the property , in the leafy south east london suburb of chislehurst , was designed and built especially for government officials as the cold war intensified in 1951 .
the site was chosen because the wooden area surrounding the building afforded it secrecy and the house was built with five foot thick concrete walls .
the glass house in chislehurst , which was formerly a secret cold war bunker and has now been transformed and is up for sale for £ 3.5 million that