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Ductwork Is Difficult?

Ductwork is Difficult?

Quality, Consequences and the Construction Industrial Complex (part 174).   

At the end of 2018 I am starting to reflect on the good and bad projects. However, I keep coming back to ductwork installations, they must be really difficult, right? 

We can put a man on the moon, Elon Musk exists and Felipe Massa’s pit crew can change all four race car tires in 1.92 seconds ( ). So why can’t we coordinate and install building systems correctly?







Evidence points to human ingenuity and industry consistently improving over time via incremental innovation plus improvements in human and industrial processes. So why is the construction industry stuck in a perpetual loop of mediocrity, poor outcomes and diminishing competence? When was the last time you saw on site, a refined, process driven installation with a focus on zero defects? Go ahead, I will wait……..

Take the example of ductwork installation. Ductwork is not rocket science, the principles are well understood and we have CAD and CAM to help. Why is ductwork installation not slick and refined like a race car tire change? In the last six months I have seen two examples in plain site of mediocrity or crimes against the owner, you decide.

Photo 1 tells a story of indifference. 

Forensically I conclude the shaft was constructed with the duct penetration cut prior to any real thinking or coordination with the ductwork contractor. There is no excuse for this, it is poor construction and engineering. The real damage here is the life long systems effect caused by a ~ 40% reduction in duct free area due to the misalignment requiring a 45 degree transition duct. This is a result of zero ownership, zero accountability and zero consequences to the main contractor. 
















Photo 2 tells a story of incompetence. 

I feel triggered by this photo. The design engineer, resident engineer, contractor and installation / QC foreman that accepted this installation suck IMHO, because:

  • This is the high pressure inlet duct onto a VAV box but has low pressure flexible ductwork installed. 
  • There is zero coordination between first fix and second fix ductwork installation.
  • There is misalignment between first fix and second fix ductwork installation resulting in a poor systems effect for the VAV box.
  • There is no straight inlet condition to ensure stable airflow onto the VAV box air flow sensor.
  • At VMax, the VAV box inlet duct generates high noise levels and leaks. 
  • VAV box performance will be compromised over its operational life span.

Am I missing something? Is it not possible to install straight, aligned ductwork in the digital age? 

In each example above, the main contractor is responsible because it was done by his subcontractors. Contractually, all main contractors own all the responsibility for installation outcomes by all their sub’s. One of the reasons contractors have poor reputations is that they leave evidence of their poor work in plain sight. Maybe they are such gangsters they don’t care about the long term consequences of their work or, what their clients think? 

Construction is a culture of low expectations fuelled by the fact that everyone involved in the design, construction and acceptance of the above examples will not be involved in the running or use of the buildings and no, P3, PFI, DBFM or D&B will not fix this. The only thing that will fix this are dire, actual consequences for poor work. 

Quality is a million little things done well that compound to excellence in operation. When we finally move to evidenced based building operation via IOT and blockchain based records then maybe we may finally see some accountability leading to high quality outcomes. I hope so, in the mean time I am starting to question the sanity of clients who accept these poor outcomes with out consequence. 

Is the owner / contractor relationship a perpetual cycle of reciprocal abuse? Maybe!

Twitter: @BLDWhisperer

Related posts & links:

#122 – System Effect – “the problem that keeps on giving” ( )

#143 – Site House Keeping is a KPI ( )

#147 – Delusion is an Opportunity ( )

#168 – Rising Factories ( )

Edifice Complex Podcast


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This Post Has One Comment
  1. Great blog! We bring the Aeroseal solution into Europe since 2015. 18 service provides so far. Only one in the UK until today! I would be pleased to cooperate with you in order to get ductwork done right in future in order for a higher energy efficiency! Best regards, Jörg Mez

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