and
specified in right from the start and the thing is thought through
properly. There is absolutely no reason why there should be extra
cost. OK some materials do on the face of it appear to cost more.
But those costs are going to come down as there is a much bigger
take up.
If local authorities, for instance, were to really seriously
implement green purchasing policies, particularly in the
construction sector, even just local authorities represented in
this room, that would create a much, much bigger market for the
kinds of environmental products which are now becoming available.
If they were taken up on a large scale then you would find the cost
would come down significantly. In theory, many renewable products
would cost much less than the expensive fossil fuel based synthetic
quarry products.
There are obviously problems of a lack of availability and ways to
get hold of these things. Very often there is ignorance, people
don't know they're available. Then there is virtually no Government
support at all, there are no programmes targeted on supporting
development of sustainable construction. Even the EPSRC programme
that we are funded under currently appears to have disappeared
because of a lack of bids from the University sector for research
into sustainable construction.
I am trying to challenge you to think that it's not easy. We have
to make radical change in the way we build our buildings and what
we use to make them if we are really going to start to reduce
resource use and materials.
Fecha de referencia: 16-07-2002
| Boletín CF+S > 20 -- Vidas «tecnológicas». Ecos de Brasil... > http://habitat.aq.upm.es/boletin/n20/atwoo.html |
Edita: Instituto Juan de Herrera. Av. Juan de Herrera 4. 28040 MADRID. ESPAÑA. ISSN: 1578-097X
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