Building owners must now look for a registered contractor to carry out renovation work that involves structural change.
The 'minor works control system' from the Buildings Department, which takes effect today, is intended to regulate the quality of small-scale renovation work on private properties.
Deputy director of buildings Lam Siu-tong said the control system would simplify a long-standing statutory procedure which property owners had often ignored.
'Under the previous legislation, owners were required to hire building professionals, say a structural engineer, to carry out all sorts of work even if it was as minor as installing a drying rack,' Lam said. 'This was a big burden in terms of money and time, and the result is that many structures were illegal.
'The new control system will provide a lawful, simple means for building owners to carry out such work.'
The system classifies 118 renovation procedures into three types according to complexity. Individual building contractors, upon registration, can only take up the simplest type, such as installation of supporting frames for air conditioners or the repair of windows. These individual contractors are not allowed to take up more complicated work such as slab opening, external work or staircase and lift installation, which can only be conducted by a contractor company, architects, surveyors, and structural or civil engineers.