Sir – So far councillor John Tanner has failed to explain why his ‘Campaign for a Cleaner Oxford’ does not include compulsory updating for thousands of private and council tenancies that need double glazing, insulation and central heating to avoid lost energy going through the roof.

It would not be a matter of persuading landlords to comply, it should have been a legal requirement decades ago.

The authorities are doing too little too late, much like the production of animals that requires a massive waste of food, water and energy. The environmental damage caused takes second place to the epidemic of health problems like numerous cancers and circulatory diseases which are all caused by consuming animal protein.

Victor Manning, Oxford