10 Best External Slate Sealer for 2025

SIKA

• Dries clear: Using a solvent free formula, Geo-Fix Stone Protector dries clear and will not stain or alter the colour of the substrate
• Utmost protection: Using enhanced Fluor-Resin formula, it provides an improved shield protecting from liquid stains such as oil, petrol, water and much more
• Prevents future damage: Prevents destruction on the substrate from water penetration and erosion
• Drying time: 5–7 hours depending on the weather condition
• Release coat for chewing gum: Provides better release coat, making the removal of chewing gum from substrates much easier
• Internal and external use: Can be used on both interior and exterior substrates such as floor tiles, slates, marble, block paving and much more
• Maintains substrate appearance: Does not affect or alter the substrates colour or appearance once applied
• Available in 1 Litre and 5 Litre

SIKA

• Quick curing time: Rapid two-in-one, easy to use, high grab adhesive and sealant that is skin time' 70 minutes, curing ~3 mm per 24hours
• Instant high grab adhesive: High strength adhesion and non-slip properties that bonds to most common building substrates including brick, metals, concrete etc.
• Permanent elastic seal: Long-lasting flexible and elastic seal suitable for filling and sealing internal and external cracks
• Exterior and interior uses: Ideal for bonding mirrors to most common surfaces, sealing vertical expansion joints, jointing cladding panels and much more
• Available in grey, brown, black, white and beige

Sika

• Usage: Formulated as an alternative to mortaring lead flashing and sheet into brick, stone, concreate also suitable for sealing copper and zinc
• Finish: Provides a fully waterproof flexible joint that will not crack, Shrink, stain or corrode soft metals unlike most conventional Sealants
• Temperature resistance: Suitable for low and high temperatures up to 150 degrees Celsius
• Benefit: Provides a quicker, cleaner and easier join than using cement mortar
• Certification: Certified to the European Standard EN15651 for façade use internally in compliance with the Construction Product Regulation

LTP

• Environmentally friendly water based impregnating sealer.
• Moisture-repellent and stain resistant.
• Delicately enhances appearance.
• Helps prevent moss and mould formation.
• Coverage: 37.5m² to 75m² per 5 litres, depending on porosity.

Sika

• Quick Curing Time: Rapid two in one, easy to use, high grab adhesive and sealant that is touch dry within 30 minutes
• Instant High Grab Adhesive: Using hybrid polymer technology Stixall takes the features of silicone and polyurethane to form the incredible high strength, high grab, primerless adhesive
• Exterior and Interior Uses: Ideal for bonding mirrors to most common surfaces, automotive gap filing and sealing, jointing cladding panels and much more
• Multifunctional: High instant grab adhesion to most internal and external surfaces including glass, metals, plastic, concrete, plasterboard, polyester, Perspex, wood, enamel, painted surfaces and much more
• Paintable: Once fully dried this product can be overpainted
• Available in black, white, crystal clear, grey, brown and natural

Smartseal

Ronseal

• Thompson's Patio & Block Paving Seal offers advanced protection for paving
• It seals and protects against dirt and chemicals and resists penetration of oils and fuels
• Contains effective biocide to resist moss and algal growth

SIKA

• Quick Curing Time: Rapid, easy to use water seal that drives within 1 hour
• Dries Clear: Using a solvent free formula, 402 dries clear and will not stain the substrate
• Multi-Substrate: Suitable for use on most common substrates including brick, stone, concrete, pebbledash, rendering and much more
• Anti-Mould Formula: Repels waterborne dirt and resists fungal growth on substrates
• High Strength: Using the latest technology in silicone resin, waterseal form an utmost high strength and high performing water repellent that protects against damaged caused from mould and weather

LTP

• Environmentally friendly water based impregnating sealer.
• Moisture-repellent and stain resistant.
• Delicately enhances appearance.
• Helps prevent moss and mould formation.
• Coverage: 7.5m² to 15m² per litre, depending on porosity.

Tile Rite

• Maximum protection against oil & water based stains
• Hard wearing gloss finish
• Interior & exterior use
• UV resistant will not yellow
• Coverage up to 15m2 Per Litre