Today’s release of what are fairly obscure figures to most people show brick stocks plunging to the lowest level since the 1980s and a surge in deliveries comparing the latest quarter with a year ago.

A rise of 16% year to year should be something to write home about, shouldn’t it?

This apparent boost to production must be of interest to the armies of economists and commentators keen to spot potential effects that can be tracked back to the Help to Buy scheme?

Meanwhile, they should be of interest too to the construction trade press which has already picked up on materials and labour shortages in the house building supply chain. So what’s happening to a core house-building material surely has to tell us something about activity in the sector and the stresses within the supply chain?

It is against this background that these data from BIS, the business department, can provide a bit of fun. That’s to say they can be interpreted in various ways depending on what reality you are looking for.

OK so what are we looking at?

I’ve put together a chart (right) of the quarterly data you’ll see if you open up the latest release. It shows a sharp rise in deliveries and a strong rise in production, but not enough to stop stocks of bricks shrinking to a low level.

In figures deliveries in the three months to June were up 16% on the same period a year ago. That’s strong growth. That fits the housing booming story.

But for comforts sake at this point I think we need more context and to look at the data over a slightly wider time period.

First off if we look at the first half of last year and the first half of this we see that the rise in deliveries is just 2%. That’s not so impressive. So perhaps there is no house building boom going on.

But the stocks figures look interesting, they are at the lowest level you’ll find in the data published on the website. That does indicate a potential level of stress. Maybe builders are turning to other materials as getting bricks is a struggle.

What’s more if you turn to the pages on building materials imports you’ll find imports of bricks rising. They are at levels not seen since 2008 and probably proportionately higher in relation to house construction than we will have seen for some while.

So there is some stress it would appear with UK-based production not meeting demand. And if we look at UK production on an annualised basis if anything it appears to have been declining over the past year, despite the recent uptick.

So maybe we have a composite of a drop in production meeting a rise in house building, with builders turning elsewhere for bricks.

Given the Government’s aim of boosting building materials exports this would not be the best news. But it’s early days.

Let’s however pull the camera back and take in a much wider time frame. The second chart (above) shows brick production over the past 60 years.

It reveals three main things instantly:

  • That brick use and production are in long-term decline
  • That production and deliveries track very closely
  • Perhaps less obviously, that there was a change in the proportion of stocks carried by producers in the late 1980s

To get a clearer insight into what goes on I thought I’d track house completions and brick deliveries over time (right). This has problems because I have not accounted for time lags, but the broad pattern is interesting.

We see, again in the late 1980s, an apparent break in a relationship. This time it seems that on average builders were using fewer bricks per house. Tracking this in a separate graph we see that this is a fairly long-standing trend.

I would be cautious about drawing too many conclusions given the way I have wrapped the data together.

What’s important to note is that technology has changed. We have to consider changes in how homes are put together with, for instance, blocks and timber frames replacing common bricks.

If we look at the relationship between house building and facing bricks we get a very different picture.

Here we see a long period from the 1970s to the early 2000s when the use of facing bricks had increased in proportion to house completions. This is the period where system building had fallen out of favour.

The move towards more flats in response to newly introduced planning guidance in the early 2000s may well account for the reduction in the number of facing bricks used per new home built post 2000, a change that is evident in the final chart.

Similarly the rise in the proportion of facing bricks we see in more recent times after the industry hit rock and began to recover appears to reflect the shift in house builders’ product mix from flats to bigger homes.

Certainly there is plenty in the data to spark thoughts worth greater exploration.

The shift in the balance of stocks in the late 1980s is interesting. Could the reason be that, rather than builders or brick factors holding onto stock, the stock is now held in greater proportion in the producers’ yard, delivered “just-in-time” rather than getting kicked around building sites?

What is the effect of low stock levels on brick imports? Should we expect a surge of imports?

How quickly can supply respond to a sharp rise in demand after it has been so badly depleted for so long?

How have brick prices in the past responded to a rapid rise in demand when the supply base was depleted?

What is the rate of substitution and the use of other materials when house builders struggle to get bricks or find price rises a bit too steep?

Fun stuff if you like that kind of thing and have the time.

Either way hopefully this trip through the brick production, delivery and stock figures helps to reveal that they have much to tell us about how the house building industry is moving.

But equally they can easily lead us to draw false conclusions, if we don’t look at them in context.

To answer the question in the headline, well maybe.