Sika MonoTop®-108 Water Plug IN – Complete Industrial Description

Product Name: Sika MonoTop®-108 Water Plug IN
Product Type: Rapid-Setting Waterproof Cement Mortar
Chemical Base: Cement and Special Additives
Appearance: Lump-free Grey Powder
Application: Instant Water Leakage Sealing & Waterproofing
Brand: Sika

Sika MonoTop®-108 Water Plug IN is a ready-to-use, rapid-setting, waterproof cement mortar specially developed for instantly stopping water leakage through concrete and masonry structures. It is designed to provide fast and reliable sealing against water infiltration, including leakage occurring under negative water pressure.

The product is particularly suitable for sealing cracks, gravel pockets, casting joints, drainage outlets, water tanks, basements, sunken pits, and other concrete or masonry structures where rapid water-stopping performance is required.

Sika MonoTop®-108 Water Plug IN requires only the addition of clean water before application. Its rapid-setting characteristics allow the mortar to harden within approximately 2–3 minutes at +27 °C, helping prevent the material from being washed out even when applied in the presence of running water.

Product Composition and Structure

Sika MonoTop®-108 Water Plug IN is a cement-based waterproof plugging mortar formulated with cement and special additives. The formulation is designed to develop rapid setting and early strength after mixing with water.

Chemical Base:

Cement and Special Additives

Physical Form:

Lump-free Grey Powder

When mixed with the recommended quantity of water, the dry powder forms a workable mortar that can be quickly moulded and pressed into prepared leakage points. The rapid-setting characteristics allow the material to form an effective plug before significant washout can occur.

Key Properties

Sika MonoTop®-108 Water Plug IN offers several important properties for construction and waterproofing applications:

• Rapid setting and hardening
• Helps stop water leakage quickly
• Suitable for areas with running water
• Ready to use—only water needs to be added
• Quick strength development
• Waterproof cement mortar
• Non-toxic and chloride-free
• Excellent adhesion to concrete and masonry
• Good adhesion to metals, PVC and HDPE
• Low exothermic reaction
• Coefficient of thermal expansion similar to concrete
• Helps minimise the risk of thermal cracking
• Suitable for negative water pressure leakage
• Suitable for vertical and horizontal leakage-sealing applications

These characteristics make Sika MonoTop®-108 Water Plug IN a practical solution for emergency and rapid water-leakage sealing in concrete and masonry structures.

Working Principle

Sika MonoTop®-108 Water Plug IN works primarily through rapid cementitious setting and hardening.

After mixing the powder with the recommended quantity of clean water, the mortar is quickly moulded into a plug and pressed firmly into the prepared leakage point. The mortar rapidly develops its initial set, allowing it to remain in position and resist washout from running water.

At approximately +27 °C, the product has an initial setting time of around 150 seconds and a final setting time of around 200 seconds, although actual setting time can vary depending on product, water, substrate and ambient temperatures as well as the amount of water used.

Major Applications

Concrete Water Leakage Sealing

Sika MonoTop®-108 Water Plug IN is designed for instantly sealing water leakage through concrete structures. It can be used around cracks, casting joints and localised leakage points.

Masonry Waterproofing

The product can be used to seal water infiltration through masonry walls and other mineral-based substrates.

Water Tanks

It is suitable for sealing leakage points encountered during waterproofing work in water tanks and similar structures.

Basements and Sunken Pits

Basements, sunken pits and below-ground structures can experience water infiltration due to groundwater pressure. Sika MonoTop®-108 Water Plug IN can be used for rapid sealing of localised leakage points.

Drainage Outlets

The product can be used for instant sealing of water drainage outlets during waterproofing treatments.

Cracks and Casting Joints

It can be used to seal negative-pressure water leaks through cracks, gravel pockets and casting joints.

Injection Grouting

Sika MonoTop®-108 Water Plug IN can also be used as a plugging mortar for fixing nozzles and grouting ports during injection-grouting works.

Advantages

Sika MonoTop®-108 Water Plug IN provides several advantages for professional waterproofing and repair applications:

• Rapid Setting: Hardens within approximately 2–3 minutes at +27 °C.
• Water Leakage Control: Designed specifically for rapid plugging of water leakage.
• Running Water Application: Rapid setting helps prevent washout in the presence of running water.
• Easy Application: Ready-to-use powder requiring only clean water.
• Early Strength: Develops strength rapidly after application.
• Excellent Adhesion: Bonds well to concrete, masonry and several other materials.
• Chloride-Free: Formulated without chloride.
• Low Exothermic Reaction: Helps reduce the risk of thermal cracking.
• Wide Application Range: Suitable for concrete, masonry and waterproofing-related works.

Technical Parameters (Typical)

Property	Typical Value
Product Type	Rapid-setting waterproof cement mortar
Chemical Base	Cement and special additives
Appearance	Lump-free grey powder
Packaging	1 kg pouch / 5 kg bag
Shelf Life	12 months
Fresh Mortar Density	~2.1 kg/L
Initial Setting Time	~150 seconds at +27 °C
Final Setting Time	~200 seconds at +27 °C
Compressive Strength – 6 hours	~8 N/mm²
Compressive Strength – 24 hours	~10 N/mm²
Water Requirement – 1 kg	0.26–0.28 L
Water Requirement – 5 kg	1.30–1.40 L
Ambient Temperature	+10 °C to +40 °C
Substrate Temperature	+10 °C to +40 °C

The above values are typical technical values published by Sika India and may vary depending on site conditions, temperature, water-to-powder ratio and application conditions.

Mixing and Application

Sika MonoTop®-108 Water Plug IN is designed for rapid application. Because of its fast setting characteristics, only a small quantity should normally be mixed at a time.

Basic Mixing Procedure:

1. Pour a small quantity of clean water into a suitable mixing container.
2. Add the required quantity of Sika MonoTop®-108 Water Plug IN powder.
3. Quickly mix the powder and water to form a mortar.
4. Mould the mortar into a plug using a suitable gloved hand or tool.
5. Immediately press the mortar firmly into the prepared leakage point.
6. Maintain pressure until the mortar has sufficiently set.
7. Remove excess material after sealing is complete.

Sika recommends preparing the leakage area by mechanically cleaning it and removing loose particles, laitance, oil, grease and other contaminants. For leakage points, the area can be widened and deepened in a dove-tail configuration to approximately 20 mm to provide sufficient space for the plugging mortar and improve bonding.

Water Mixing Ratio

The recommended water requirement according to Sika India is:

For 1 kg pouch: Approximately 0.26–0.28 litre of water

For 5 kg bag: Approximately 1.30–1.40 litres of water

The exact quantity may be adjusted according to site conditions and the consistency required. Excess water should be avoided because the setting characteristics and performance can be affected by the water-to-powder ratio.

Compressive Strength

Sika MonoTop®-108 Water Plug IN develops strength rapidly after application.

Typical compressive strength values are:

• 6 hours: Approximately 8 N/mm²
• 24 hours: Approximately 10 N/mm²

These values are measured according to ASTM C109 under the conditions specified in the Product Data Sheet.

Suitable Substrates

Sika MonoTop®-108 Water Plug IN can be used on a variety of construction substrates, including:

• Concrete
• Cementitious surfaces
• Masonry
• Brickwork
• Mineral substrates
• Metals
• PVC
• HDPE

Its good adhesion characteristics make it suitable for sealing leakage points involving different construction materials.

Packaging

Sika MonoTop®-108 Water Plug IN is supplied in:

• 1 kg pouches
• 5 kg bags

The product should remain in its original, unopened and undamaged packaging until use.

Storage Conditions

For maintaining product quality, Sika MonoTop®-108 Water Plug IN should be stored:

• In a cool and dry location
• In unopened original packaging
• Protected from moisture
• Protected from frost
• Away from direct sunlight
• At temperatures between +10 °C and +35 °C

The stated shelf life is 12 months from the date of production, provided the product is stored under the recommended conditions.

Safety and Handling

Although Sika MonoTop®-108 Water Plug IN is designed for construction applications and is described as non-toxic and chloride-free, normal precautions for handling cement-based powders should be followed.

Safety Precautions:

• Avoid breathing dust during handling and mixing.
• Use suitable protective gloves.
• Wear appropriate eye protection.
• Ensure adequate workplace ventilation.
• Avoid unnecessary contact with eyes and skin.
• Follow the manufacturer’s Safety Data Sheet and site safety procedures.
• Wash hands and exposed skin after handling.

Because the mortar sets rapidly, operators should prepare only the quantity that can be applied immediately.

Cleaning of Tools

All tools and application equipment should be cleaned with water immediately after use.

Once the material has hardened, it can generally only be removed mechanically.

Important Application Considerations

Sika MonoTop®-108 Water Plug IN is a rapid-setting plugging mortar, not a general-purpose waterproofing coating. It is primarily intended for sealing localised water leakage points.

When water pressure is excessive, Sika recommends reducing the water pressure where appropriate and addressing the main leakage point before sealing secondary openings. Multiple applications may be required where leakage pressure is high.

Suitable Construction Areas

Sika MonoTop®-108 Water Plug IN can be particularly useful in:

• Basement waterproofing
• Water tank waterproofing
• Sunken pit waterproofing
• Concrete repair
• Masonry repair
• Underground structures
• Leakage sealing
• Drainage outlet sealing
• Injection grouting preparation
• Construction joint leakage treatment
• Crack leakage treatment
• Below-ground waterproofing works

Why Choose Sika MonoTop®-108 Water Plug IN?

Sika MonoTop®-108 Water Plug IN combines rapid setting, early strength development, adhesion and water-stopping capability in a ready-to-use cementitious mortar.

Its ability to harden rapidly in the presence of running water makes it particularly valuable for situations where conventional cement mortar may be washed away before it can set. The product can therefore provide a fast solution for localised water leakage in concrete and masonry structures.

Its ready-to-use formulation also simplifies site application because the installer only needs to add the recommended amount of clean water before forming and pressing the mortar into the leakage point.

Conclusion

Sika MonoTop®-108 Water Plug IN is a professional rapid-setting waterproof cement mortar designed for instantly stopping water leakage in concrete and masonry structures. Its rapid setting characteristics, early strength development, excellent adhesion and resistance to washout make it a practical solution for emergency water-leakage sealing and waterproofing-related construction work.

It is suitable for cracks, gravel pockets, casting joints, drainage outlets, water tanks, basements, sunken pits, concrete and masonry structures, as well as for fixing nozzles or grouting ports during injection-grouting applications.

With its simple add-water-and-apply formulation and rapid hardening performance, Sika MonoTop®-108 Water Plug IN provides an efficient solution for professional contractors, waterproofing specialists and construction professionals who require fast and reliable water-stopping performance.