I read with interest Chris Wise鈥檚 article (4 June, page 23)

The reason we build in the wasteful way that we do is that most engineers (civil or otherwise) are afraid of their own shadow when it comes to answering probing questions over their designs. Consequently the safety factor is increased significantly.

As an example, one of the larger housebuilders has built a 10-storey building. After planning had been granted they needed to save money, so instead of a 250mm-thick slab they decided on a post-tensioned 150mm one. When the hairy-arsed bricklayers said: 鈥淲hat if you have problems in fixing the shelf angle to support the brickwork cladding? With the slab 150mm thick this is going to be expensive. Also what happens if you drill/fix through supporting wires?鈥� And so it came to pass.

Once your students qualify they will realise that the way forward is to toe the line over design, as they are not paying for it.

Peter O鈥橞rien, director, Peter O鈥橞rien, Construction Services