(Photo: Tan Hai Han)
The bigger house sits on a piece of land that tapers into a triangle at the back.

His children are only six and eight, but the owner of a multi-generational home in the Bukit Timah area has already made plans for when he has grandchildren.

He hired architect Wu Yen Yen to build a multi-generational home for his family of five, with plans to put in extra space for when his children grow up, get married and start their own families.

An attic was added to his two-storey house, which was also enlarged all around. The house has a built-up area of 7,093 sqf and a swimming pool at the back.

The owner of the house, who declined to be named, got inspiration from his neighbour.

(Photo: Tan Hai Han) The living room in the 7,093 sqf house faces a pool.

The latter had hired Ms Wu about three years ago to increase the size of his two-storey house to include an attic and a lift. Its built-up area is 6,135 sqf.

He also had her design it in such a way that a house within a house could be carved out in future for his children – a daughter, 19, and a son, 22 – when either gets married and starts his or her own family.

Ms Wu, 38, principal architect of Genome Architects, says that multi-generational homes are becoming more popular here.

"Ancestral houses are uniquely Asian, but aren't discussed a lot. Many people live in such houses, but current houses don't cater for the privacy of each generation – what if they want their own family space in the future? The designs of most houses don't plan for the future.

"These owners wanted homes that would take care of the people living in them now and also incorporate the growth of the family into its DNA."

(Photo: Tan Hai Han) One of these criss-cross staircases in the smaller house can be partitioned off in future. 

In the smaller house, two criss-crossing flights of stairs were constructed in the centre of the home. The built-up area here is 6,135 sqf.

One staircase leads up from the main entrance and dining area on the first level to the master bedroom and study on the second level. The second level houses a family recreation area and the 19-year-old daughter's bedroom.

The other staircase links the media room, which is at the back of the house on the first level, to two bedrooms on the second level.

One bedroom belongs to the homeowner's mother, while the other belongs to the 22-year-old son.

(Photo: Tan Hai Han) The 22-year-old son's bedroom loft (above) in the smaller house. 

In future, one of the two staircases can be closed up on both sides to create a separate living space and a private entrance. This would help create a "house-in-a-house", says Ms Wu. The media room would be converted into a living room with a kitchenette, while the two bedrooms would be part of the standalone unit.

It cost $1.34 million to build the house.

The bigger house, which was built at the same time as its neighbour, sits on a piece of land that tapers into a triangle at the back.

The first floor is occupied by the homeowner's mother, and the living and dining rooms. There is also an 8m-long pool.

The homeowner, his wife and their two sons have their rooms on the second level, while the attic is used as the children's study and play area. It cost $1.68 million to build the house.

(Photo: Tan Hai Han) A bathroom in the bigger house has his-and-hers vanity tops and sinks.

The owner plans to purchase a small empty plot of land at the back of his house to build an annex if his sons decide to live with him when they have their own families. His current house just caters for the existing members.

For both houses, Ms Wu used different materials on the facade to "divide" the house according to the different generations and new additions.

For example, in the smaller house, conwood – a natural wood replacement concrete panel – is used on the facade to highlight the part of the house that will be carved out in the future.

(Photo: Tan Hai Han) The facades of the two multi-generational houses.

In the bigger house, the new attic floor and its roof are clad in an off-form, timber-grained coloured concrete, showcasing the new part of the house.

Ms Wu says: "Both houses are multi-generational now though they showcase two families at different stages of their lives.

"The manifestation of each house's architecture depends on the owner's needs and wants, but both are forward-thinking."

(Written by Natasha Ann Zachariah for The Straits Times)