Alan Mitcham cautions against the influence of the building lobby and Tom Woolley calls for an urgent investigation to evaluate the dangers of over-cladding

What a tragedy the fire at Grenfell Tower in west London is (Twelve confirmed dead but police expect further fatalities after tower block blaze, theguardian.com, 14 June). My heart goes out to the injured and the bereaved.

Some reports seem to be saying that the insulation cladding may have played a role in quickly spreading the fire, so I wanted to mention the situation here in Germany. For many years the German government has been subsidising the external insulation of buildings, with a great number having been reclad with blocks of synthetic insulation.

In theory this is all very good, but reduced ventilation creates problems of dampness and mould – and, of course, the fire risk is increased, with even more regulations having been passed, including installing “fire ridges” on roofs between buildings. It seems that the German building lobby got its way, with rules and subsidies on insulation standards having generated a massive surge in orders for them.

If that were not bad enough, a recent ruling has reclassified certain commonly used classes of synthetic insulation as “toxic waste” so that overnight millions of properties that were thought to be environmentally friendly have become “toxic”. This ruling means that, in the case of removal (or fire), property owners are faced with an enormous bill for specialist clean-up and disposal requirements.

Yes, we need to protect the environment and, yes, it is good to save energy, but when commercial lobby interests get involved, things are guaranteed to go pear-shaped.

Alan Mitcham

Cologne, Germany

• The horrific events at Grenfell Tower raise serious questions about the materials used to over-clad buildings. The insulation materials used may have been a factor in the rapid spread of fire up the tower block. Other similar fires have occurred, such as Lakanal House in London in 2009, following renovations, involving over-cladding, but the inquest failed to probe this adequately.

A full, urgent and independent investigation is required to evaluate the dangers of over-cladding and to evaluate the risks to other tower blocks that have had similar measures. It is not enough to wait for an inquest as the lives of other tower block residents may be at risk. Regulations should be changed to ensure that only non-flammable materials are used for insulation.

Tom Woolley

Crossgar, County Down

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