Description
Ardex FS-DD is a non-sanded, cement-based grout specially formulated for polished porcelain, where a standard sanded grout risks scratching the tile’s finish during application and cleanup. Its fine formulation still handles joint widths from 1mm to 4mm, covering the narrow, tight joints common with rectified and polished large-format tile.
The product’s water repellency comes from a special hydrophobing agent, which keeps dirt from entering the grout in the first place rather than relying on cleaning to remove it after the fact — a genuinely different mechanism from a standard grout sealer applied after installation. Combined with Ardex Grout Shield, built into the product to combat mould growth, it’s positioned to keep grout joints looking new for longer with less ongoing maintenance.
Technical Specifications
| Joint width | 1mm to 4mm |
|---|---|
| Location | Internal, external |
| Surfaces | Floors, walls |
| Colours | Multiple — see ARDEX website for full range |
| Packaging | 5kg (1.5kg and 20kg for Ultra White 390 only) |
Where to Use
- Polished porcelain and ceramic tiles
- Terrazzo, slate and quarry tiles
- Glass and moisture-insensitive natural stones
- Internal and external floors and walls
How to Apply
- Confirm tile compatibility — ensure the natural stone (if used) is not moisture sensitive.
- Mix the grout — combine per the packaging instructions to a smooth, workable consistency.
- Apply into joints — work the grout into 1-4mm joints using a rubber float.
- Clean the surface — remove excess grout before it fully cures, taking care not to scratch polished tile surfaces.
Important Notes
- Refer to the ARDEX website for the current colour range and coverage chart.
- Ultra White 390 is the only colour available in 1.5kg and 20kg pack sizes; other colours come in 5kg.
- For professional use.
The water-repellent hydrophobing agent in FS-DD works at the grout’s surface pores rather than as an applied topical sealer, which means the protection doesn’t wear off the way a sealer coating eventually does with foot traffic and cleaning. Combined with Ardex Grout Shield’s built-in mould resistance, that gives a genuinely lower-maintenance grout joint over the life of the installation, rather than one that needs periodic resealing to keep performing as intended. Choosing FS-DD over a standard sanded grout is really a decision made at the tile-selection stage, since it’s the polished porcelain itself that dictates the need for a fine, non-scratching grout in the first place.
