1. Building Appraisal and Demolition Plan

Prior to carrying out any building demolition, detailed building appraisal by means of surveys and appropriate assessments shall be required. In general, the surveys shall include a Building Survey and a Structural Survey with photographs or videos taken for future reference. Based on the findings of these surveys, a demolition plan shall then be prepared and submitted to the Buildings Department for approval. The demolition plan must also be accompanied by a report together with structural calculations assessing the stability of the building to be demolished and all affected buildings, structures, streets, land and services.

• 2.1.1           Building Survey

• Record Drawings

Prior to the Building Survey, the existing record plan, including layout plan showing adjoining properties, pedestrian walkway, roads and street, etc. shall be retrieved.

• Survey Items

The Building Survey shall cover the following:

• The construction materials;
  • The existing use and, if possible, the past uses of the building prior to demolition;
    • The presence of wastewater, hazardous materials, matters arising from toxic chemicals, flammable or explosive and radioactive materials, etc. and possible presence of materials which can contribute to air pollution and soil contamination;
    • Potential dangerous areas, e.g., abnormal layouts, presence of enclosed voids, and non-ventilated light wells which may trap obnoxious gas at the bottom;
    • Adjoining properties and site conditions, such as the existence of slope and retaining wall, wall supporting ground, illegal structures, bridges, underground railway and its above ground structures, including entrances, vent shafts, distribution substations, traction substations, plantrooms, overhead railway structures, surface track sections, overhead cables or guy wires, and other utility service connections;

• Drainage conditions and possible problems on water pollution, flooding and erosion, especially on sloping sites and water receiving bodies;
  • Shared facilities with adjoining building, including common staircases, party walls, and possible effect on it, such as self-enclosed walls to the adjoining buildings, during demolition;
    • Hoarding and covered walkway requirements;
    • Adjoining pedestrian and vehicular traffic conditions;
    • Available headroom, clear spaces and distance of building from lot boundary which may affect the loading operation and transportation of building debris during demolition;
    • The sensitivity of neighbourhood with respect to noise, dust, vibration and traffic impact. For building/structures to be demolished, confirming whether it is within the scope of the designated projects specified in schedule 2 of the Environmental Impact Assessment Ordinance;
    • Available site area to allow on-site sorting of building debris; and
    • Street furniture such as fire hydrant, parking space/metres, street light, street sign and hawkers’ stalls which could be affected by the demolition project.

• Hazardous Materials

• Unless the Building Survey reviews that no obvious hazardous material is present in the building, the Authorized Person shall cause proper sampling and testing for the hazardous materials;
  • In the case when hazardous materials e.g., asbestos containing materials, or petroleum, are present, they shall be removed and cleaned/disposed of according to the statutory requirements administered by the Environmental Protection Department, Fire Services Department, Labour Department and any other Government Departments, referred to in Appendix D;
    • In the case when the site has previously been used to store chemicals, and other dangerous goods, soil contamination assessment shall be required at pre-demolition stage and/or post-demolition stage; and

• In the case when the site has previously been used to store explosives, special procedures to ensure no explosives remain on site will be required.