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This Is Not OK!

This is not OK!

​Quality, Consequences and the Construction Industrial Complex (part 43) – All IMHO:

Quality is a million little things, that when done well, provides a cumulative effect that is greater than the sum of the parts. In effect, 2+2=5.

For example, my laptop is an Apple Mac book. Whilst it looks nice, there is a quality to its feel and operation that transcends its utility and makes it a great user experience. I know, but mostly feel, that Apple have extended the design and build quality beyond the external to the internal things I cannot see. The cumulative effect is that millions of people and I have brand loyalty, and because of this, Apple is one of the most valuable brands in the world.

How can building design and construction be like Apple?

This is too big a question. However lets look at a specific example, one of the million little things that need to be done well to create a quality outcome. For example, lets look at a humble AHU cooling coil. 

In the event that the design engineer has sized an AHU and cooling coil correctly, plus selected the correct commissioning and control valves that are sized for authority (this is more unusual than people realize). It is still possible to install the commissioning and control valves poorly, making them sub-optimal and therefore effect the performance of the AHU, energy consumption and space conditions. Why does it matter and who even thinks about this (apart from delusional geeks like me)?

It matters of you what high quality outcomes and high levels of performance. It matters for mission critical plant and in the long run for the operation of the building. It matters because a million little things done well provide a cumulative effect that is greater than the sum of the parts. In effect, 2+2=5.

Take the photo at the top of this post. The Commissioning double regulating valve is installed in a “sub-optimal” location. Specifically it is a poor installation IMHO because:

  • For accuracy of flow measurement there should be at least 10 straight pipe diameters upstream and 5 straight pipe diameters downstream. Accuracy of this valve could be as low as +/- 35%.
  • This example shows “lazy” installation. “Just fit it to the elbow and save a pipe cut”.
  • Low measurement accuracy impacts balancing, and any decision to up or down rate a system pump.
  • False readings can result in over regulated valves, additional pump head and reduced life for the valve.

For any device that regulates, measures and controls flow, the installation matters. The rule of at least 10 straight pipe diameters upstream and 5 straight pipe diameters downstream is a great installation rule of thumb. Yes, in real world installations space can be tight, but the installer should always try and locate the commissioning and control valves with the most stable entry and exit conditions. Therefore if the minimum 10 in and 5 out rule of thumb cannot fit, try and keep the installation proportional to 10 in and 5 out. Most importantly don’t just “slap it in”. Think about it if quality matters to you and your client!

For visual people, the diagrams below summarize this installation rule of thumb.  

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