Property watchers contacted by The New Paper said it is "not unusual" for families to buy plots of land for communal living.

"While erecting condominium units to house families are rarer, it is common for bungalow owners to build homes within their compounds for their children to live in," explained HSR Property Group special adviser Donald Han.

Mr Colin Tan, head of research at real estate consultancy Chesterton Suntec International, said these families who chose to build condominium units probably did so because "they have special needs like living near the city".

Houses can be built only outside the city area.

But Mr Tan said there is a downside to building condominiums - they are expensive to maintain as the property taxes will be higher, especially once the new tax structure takes full effect in 2015.

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