Jennifer Deeney’s tragic story makes sobering reading, as does Tony Bingham’s article on the wall collapse (1 October). They emphasise the fact that freestanding walls can be deathtraps.

Such walls are often built by untrained people. The masonry is often inadequately bonded, and foundations may be virtually non-existent. It may also lack necessary reinforcement and adequate maintainance.

It is time we rethought the guidance on this subject. We cannot expect people to diagnose when their walls are dangerous, so they must be built properly to start with. My view is that no 100mm-thick wall should be built higher than 450mm, and that 225mm-thick walls should be limited to 1.8m. These restrictions should be relaxed only if the wall is constructed in way that will ensure adequate performance for a long period. If we do not take action, I fear we will continue to suffer deaths and injuries from such walls.

G Mathieson, G Mathieson Associates