STEICOmulti Fill - Joint Adhesive & Repair Sealant - 310ml

STEICOmulti Fill is a high-performance, one-component sealing and adhesive mass. It is engineered specifically for use with wood-fibre insulation boards, acting both as a flexible filler for gaps and as a powerful adhesive for small repairs or specialist detailing like window sill installations. It is the specialist joint adhesive and sealant designed to ensure the integrity of your insulation envelope. While the boards provide the thermal mass, STEICOmulti Fill is what makes the system seamless and robust, particularly in External Thermal Insulation Composite Systems (ETICS).

CHARCTERISTICS

• Unlike standard fillers that may crack as a building moves, Multi Fill remains elastic. This allows it to absorb the natural expansion and contraction of timber and wood-fibre boards without losing its seal.
• Once cured, the sealant can be rendered or plastered over directly. It is designed to bond perfectly with the basecoat of the STEICOsecure render system, ensuring no shadowing or cracking appears in the final finish.
• It is highly resistant to UV radiation and can be applied wet on wet, making it ideal for the unpredictable British weather where surfaces might not be perfectly bone-dry during installation.
• In keeping with Steico’s ecological focus, Multi Fill is free from solvents, silicones, and isocyanates. It is virtually odourless and safe for both internal and external use.
• While flexible, it is robust enough to maintain the structural continuity of the insulation layer, preventing soft spots in the facade.

APPLICATION

• Used to seal joints in STEICO Protect or Universal boards where the gap is between 2mm and 6mm. This prevents thermal bypassing and protects the structure from moisture ingress.
• Ideal for bonding small fitting pieces or off-cuts of wood fibre back into a main board to ensure a continuous insulation layer.
• It is the designated adhesive for bonding the STEICOfix window sill wedges into place, ensuring a watertight connection at the most vulnerable part of the window opening.
• Sealing around service penetrations (pipes or cables) where they pass through wood-fibre boards.