Definition - What does Block Filler mean?
This is a filler material used under epoxy, alkyd and latex top coats for interior and exterior concrete finishes. It is used in masonry preparation on concrete block and cinder block (poured and precast). It is used before top coats so that the surface assumes a flat, smooth and uniform profile. It is required for professional quality finishes since it seals void, porous, cracked and pin-holed surfaces.
Corrosionpedia explains Block Filler
The substances commonly used in making this are termed low volatile organic compounds (VOCs), and thus contain vinyl-acrylic resin, extender pigments and titanium dioxide. Most of the block fillers have a volatile organic compounds (VOC) ratio of below 50 g/L.
Surface preparation is required before using this filler since moisture, dust, rust, oil and other foreign particles might tamper with the adhesion efficiency of the block filler. The mode of application is determined based on the preference of the users; it can be brushed, squeegeed, rolled and sprayed (conventional or airless). However, each mode of application has its requirements of use.
To obtain a quality surface modification, the instructions are based on the right temperature, humidity and film thickness; these factors are proportional to the dry time to be used. When used, it produces a good concrete finish with desirable uniform texture.