Case 1

Good Practices

Design

Recommend surface treatment and protection in accordance with SS 509-2, BS 8221-2 or equivalent. Ensure proper detailing of window, door, and abutment points where water seepage can occur and
cause delamination. Design movement joints are recommended on the structural concrete in accordance with BS 6093 or equivalent. As early as 1992, the then Public Work Department (PWD) — now Building
and Construction Authority (BCA) — issued a memo discouraging the use of tiles (ceramic and stone
tiles bedded with adhesive) on façades of buildings exceeding 4 storeys.

Construction

Sufficiently remove curing agent (used for early stripping of formwork) to ensure proper adhesion on
the substrate. Ensure proper substrate preparation (cleaning) prior to application of plaster/tile finishing. Perform quality workmanship on façade through the correct handling and angle of application to prevent delamination and debonding in accordance with BS 8000-0 or equivalent. Lay adhesive and tiles in the sequence according to the manufacturer’s instructions. Adopt the performance requirements for curtain
wall, including safety in accordance with BS EN 12179, ASTM E2270-14 or equivalent.

Plastering

Proper preparation of the background is important prior to the application of the plaster. Cleaning of the background is especially important if curing agent is being applied to cater for earlier striking of formwork. The background should be cleaned by flushing with clean water and brushing off any dirt.

For better bonding between the plaster and the background proprietary bonding agents maybe used such as emulsion of PVAC or polymers or bituminuous solutions or emulsions can be applied.

An important aspect is also the correct installation of plaster by the plasterer. The correct handling and angle of application by the plasterer using the trowel is also important to the prevention of delamination. Refer to the video on the correct technique of application.