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John Davies v2

By John Davies, Head of Sustainability at Derwent London plc

Have you ever been in that situation when what you ordered something from a catalogue that looks completely different to what’s in front of you?  Or felt that sinking feeling when something doesn’t live up to expectation?  Chances are you probably have – that’s life!

And it’s the same kind of feeling I get when I sit down with my Energy Manager and review operational data performance and then look at the original energy design calculations – one says it’s great by bettering the notional building by X% and the other…well the other says something quite different.

Whilst those in industry know this scenario all too well, you might be surprised (or not) to know that it still does catch a lot of folk unawares, and in doing so provoke a reaction along the lines of “well that’s just stupid….what do you mean it doesn’t take into account computers, there are going to be hundreds of them; no lifts, but are going to have 8!?”  Ever heard that?  I’ve now lost count, but every time I do I can’t help but sympathise.  It cuts right through to the core of the issue – why would you leave out key energy consuming items you actually find in an office when assessing its potential energy footprint?  Can’t say I really know why, but if you do, answers on a postcard please….

So here my friends starts the journey into this thing called the performance gap, and the gradual realisation that a Part L compliance assessment isn’t actually an energy prediction/footprint assessment at all, and all the stuff we know that is going to be installed and the way we are going to operate the building are sadly left to one side – because apparently we don’t need to know about that!

When we get the keys to a new building or space we want to know where our datum is, the point from which we are going measure and to know what’s in store for us.  However, getting this as part of the design and build process isn’t seen as the norm.  Why is that?  Perhaps it’s Part L conditioning a certain mindset that compliance is enough or that design teams feel they shouldn’t or can’t ask the client to spend more to do it.  Whatever it is, it’s moot, the point is it’s got to change.

To make the first small step towards change requires us clients to step up and disrupt the current way of doing things.  We can’t remain on the periphery of the process and we need to be clear we want to know these things, only then can a design team respond and do clever things and start to change the status quo.

Here at Derwent London, this has spurred us on to now formally mandate our design teams to tell us the likely operational impacts and energy consumption predictions of our latest developments.  I want to know what the building in question is going to be performing like with a 1:8 or 1:6 density ratio, 18 hours a day, 6 days a week. We need to face up to reality.  Gone is the 9-to-5, 5 day week pattern.  Many buildings are 24/7 and have been for a long time, and companies are squeezing more and more people into them with more and more stuff.  All this then becomes compound and instantly makes any idea of a notional building a fictional one, and in this instance I’d prefer a bit of science fact over science fiction.

It’s appreciated that when undertaking these sorts of exercises precision is difficult, and to coin Mr Rumsfeld’s ubiquitous statement there are “known knowns but there are also known unknowns and unknown unknowns…”

But you have to start somewhere, and something is always better than nothing in my book.