Mapei Planitop Smooth and Repair R4 Zero

Mapei Smooth & Repair R4-class Zero is a rapid-setting fibre-reinforced structural cementitious mortar, applied in a single layer from 3 to 40 mm thick, for repairing and smoothing concrete.

Best Uses

Mapei Planitop Smooth and Repair R4 Zero is ideal for structural repairs and smoothing over internal and external horizontal and vertical concrete surfaces; suitable for repairing structures exposed to the open air and in permanent contact with water. This R4 class repair mortar is also suitable for the rapid repair work on deteriorated concrete beams, pillars, buffer walls, cornices, edges of balconies and structural members and elements that require the use of mortar with high mechanical performance characteristics.

Mapei Planitop Smooth and Repair R4 Zero is also ideal for:

• Quickly smoothing over surface defects in cast concrete, such as deep gravel clusters, spacer holes, second pours, etc. before painting the surface
• Repairs and structural strengthening of concrete
• Repairing precast concrete members and elements
• Repairs to concrete damaged by rusty reinforcing bars due to carbonation

Planitop Smooth & Repair R4 Zero is a one-component, thixotropic mortar made from special, highly reactive hydraulic binders, fine selected aggregates, synthetic polyacrylonitrile fibres, synthetic polymers and special admixtures according to a formula developed in the MAPEI Research Laboratories. Thanks to its particular formulation the product has excellent fatigue behaviour up to at least 300,000 cycles, which gives repaired structures a high level of resistance to cracking, including when subject to dynamic loads induced during normal service conditions.

This particular characteristic, together with the requirements of EN 1504, helps increase the durability of elements restored with Planitop Smooth & Repair R4 Zero. After mixing, the product forms a mortar with good workability and with setting and hardening times that can be modulated by adding Mapei Mapetard ES. It is applied by trowel in a single layer from 3 to 40 mm thick to repair and smooth over concrete. Planitop Smooth & Repair R4 Zero hardens without shrinking and is characterised by its excellent adhesion to concrete substrates.

Once hardened, Planitop Smooth & Repair R4 Zero has the following characteristics:

• Excellent adhesion to both old concrete (≥ 2 MPa), if wetted beforehand with water, and to steel reinforcement, especially when treated with Mapefer or Mapefer 1K Zero anti-corrosion and re-alkalising cementitious mortar, certified EN 1504-7 Corrosion protection of reinforcement
• High dimensional stability and, therefore, low risk of cracking and crazing during both the plastic phase and when hardened
• Thermal compatibility to freeze/thaw cycles, measured as adhesion according to EN 1542
• High resistance to carbonation
• Impermeable to water

Planitop Smooth & Repair R4 Zero is a product with very low emission of volatile organic compounds (VOC), which safeguards the health and safety of installers and final users. It is certified as EC1 Plus by the German association GEV. Planitop Smooth & Repair R4 Zero helps earn important LEED credits. Planitop Smooth & Repair R4 Zero complies with the principles defined in EN 1504-9 (Products and systems for protecting and repairing concrete structures: definitions, requirements, quality control and conformity assessment. General principles for the use of products and systems) and the minimum requirements of EN 1504-3 (Structural and non-structural repairs) for structural R4-class mortars and the requirements of EN 1504-2 coating (C) according to principles MC and IR (Concrete surface protection systems).

Application

Preparation of the substrate

Remove all deteriorated and loose concrete to form a sound, rough and strong substrate. Any areas previously repaired and which are not perfectly bonded must also be removed. After preparation, the surface of the substrate must be uneven with irregularities at least 5 mm deep. ▪ Remove all dust, rust, cement laitance, grease, oil and old paint from the concrete and reinforcement rods by sandblasting. Treat reinforcing bars with Mapefer or Mapefer 1K Zero according to the procedure illustrated in the relative data sheet for each product. Before applying Planitop Smooth & Repair R4 Zero wait until Mapei Mapefer or Mapei Mapefer 1K Zero are completely dry.

Saturate the substrate with water. Before carrying out repairs with Planitop Smooth & Repair R4 Zero, wait until any excess water has evaporated off. If necessary, use compressed air to help remove excess water. The substrate must be saturated with water but with a dry surface (s.s.d.).

Follow product data sheet for full preparation and application instructions.

Mapei Zero Range

Planitop Smooth & Repair R4 Zero is part of the CO Fully Offset in the Entire Life Cycle line of products. CO emissions measured throughout the life cycle of products from the Zero line in 2024 using Life Cycle Assessment (LCA) methodology, verified and certified with EPDs, have been offset through the acquisition of certified carbon credits in support of forestry protection projects.