Exposed Aggregate Floor Process:
Concrete Slab placement for Aggregate Exposure when polishing:
- Install concrete mix without the use of vibrating “bullet” or other methods which specifically push aggregate down below the surface. After “striking off” to make a level surface, lightly trowel the slab using a Bull Float or Fresno float to smooth the surface free of humps or hollows. Do not walk back through or place any objects on wet cement that could disturb the even placement of the aggregate. When the slab has set up enough to be walked on it should be power troweled to consolidate the surface. Apply Lythic Densifier to add strength to the surface cap.
- A floor flatness rating of 40 and a floor levelness rating of at least 30 is recommended. Mounds or dips are not acceptable as they may not be removed by grinding to polish the floor.
- When power troweling the floor, take care not to “Over Trowel” or “Burn Out” the slab. Concrete finishers are required to trowel the surface to a flat, consistent level and leave minimal trowel marks. Eliminate any boot prints or unnatural imprints in the surface. Make sure to stop troweling before the concrete slab turns from an even grey to a blackened color…do not burnish the slab. Do not add water or foreign material to surface upon finishing. As an additional precaution an onsite representative or foreman of the selected concrete finishers should contact your approved Professional to review the requirements for the above finish.
- After the concrete has been finished, do not store objects on the surface for at least 7 days after the pour as it will cause discoloration.
Grind and Polish to Expose Aggregate:
- Grind with metal bond diamonds to remove “cream” from the surface and expose aggregate.
- “Float” cementitious skim coat product over the floor to fill pin holes and “rock pops.”
- After the next grind, densify the surface.
- Polish with successively finer diamond tooling to remove scratches and create surface reflectivity.
- Apply Lythic Protector and burnish after final diamond polishing step.