For a cheap and simple air-con unit: take the blue blocks used in most cool bags from the freezer; put them in a metal saucepan (we use a wok); place them in the airflow of a fan. Remember to put them back in the freezer in the morning. Sleep tight!
Helen Caton
Woodmancote, Gloucestershire
• Putting external shutters on windows is a good idea (Letters, 27 May), but windows open outwards in the UK and inwards on the continent, which makes shutters possible and efficient.
Claudine Burton
Doddinghurst, Essex
