REQUIREMENT:
Architectural and/or exposed aggregate finish to concrete surfaces.Production of a physically roughened / textured or “keyed” surface for subsequent bonding and / or rendering.
PRODUCT TO USE:
CALSTRIPSurface-Retarding Form Release & Keying Agent
HOW TO SPECIFY:
All formwork shall be treated with one liberal coat of Cementaid CALSTRIP Surface Retarding Form Release & Keying Agent, applied at least four hours before pouring concrete, at a rate of approximately 1 litre per 6 sq. metres, depending on depth of surface retardation desired.
The surface may be treated up to one week before pouring, but should be protected from rain. During removal of formwork (within 3-14 days), the exposed surface should be immediately scrubbed down with a bass broom, or hosed with high pressure jets to remove retarded surface material and roughen for rendering/bonding, etc.
EFFECTS:
CALSTRIP forms a tough, semi-glazed coating on formwork, which very slowly dissolves into the concrete at the interface between fresh concrete and formwork, to prevent set of surface mortar. This allows removal of retarded surface mortar by hosing/brushing after stripping, to leave an architectural/textured finish which is also ideal for promoting tenacious bond.Rate of application controls depth of penetration of CALSTRIP and therefore depth of retardation.
Does not stain render. Fully compatible with other CEMENTAID products.
NOTE:
Fresh concrete should be placed against the CALSTRIP treated forms in a manner so as to avoid/ minimise premature removal of the CALSTRIP retarding film by abrasion.
WHERE RECOMMENDED:
All formwork for concrete surfaces / finishes where an architectural and/or roughened or textured surface is required.
For air-exposed, horizontal surfaces (e.g. slabs, capping, stones, etc), apply CALSTRIP to the surface, followed by covering with plastic until initial set, then hose-off retarded surface material, as per normal.
Consult CEMENTAID for special use for exposed aggregate work.
