Locomotives were fitted with condensers to reduce fumes, but "venting off" was still needed in open-air sections to relieve the condensers and keep the tunnels free from smoke. In this upmarket area, the railway company hid this unsightly practice from residents. The false façade also maintained a continuous frontage along a prestigious terrace. The façade is 5 feet (1.5 m) thick with 18 blackened windows. The doors have no letter boxes.
In the 1930s, a hoax was played on guests who were sold ten-Guinea tickets to a charity ball at Leinster Gardens, only to turn up in evening dress to discover the address was fake.