When structural concrete and steel repairs demand reliability in the most challenging conditions, Megapoxy H delivers. This low-viscosity, hydrophilic epoxy resin handles critical bonding, crack repair, and high-strength mortar applications, even in potable water or submerged environments. It ensures durability and compliance where other solutions fall short.

Why this product exists

Megapoxy H is engineered as a low viscosity, 100% solids, solvent-free, hydrophilic epoxy resin. It provides robust structural repair, bonding, and high-strength mortar solutions. This formulation addresses the need for materials that maintain integrity in critical environments, including contact with drinking water and exposure to aggressive chemicals like hydrogen sulphide. It establishes strong, permanent bonds between new and old concrete, repairs cracks, and is suitable for underwater and splashzone applications.

The numbers that matter

• Mixed Viscosity of 800 cps: This low viscosity allows Megapoxy H to penetrate deeply into fine concrete cracks, restoring structural integrity where higher viscosity epoxies cannot reach. It also ensures easy mixing and flow for pouring and injection applications.
• Ultimate Compressive Strength of 120 MPa: When cured, Megapoxy H achieves a compressive strength significantly superior to most concrete. This means it reinforces and strengthens the substrate, ensuring repairs are not the weakest link in the structure.
• Tensile Bond Strength to Steel of 18 MPa: For anchoring steel into concrete, this high bond strength ensures secure fixation of rebar or bolts, resisting significant pull-out forces. The bond strength to concrete is rated at >3 MPa, indicating the concrete will fail before the bond does.
• 100% Solids and Very Low VOC (2 g/l): Its 100% solids content means no shrinkage upon curing, ensuring a full, permanent bond. The very low volatile organic compound content contributes to safer application environments, particularly in enclosed spaces.

What it's like to use

Megapoxy H requires precise mixing at a ratio of 3 parts A to 1 part B by volume. Thorough mixing for a minimum of three minutes is critical for optimal performance. Once mixed, it offers a 30-minute work time at 25°C, allowing sufficient time for placement, pouring, or injection. Minimum application temperature is 10°C.

Surface preparation is key for maximum adhesion. Concrete surfaces must be clean, free from grease, oil, and laitance. Mechanical abrasion (scabbling, grit blasting, or grinding) is preferred. If not possible, acid etching can be used, followed by thorough washing and 24 hours of drying. Metal surfaces require grit blasting to AS 1627.2.2002 or mechanical abrasion to a clean, bright finish, followed by degreasing. All existing coatings should be removed to ensure superior bond strength. For cleaning tools and implements, use Megapoxy Thinners.

Where this product excels

• Concrete — Membrane Covered, Tiled: For crack injection and filling larger cracks in concrete slabs under membrane-covered or tiled finishes, ensuring a stable substrate for subsequent layers.
• Plant Rooms, Lift Motor Rooms, Commercial Internal Areas: Utilised as a primer before epoxy floor coatings or as a coving material, providing a durable, chemical-resistant base in high-traffic, internal environments.
• Civil Construction and Potable Water Infrastructure: Ideal for structural repairs within drinking water systems, such as reservoirs and pipelines, due to its AS/NZS 4020:2018 compliance for contact with potable water. It resists hydrogen sulphide, making it suitable for wastewater treatment plants.
• Underwater and Splashzone Repairs: Its hydrophilic nature allows for strong, permanent bonds on damp substrates and maintains excellent mechanical properties in submerged or splashzone conditions for marine and civil applications.

How it fits in a real system

Megapoxy H frequently serves as an initial and critical step in comprehensive concrete repair systems. It is applied early in the sequence, either as a primer or for crack injection, establishing a strong foundation before subsequent layers. For example, in concrete repair, it acts as a primary bonding agent for new-to-old concrete or as the injection resin for structural crack repairs.

This product is often specified alongside companion products like coloured epoxy floor epoxy base coats in plant rooms, where it primes the concrete for trafficable epoxy finishes. For more extensive concrete patching, it can be paired with epoxy concrete patch rapid concrete repair paste or epoxy surface sealant joint band adhesive for detailing and capping cracks.

Choose this when

• When performing structural concrete and steel repairs: It delivers high compressive and tensile bond strengths, suitable for re-establishing load-bearing capacity.
• When AS/NZS 4020:2018 compliance is mandatory: Specifically for repairs in contact with potable water, ensuring no contamination.
• When repairing cracks in concrete: Its low viscosity allows deep penetration for crack injection via capillary action, low-pressure, or pressure injection methods, restoring structural integrity.
• When bonding new-to-old concrete, especially on damp substrates: Its hydrophilic properties ensure effective bonding even when the surface is not completely dry.
• When forming high-strength epoxy mortars: It can be mixed with fine aggregates to create pourable or trowelable mortars for durable floor repairs, grouting, or truncation pocket grouting.
• When repairs are subjected to hydrogen sulphide or submerged conditions: Its chemical resistance and performance in wet environments ensure longevity in aggressive wastewater or marine settings.

Don't use this when

• Not for: Horizontal steel anchoring. For this specific application, Megapoxy HT is the recommended product.
• Not for: Vertical or overhead new-to-old concrete bonding or rendering. Megapoxy HT is formulated for these overhead and vertical applications.
• Not for: Cracks expected to undergo further movement. This product is designed for static crack repair, restoring monolithic structural integrity.
• Not for: Applications without precise mixing. Incorrect mixing ratios or poor blending will lead to unsatisfactory cure and reduced physical properties.