Schönox AST 33lb

Synthetic Gypsum-Based, Rapid-Drying, Smoothing and Patching Compound provides a smooth finish on various substrates in interior areas. Can be installed as a true featheredge up to 1/4″. Excellent for light repair over gypsum substrates in multi-family applications. Over cement, preferably, use Schönox SL.

Emicode - low-emissions product. HPS Schönox Subfloor Solutions

Technical Data

Compressive Strength

(ASTM C109/mod-days air cure only): 23N/MM sq / 3600 psi at 28 days


(depending on texture of substrate) Per unit of 4.5kg/10lbs.:
Approx. 594 sq.ft. when applied as a true featheredge
Approx. 109 sq.ft. at 1/8″


EC 1PLUS : very low emission


IEQ 4.3 Low-Emitting Materials-Flooring Systems, 1 point
MR 1.1 Building Reuse Maintain Existing Walls, Floors and Roof, up to 3 points
MR 1.2 Building Reuse Interior-Maintain Existing Interior Nonstructural Elements, 1 point
MR 4 Recycled Content, up to 2 points

Working Temperature

41°F – 90°F

Pot Life

Approx. 20 minutes at 68˚F

Ready For Covering

After approx. 30 minutes when applied as a true featheredge
After approx. 12 hours at 1/8″ thickness

Shelf Life

18 months unopened


33lb. net weight in paper bags

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