In the world of construction, particularly when it comes to rehabilitation and repair, choosing the right material is of paramount importance. Among the many products available in the market, the Resistant Repair Mortar – Class R4 has been a top choice for many industry professionals. But what makes it so special?

  1. What is Resistant Repair Mortar – Class R4?

The Resistant Repair Mortar – Class R4 is a specific category of repair mortar, as defined by the EN 1504 Part 3 standard. This European Standard specifies performance requirements and describes test methods for structural and non-structural repair mortars. The R4 classification indicates that the mortar has a high compressive strength (greater than or equal to 45 MPa) and is ideal for use in demanding repair situations.

  1. Features and Benefits:

High Compressive Strength: As previously mentioned, Class R4 mortar boasts a compressive strength of ≥45 MPa. This makes it ideal for heavy-duty applications where high strength is paramount.
Excellent Durability: Due to its formulation, R4 repair mortar offers outstanding resistance to freeze-thaw cycles, ensuring longevity even in challenging climates.
Adhesion: One of the key factors in any repair work is how well the repair material adheres to the original substrate. Class R4 mortar exhibits excellent adhesion properties, ensuring a long-lasting bond.
Thermal Compatibility: The mortar has been formulated to accommodate thermal movements, ensuring that the repaired section doesn’t crack or delaminate due to temperature changes.
Shrinkage Compensation: Minimized shrinkage is another advantage, which reduces the risk of cracks forming as the mortar sets and hardens.

  1. Applications:

Given its features, the Resistant Repair Mortar – Class R4 finds application in various areas:

Structural Repairs: Ideal for repairing beams, columns, and other structural elements, particularly in high-load areas.
Overhead and Vertical Repairs: Due to its excellent adhesion properties, it’s suitable for use in overhead and vertical applications without sagging.
Marine Environments: Given its resistance to chloride ingress and freeze-thaw cycles, it’s a suitable choice for repairs in marine environments or structures exposed to de-icing salts.

Working with Resistant Repair Mortar – Class R4 and its Variants:

While the Class R4 mortar offers numerous advantages, it’s imperative to adhere to manufacturer guidelines during application. Ensuring the substrate is clean, devoid of loose materials, and properly pre-wetted is crucial. Depending on the product you’re using, some may necessitate a primer or bonding agent for optimal performance. For instance:
FIXATIV C75 by DC INDUSTRIES: This is a variation of the R4 repair mortar, tailored with specific additives to enhance performance and workability. Adhering to DC INDUSTRIES’ application guidelines will ensure optimal results when using this product.
FIXATIV B22 by DAST: Another variant in the repair mortar category, FIXATIV B22 is designed for specific repair scenarios, offering unique properties that might differ from standard R4 mortars. Always refer to DAST’s product data sheet and application instructions to make the most of its features.
It’s also of paramount importance to cure the mortar adequately post-application, irrespective of the brand or variant, to achieve its full strength and durability benefits.