Construction Grade HPMC for Tile Joint Compound
You’re right, construction grade HPMC (Hydroxypropyl Methyl Cellulose) is indeed beneficial for tile joint compound, not just drymix mortar in general. Here’s how it specifically improves tile joint compounds:
- Enhanced Workability: Similar to drymix mortar, HPMC makes the tile joint compound smoother and easier to spread. This allows for better filling of joints and creates a more uniform finish.
- Improved Water Retention: Just like with mortar, HPMC helps the grout retain water. This is crucial for proper curing of the compound, preventing it from drying out too quickly and potentially cracking.
- Reduced Cracking: By retaining moisture, HPMC reduces shrinkage as the compound cures. This minimizes the risk of cracks appearing on the tile surface later.
- Sag Resistance: HPMC acts as a thickening agent, giving the grout a better consistency. This prevents it from sagging or slumping in the joints, especially when working on vertical surfaces.
- Smooth Finish: The improved workability and reduced sagging contribute to a smoother overall finish on the tiled surface.