Description
Sika MonoTop-352 NFG is a lightweight, high-build structural repair mortar for damaged and spalled concrete, supplied here as a 20kg bag in grey powder form. It is a one-component, polymer-modified, fibre-reinforced mix with a built-in corrosion inhibitor, and it meets Class R3 of EN 1504-3. It suits both hand application and wet-spray machine application.
About the formula
The mortar is based on sulphate resistant cement, selected lightweight aggregates, a corrosion inhibitor and polymer modification. Sika describes it as low shrinkage, low permeability and sulphate resistant. The low density makes it easier to build up thickness while still being suitable for structural repair. On a well prepared, roughened substrate a bonding primer is generally not needed, even when applying by hand. It can also be used as a repair mortar before Sikagard 62 and 63N coatings, and it is compatible with the Sika FerroGard sacrificial anode system.
Where to use it
Indoors: repairing spalled or damaged concrete in buildings, including structural elements and superstructure works.
Outdoors: repairing concrete in bridges and other infrastructure, and restoring cover over reinforcement where concrete has been contaminated or carbonated.
Suitable for concrete repair, including restoration work and structural strengthening as set out in EN 1504-9. Layers can be built from 4mm up to 75mm in a single application.
How to use it
- Prepare the area first. Remove loose, contaminated and deteriorated material and clean any exposed reinforcement of rust, scale and dust. Roughen the substrate using abrasive blasting or high pressure water-blasting.
- Pre-wet the prepared substrate about 2 hours before application and keep it in a saturated surface dry (SSD) condition.
- Pour 2.8 to 3.3 litres of clean water into a suitable container for each 20kg of powder. Add the powder while stirring slowly. Mix thoroughly for at least 3 minutes, using a low speed drill mixer (under 500 rpm) or a forced-action mixer for machine application. Small amounts can be mixed by hand.
- Apply by trowel, pressing the mortar firmly onto the substrate, or by wet-spray equipment. Finish once the mortar begins to stiffen.
- Protect the fresh mortar straight away from premature drying using a suitable curing method, such as a curing compound, damp geotextile or polythene sheet.
Important notes
Apply only to sound, properly prepared substrate. Do not exceed the recommended water dosage, and do not add extra water while finishing, as this can cause discolouration and cracking. Avoid application in direct sun or strong wind, and protect freshly applied material from freezing. The recommended ambient and substrate temperature range for application is +5 °C to +30 °C. Final set is about 6 hours. For critical or structural repairs, follow the current Sika Product Data Sheet and the Sika method statement for concrete repair.
Specifications
| Brand |
Sika |
| Product |
MonoTop-352 NFG Structural Repair Mortar |
| Pack |
20kg bag |
| Colour |
Grey powder |
| Base |
Sulphate resistant cement, corrosion inhibitor, lightweight aggregates, polymer modified |
| Application |
Hand (trowel) or wet-spray machine |
| Layer thickness |
4mm minimum, 75mm maximum per layer |
| Mixing water |
2.8 to 3.3 litres per 20kg |
| Yield |
About 12.8 litres of mortar per 20kg |
| Consumption |
About 15.6kg of powder per cm thickness per m² |
| Fresh mortar density |
About 1.8 kg/l |
| Maximum grain size |
2mm |
| Final set |
About 6 hours |
| Standard |
Class R3 of EN 1504-3 |
| Shelf life |
12 months in unopened, undamaged packaging, stored dry and cool |
| Use |
Interior and exterior concrete repair |
Safety
This is a cement-based powder. Hazards include skin irritation, possible allergic skin reaction, serious eye damage and respiratory irritation. Avoid breathing dust, use in a well-ventilated area, and wear protective gloves and eye or face protection. Wash skin thoroughly after handling and do not wear contaminated work clothing out of the workplace. Refer to the Safety Data Sheet (SDS) for full details.
