National Development Minister Khaw Boon Wan said Monday that he has directed the Urban Redevelopment Agency (URA) to tighten the rules on the developers of executive condominium (EC) projects to prevent them from profitting off the sale of free space.

Mr Khaw said that he was originally "baffled" that developers were "short-changing" themselves by launching such massive units, as they could have made more money by using the space for two or three normal-sized apartments.

After looking into the matter, he realised that developers were using a loophole in the rules to profit from the super-sized units. Currently, they do not have to pay development charges on outdoor roof terraces, as URA wants to encourage developers to build more communal outdoor space for residents to enjoy.

For example, the presidential penthouse suite at the CityLife @ Tampines project has a roof terrace of 1,600 sq ft, on which the developer did not have to pay development charges.

"Developers' selling off free spaces to make additional profit for themselves is not improper under current URA rules," wrote Mr Khaw. " But as more developers do so, with larger private roof terraces and "private enclosed spaces," communal space in the development that benefits all residents will correspondingly shrink."

Furthermore, buyers may find themselves disappointed later on when they realise that the outdoor spaces they have paid for are not allowed to be covered up or enclosed, he said. He has directed URA to "review this policy and have it fixed."