ATLAS Uni-Grunt 5KG

The VOC line is the one that decides interior work. Maximum content is declared as 1.92 g/l against 30 g/l permitted under Cat. A/h/FW, and the primer is solvent-free, water-soluble while wet and colourless once dry, so it leaves no cast under a pale emulsion paint. The classification line matters to a specifier rather than an applicator: because the primer is not a construction product there is no declared performance and no DoP number attached to it.

Dilution and Application, Indoors and Out

The wall wants to be dry and clear of dust, dirt, oil, grease and wax, with loose layers taken off first. The primer is supplied ready to use and is not mixed with anything or thickened, so dilution is the only variable left on site:

1. Weak and highly absorbent masonry — cement-lime plaster, aerated concrete, silicate brick, mixocrete screed — takes it undiluted, or twice at 1:1.

2. Normal absorbency under a screed or plaster takes one coat at 1:1.

3. Normal absorbency under finishes, paints, waterproofing or adhesives takes one coat at 1:3.

Lay Atlas Uni-Grunt 5 kg on thin and even with a roller, brush or sprayer and stop at saturation — puddles and streaks are a sign of too much, not of thoroughness. When the surface has dried, wet it and watch how quickly it takes the water in; a wall that still drinks gets primed again. Above it, an Atlas adhesive mortar can follow after roughly fifteen minutes, while painting, wallpapering and tiling wait the full drying time of roughly two hours. Both intervals are tied to temperature and humidity rather than to a clock.

ATLAS Uni-Grunt 5KG