As shells whizzed across Bukit Timah on Feb 14, 1942, a desperate British Lieutenant-General Arthur Percival was burning documents at Command House at 17, Kheam Hock Road.

That was the last time that Percival, who commanded the forces of the British Commonwealth, stepped into the house which had served as his official residence. The next day, he signed the country's surrender documents at Ford Factory in Upper Bukit Timah Road, marking Singapore's fall to the Japanese and three years of Occupation.

His colleague, the Rear Admiral of Malaya, Ernest John Spooner, who was based at Admiralty House in Sembawang, met a tragic fate. A vessel he had boarded to leave Singapore in the lead-up to the surrender was attacked by Japanese aircraft. Spooner was one of several people stranded on an uninhabited Indonesian island where he later died, according to war records.

The Command House, Ford Factory and Admiralty House, all integral to understanding Singapore's colonial period and war history, still stand today. They were gazetted as national monuments by the National Heritage Board's Preservation of Sites and Monuments (PSM) division in the 2000s.

The former Ford Factory, now known as Memories at Old Ford Factory, a museum run by the National Archives of Singapore, is in the midst of a revamp. The permanent gallery on the Japanese Occupation closed its doors in February and is set to reopen early next year.

Speaking to The Straits Times, heritage blogger and naval architect Jerome Lim said both the Command House and Admiralty House had been part of an intended trio of large residences constructed at the end of the 1930s for the commanding officers of the armed services: the army, navy and air force. Records show that there had been plans to build the final residence in Tanglin, but no physical evidence of such a residence exists today.

On Command House and Admiralty House, Mr Lim said these "had been built at the end of a decade in which the emphasis was on increasing Singapore's military might to support its role as an outpost for the British in the Far East".

For instance, Admiralty House was positioned in a strategic corner, away from the nearby naval base, to reduce its chances of being attacked; Command House, formerly called Flagstaff House, was in the centre of the island, close to military depots and the railway.

Mr Lim and PSM volunteer guide Katy Harris noted that both Admiralty House and Command House were heavily influenced by the Arts and Crafts Movement.

The late 19th-century and early 20th-century movement that began in Britain placed emphasis on craftsmanship in protest against the era's industrialised mass production. Arts and Crafts Movement buildings therefore emphasised traditional workmanship and highlighted the themes of nature, function, simplicity and exposed materials, among other things.

For instance, Admiralty House features an exposed brick facade on its upper level, just like Command House's exposed brick arches across its facade. Mr Lim and Ms Harris said grand parties used to be hosted at both buildings.

In an October 1941 account in the Singapore Free Press and Mercantile Advertiser dug up by Mr Lim, it was stated that Admiralty House, which was also known as Navy House, had played host to 350 people.

The report said the people "were recently entertained at a cocktail party in the dining and drawing room of the house and there was no crush at all, which gives you some idea of their pleasant spaciousness".

The same newspaper reported that "the biggest military wedding yet seen in Singapore" was held at Command House in September 1938.

Both buildings are used as schools today. Furen International School, a private boarding institution for O- and A-level students, has been leasing the Admiralty House compound since 2011, while UBS Business University has been at Command House since 2007. Both are renting the premises from the Singapore Land Authority.

Changes are on the horizon for Admiralty House, which will be part of a new sports and community hub. A completion date for the hub has yet to be announced, although some facilities are expected to be up by 2019.

One of Furen International School's directors, Mr David Mok, said he loves working in the old Admiralty House. "We're perched on a hill, in a quiet area. Former military officers often swing by to revisit the space. We will miss the building when we move out."

Meanwhile, Mr Lim hopes the rustic quality of the Admiralty House compound will be retained even with the redevelopment. He said: "There are very few places in Singapore with such lush greenery. While there's certainly a need for a new community space, I hope that there won't be too much intervention and that any works here will be done sensitively to take into account the history of the place."