Understanding Cement Grout
Cement grout specifications and calculations are crucial for proper installation and durability.
- Mix Ratios Standard: 1:3 cement to sand. Non-shrink: add 1 part lime. Structural: 1:2:3 (cement:sand:aggregate). Water ratio: 0.45-0.50 w/c for workability.
- Coverage Rates 1/8" joint: 0.1 lb/sq.ft. 1/4" joint: 0.2 lb/sq.ft. 3/8" joint: 0.3 lb/sq.ft. Add 10% waste factor. Consider joint width variations.
- Strength Properties 28-day strength: 2000-4000 psi. Initial set: 1-2 hours. Final set: 24 hours. Compressive strength increases with decreased water ratio.
- Application Types Sanded: joints >1/8". Unsanded: joints <1/8". Epoxy: chemical resistance. High-strength: >4000 psi for structural use.
Installation Guide
Preparation Steps
Clean joints 2/3 depth. Surface temp 50-90°F. Pre-dampen in hot weather. Mix small batches (20-30 minutes working time). Test color match.
Application Methods
Float at 45° angle. Pack joints completely. Tool when thumb-print hard. Clean within 15-30 minutes. Cure 72 hours minimum.
Quality Control
Slump test: 8-11" flow. Check for voids with sounding. Color consistency between batches. Compression test samples for structural grout.
Maintenance
Seal after 28 days cure. Clean with pH-neutral cleaner. Inspect annually for cracks. Repair damaged areas promptly. Reseal every 2-3 years.