Sometimes the smallest thing triggers the strongest reaction. Like a seemingly harmless comment, buried in a chain of email correspondence:
Not much of a link between wall and floor insulation, so whoever provides the Energy Performance Certificate needs to be aware.
The comment, from an Approved Inspector to the developer whose site he was inspecting, might sound diligent enough. But I could only see the opposite, and it led me to write an (unpublished!) diatribe called, ’The UK Construction Industry is Broken’.
In the wake of the tragedy at Grenfell Tower in London, plenty of other commentators had much greater justification for diagnosing the industry with a similar state of health. I had no wish to join the chorus; my reaction was born of simple frustration at observing consistent failings that, although every bit as genuine, sounded trivial compared to the loss of life we all witnessed.
What was wrong with the floor/wall junction?
Insulation is most effective when installed as a continuous envelope. Any interruption to that envelope is called a thermal bridge; the point at which a ground floor meets a cavity wall is a well-known thermal bridge, because building the inner wall leaf off the foundation inevitably disrupts the continuity of the insulation between the adjoining elements.
Good design and diligent workmanship can reduce the impact of the thermal bridge, and typical methods for doing so - perimeter upstand insulation to the floor slab; starting the cavity wall insulation at the correct level to ensure overlap with the floor - are well documented. They should also be common practice.
Noting this particular installation as inadequate begged several questions:
Did the construction drawings specify the treatment of the detail?
Did the contractor know how to construct the detail properly?
Did the inspector feel they had fulfilled their duty sufficiently in the way they drew attention to it?
Quality communication = quality control?
The motivation to revisit this topic came in the form of this article about Building Information Modelling, or BIM. It argues that all of the tools are in place for the management and exchange of digital information to be a success throughout the supply chain, on projects of any scale.
What’s missing is collaboration between the people using those tools.
Over the last couple of years I’ve written pieces on various topics (including BIM), approached from various angles, many of which have ultimately centred on the importance of communication to achieving better buildings.
I’ve read plenty more articles by other people making exactly the same point. Despite my genuine intent in raising the issue, it’s hard to escape the feeling that ‘communication’ risks becoming a buzzword or platitude that provokes no tangible reaction from readers.
See some of the incredible projects that an effective and collaborative use of BIM has delivered and you will believe that it works. On a smaller scale, I like talking about communication because I’ve seen the genuine benefits of initiatives like toolbox talks for new products, working with contractors to achieve improvements on site.
Sadly, there are too many projects and sites where the benefits of better communication aren’t understood or realised. Rather than achieving genuine collaboration, each party aims only to cover their own back and avoid potential liability for any faults.
Which brings us back to...
A building inspector is responsible for assessing the quality of work carried out on a site. The email comment about the thermal bridging detail acknowledged the problem, but implied no intent to do anything other than have an Energy Assessor account for it elsewhere.
I've noted it, not my problem now.
There was no suggestion of attempting to educate the contractor or have the work rectified. There was no suggestion that the developer wanted the new properties to demonstrate attention to detail.
The casual acceptance of unsatisfactory quality means questions only come later, when the willingness to rectify issues is barely evident because of the time and money needed to get the job right - and that’s before considering the economic and environmental cost associated with increased energy use, higher energy bills and higher-than-predicted carbon emissions.
It’s possible that the as-built energy performance calculations showed a detriment to the predicted performance but, ultimately, the work was likely signed off and the properties sold, leaving the occupants to suffer cold draughts and excessive heat loss.
And when it comes to selling someone a house, I’m confident that absolutely no one communicated that to the buyers.