Mapei Keracolor FF Bioblock Grout

For interior and exterior floor and wall tiling up to 6 mm wide, Keracolor FF Bioblock Grout provides a water-repellent, inhibits mould cementitious joint that protects smooth, polished, and standard ceramic surfaces from water ingress and fungal growth. This CG2WA classified grout is formulated for jobs ranging from domestic bathrooms and swimming pools to high-traffic commercial floors where chemical resistance is not required.

Water-repellent and inhibits mould technology

This polymer-modified grout uses special hydrophobic additives to achieve two specific physical mechanisms. DropEffect technology reduces the surface absorption of water, causing droplets to bead on the surface rather than penetrate the joint. This is paired with BioBlock technology, which inhibits the growth of mould and mildew in humid conditions, keeping the smooth final joint clean and sanitary. For extreme service conditions like external facades, bathrooms with heavy use, or high-traffic commercial floors, the grout can be mixed with Fugolastic synthetic resin additive instead of water to increase bond strength, density, and flexibility.

Numbers that matter

• Up to 6 mm joint width: Fine aggregate grading ensures a smooth, crack-free finish in narrow joints without scratching pre-polished marble, glazed tiles, or polished porcelain.
• CG2WA ISO 13007-3 classification: High-performance cementitious grout (CG2) with reduced water absorption (W) and high abrasion resistance (A) to withstand consistent floor cleaning and foot traffic.
• 2-hour pot life: Generous working window at +23°C allows the installer to mix full batches and secure complex glass mosaic or natural stone layouts before setting begins.
• 24-hour light foot traffic window: Fast initial cure allows subsequent trades onto the floor within one day of application, with full service readiness and pool filling achieved after 7 days.
• 26% to 30% water-to-powder mix ratio: Highly sensitive water window (26% to 28% for walls, 27% to 30% for floors) to ensure colour consistency and prevent surface efflorescence.

Where to use it

• Residential and commercial tiling: Suitable for single-fired, double-fired, klinker, porcelain, and glazed tiles.
• Stone and mosaics: Ideal for natural stones, marble, granite, agglomerates, and glass or marble mosaics.
• Wet areas and pools: Formulated for domestic bathrooms, showers, commercial wet areas, and swimming pools.
• Dry industrial floors: Suitable for garages, warehouses, and industrial floors where chemical resistance is not required.

Limitations

• Do not use in expansion or movement joints; these must be filled with a flexible MAPEI sealant.
• Do not use in swimming pools disinfected via saline electrolysis; use Ultracolor Plus or Kerapoxy for these installations.
• Do not mix with dry cement, other grouts, or different colours, and never add water to a mix that has begun to set.
• Do not apply in temperatures below +5°C or above +35°C.
• Never use acid cleaners like Keranet on marble, limestone, or other acid-sensitive natural stone materials.
• Rough or micro-porous tiles must be sample-tested for cleanability before grouting, and treated with a protective sealer if required.

How to apply

Ensure tile adhesive has completely hardened before grouting. Clean joints to at least 2/3 of the tile thickness to prevent adhesive show-through. When working in hot, windy conditions or with very porous ceramic tiles, wet the joints with clean water beforehand. Mix Keracolor FF with a low-speed mixer to prevent air bubbles, wait 2 to 3 minutes, and re-stir briefly before application. Pack the joints completely using a MAPEI float or rubber trowel, moving diagonally to remove excess material while fresh. When the mix becomes matt (typically 10 to 20 minutes), clean the tiles with a damp hard cellulose sponge, rinsing frequently in separate clean water buckets. For hot, dry, or windy environments, wet-cure the joints with clean water after several hours to achieve maximum physical strength.