Environmentally friendly: The clean and tidy construction site at the Housing Authority's Un Chau Street Phase 2 project uses precast concrete paving slabs over the ground level.

The Housing Department has introduced hard-paved construction into all building and piling sites as part of its continued efforts to promote environmentally friendly, healthy and safe construction.

Laying concrete or metal slabs over sites, or pouring conrete over them, has proved to be effective in storing materials properly, minimising waste, reducing dust and enhancing site safety during the construction process, the department said.

Other advantages include better housekeeping while providing hard ground for temporarily storing building materials.This helps prevent damage to or contamination of the materials.

From part to the whole of building sites may be paved with permanently used materials such as precast concrete paving slabs or metal plates, or poured concrete to be used temporarily.

Four projects - the Un Chau Street Phase 2 and Phase 4 Development, Shatin Area 4C and 38A, Kwai Chung Flatted Factory Redevelopment and Ex-Chai Wan Estate public Housing Site Piling Works - are among those in which contractors' have taken the initiative to hard-pave the sites themselves.

The precast slabs are highly durable and reusable, reducing the amount of construction waste generated on-site.