A short talk to the Calder Valley Community Land Trust on the 22nd August 2018
"I have a little to add to the presentations by Duncan Roberts[1] and Marianne Heaslip[2].
I started work as a building services engineer, the job of
making sure the heating, ventilation, lighting and plumbing work. These are
essential elements for creating sustainable buildings and have been involved in
low energy projects, modelling and measuring for some years.
I would like to introduce 3 ideas that I think helps keep
sustainability on the project agenda.
Avoiding sustainability slip,
The value of measurement,
1.
Avoid Sustainability Slip
David and Marianne have shown us a number of delightful and
sustainable buildings that may look familiar as buildings and as homes. We must
not forget that they are possibly more complex than their looks show.
The design process itself is a complex production involving
a cast of thousands. There are funders, client bodies, potential users,
architects and numerous engineers and specialist consultants, Quantity
Surveyors, planners, builders and sub contractors.
All of these may be concerned with sustainability, but they
all have their jobs to do, which will keep them busy enough.
The out come can be what Arup, engineers and
sustainability pioneers, called “sustainability creep” and I prefer to call “Sustainability
Slip”,
Each player in the process sees new limitations or
constraints that undermine the original aspirations.
The client will ask for an award winning exemplar building
and even be willing to pay a substantially over the odds for this. One example
of this could be the delivery of the PassivHaus energy standard building.
The architect may feel the extra budget can justify higher
quality products, even if they have little environmental advantage. and leaves
it to the engineers to design the foundations to both hold the building up and
keep the heat in.)
The cost planners or quantity surveyor will suggest cheaper
options, although they may have greater environmental impact. They may decide
not to employ a registered PH consultant and leave all that to the engineers.
There is a whole specialisation of ‘value engineering’.
Where designs are optimised for cost, ease and speed of construction, but not
necessarily whole life impact. The expensive foam glass insulating supports for
the foundations will be replaced by insulating concrete blocks.
The contractor may suggest methods and materials that will
save time (and of course money) but may not perform as well as the original
sustainable concepts. They may decide to use cheaper blocks in the foundations.
The sub-contractos, who in fairness may not seen the whole
concept for the building, may not be familiar with novel methods of
construction eg the high levels of insulation or effective air barriers. They
may say “We have always used solid concrete blocks to support the timber frame”.
That is why Marianne has to visit site every week.
And so on. Commissioning tests may be poorly documented,
handover hurried, operating manuals cursory, defects poorly remedied and
“practical completion”, when the final bills should be paid, a bit too final,
leaving the users with a building they do not understand.
I have seen several projects where proposed exemplar
buildings end up hardly improving on the average building performance.
What we have learned, is that to prevent slip,
sustainability needs a project Champion. Someone clearly identified as a member
of the design team with that specific responsibility.
This is not a prescriptive task, not a role of policing
standards, but one of listening and problem solving, helping the different
players in the project find the creative solutions to the problems, the contradictions
and the conflicts that make up a complex project.
Experience has shown that the social and interpersonal
aspects of the task outweigh the technical competance. Our champion will need
to be someone with communications skills more than knowledge the technical
aspects.
2.
“One measurement is worth a thousand expert
opinions.”
My second point is to reinforce Marianne’s discussion on
monitoring.
As an engineer it is easy to become obsessed with the
numbers, but we must not forget them. One of my first acquisitions after
graduating was an engineering data book, with tables of diameters of imperial
nuts and bolts and their metric equivalents and the number of threads per inch.
On the front was written “One accurate measurement is worth a thousand expert
opinions.”
Actually I have grown to like this even more when I found
its attribution. Grace Hopper was one of a
few notable
women engineers in the first half of the last century, an admiral in the US
navy, and more famous for coining the work ‘bug’ as the explanation for the
problems with early electronic computers.
The language of architecture, environmental engineering and
sustainability are hedged about with qualatative words and concepts, “Delight”,
“healthy living”, “comfort”, “air quality”. We must not forget that these are
all based in reality.
I am an enthusiast for standards and see modelling as a key
ingredient of measurement.
PassivHaus comes with a measurement tool, the PassivHausPlanningPackage (The PHPP). Before we start designing a building, we define the energy criteria
to be met, and as we design it, we can not say that is a bit hard, we will
allow a bit of leeway there. We take the finished design and check it in the
PHPP and confirm that it meets the criteria.
The PH assessor will then follow the construction and ensure
it is built as designed, changes are evaluated and it is tested properly.
I have spent my career concerned with commissioning tests.
In the early days, it was the challenge of my own designs. I had put the red
arrows on the drawings, saying that is where the warm air would go.
But before completion we have to go back and measure the
flow and temperature and deal with the measured truth. Is it the design, the
equipment, the installation. Can we work with the subcontractor to sort it out
while the client is in a hurry to take over the building.
Hopefully the increasing requirement for Post Occupancy Evaluation[3] or the SoftLandings framework for design
management will reduce the problem. SoftLandings is a new addition to the
design and construction process, that encourages clients and designers to
consider the handover and use issues from the beginning of the project and
imposes a 2 year follow up period after handover, not just the 6 months defects
liability period.
3.
Occupant Behaviour
Some time back in the 70’s I went to a talk by Eric Claxton[4], the traffic engineer for
Stevenage New
Town in 1946. He explained that he had created a new standard for bus laybies for the road network, longer than the normal ones. It gave the drivers more room to pull completely of the road. Less work to keep the traffic flowing. He said it was “Making it easy to be a good citizen”
Town in 1946. He explained that he had created a new standard for bus laybies for the road network, longer than the normal ones. It gave the drivers more room to pull completely of the road. Less work to keep the traffic flowing. He said it was “Making it easy to be a good citizen”
While I agree with Marianne’s point about building homes as
‘dumb’ boxes, which of course reflects the Calder Valley Community Land Trust
Sustainability Policy, proposing the “ ‘fabric first’ approach to
energy-efficient design”.
But we must not forget that houses are engineered
constructions with a few quite sophisticated components. I think there are four
issues to remember.
i) New built homes may not be the same as the ones we
learned to live in. Just because I took my driving test in my 1960’s Morris
1000, does not mean I still have to use the manual choke to start, to double
de-clutch in to first or even wave my hand out the window to indicate that I am
turning left.
Occupants of well insulated, air tight houses need to re
learn some of the building behaviours. When we built my first highly insulated
low energy student rooms for the University of East Anglia, it took a long time
for students to learn that drying their football socks on open windows while
they were out would cool the room down and it would take several hours to warm
up again, while the shower room with its extract fan would do the job as
quickly.
But new owners and tenants have a lot on their mind, and
drying socks is not near the top. Handover is not the best time to tell them
about the intricacies of their heating (especially if it has been like the last
few months.) The project must allow (and budget for) the production of clear
instructions and follow up visits from the sales or housing team to answer
their questions.
ii) There are some appliances that are obviously state of
the art. The condensing boiler, the heat recovery system. Not to forget that to
continue to work effectively and efficiently, they will need maintenance.
Again, it should be in a manual and it should be explained, at the right time,
to the occupant. My first employers, Fulcrum Engineering, used to put a years
maintenance and the first service in to the plumbing contract, although often
the QS would take it out again. SoftLandings suggests a two year follow up
process.
iii) As designers familiar with building systems, we must
not assume that our clients and users are. We all have different cultures and
use different metaphors. Does that red light mean that the boiler is on or that
there is a problem? Why do we assume that a squiggly line on a warning light
represents an air filter. Who has seen the symbol before or even an air filter
itself.
iv) I am no enthusiast for automatic controls. We know we
should turn off the lights when we leave a room and motion sensors could ensure
this happens. But some lights do more that provide illumination. The hall light
may be a welcoming sign or a living room light may reinforce the feelings of
comfort, and a light switch in the right place the best option.
On the other hand, it may not be obvious who should switch
off the lights in a common staircase, so automation may be the best answer,
So, whether lighting controls or boiler thermostats, the
function must be obvious, they must be easy to override and it must be clear
how to deal with faults.
4.
Conclusion
If our buildings and homes are to be truly sustainable, the
process of designing and building them must take it seriously and
sustainability must be kept “Front of mind” though the project. They must be
build to be used sustainably, which means seeing the project as concerning the
whole of the life of the building. Who is living there, how will it be
maintained, what will happen as it matures and changes."
[1]
Duncan Roberts from Tyneside, is an architect has taught at the Centre for
Alternative Technology, in Machynlleth,
[2]
Marianne Heaslip is an architect with the URBED Co-op in Manchester and a Sheffield
and CAT graduate
[4]
Eric Claxton (1909-1993) O.B.E, B Sc., C.Eng, F.I.C. founder of Casualties
Union 1942, chief engineer Stevenage Borough Council 1962 -1972
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