 A 1 @,@ 600 @-@ square @-@ metre ( 17 @,@ 000 sq ft ) two @-@ storey detached house – often called a bungalow in Singapore – with European and Asian features , Sri Temasek has a symmetrical layout consisting of deep verandahs surrounding central living spaces . Notable architectural features include arches on its upper level , an intricate timber arcade with a mixture of eastern and western decorative motifs , and a Chinese moon gate ( a circular gateway ) on the building 's second floor . Although few records exist concerning the moon gate 's construction and usage , it is known to have made its appearance in the house in the 1960s and to have been designed and built by William <unk> , a pre @-@ World War II Comptroller of Government House and a professional furniture designer . It is constructed of <unk> , teak and meranti wood . In the middle of the driveway in front of the house , there is a brick pit that was originally used by horse @-@ drawn carriages . The house was gazetted together with the Istana as a national monument on 14 February 1992 . 
