I recently had the call to improve warehouse space block walls. What used to be a storage for rock wool insulation was being updated for use to store food stuffs, and food distribution materials.
At some point, so the legend goes, the rock wool would be adhered to a paper backing before it had time to cool and in some cases would smolder and create soot on the ceiling. In order to go from this sooty black to a more maintenance aesthetic white I would have to:
1.) Block fill the cinderblock with 15 gallons of block filler.
2.) Roller seal its resiny nature over the "twin T" pre-cast concrete ceiling with 10 gallons of Kilz.
3.) Spray a "dry fall" white over that with 10 gallons .
4.) Spray and back-roll 10 gallons of a high gloss white acrylic paint.
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Before.
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After.
Afterwards I would also be called back to help make a perimeter line around the rough asphalt floor surface with a quick-set mortar mix, and paint over that to a sharp 18 inch line.