FOX MULTISEAL® 1K FS365 is a cement-based, polymer-modified, single-component waterproofing material designed for application on all types of reinforced concrete surfaces and cement-based render surfaces. It delivers reliable waterproofing performance in vertical and horizontal applications, both indoors and outdoors.
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Product Description
FOX MULTISEAL® 1K FS365 is a single-component, cement-based waterproofing material composed of special cement, mineral fillers and polymer additives. It can be applied to reinforced concrete surfaces and cement-based render surfaces by brush, trowel or spray machine. Applied in two or three coats, the material forms a seamless and jointless, permanent waterproof layer. When applied at an ambient temperature of +23°C, it becomes waterproof after 7 days and reaches its final strength after 28 days. It is resistant to chemicals in soil and salt solutions, while maintaining water vapour permeability.
Key Benefits
- Its single-component formula provides ease of mixing and saves time during site preparation.
- Applicable by brush, trowel or spray machine, offering flexibility for different site conditions.
- Its non-shrinking and crack-resistant structure provides long-term, maintenance-free waterproofing.
- High adhesion strength (1.0 N/mm²) creates a reliable waterproof layer beneath screeds and ceramics.
- Wide service temperature range (-20°C / +80°C) enables use from cold storage facilities to wet rooms.
- Water vapour permeability allows the underlying structural layers to breathe.
Advantages
- Easy to prepare and apply.
- Can be applied by brush, trowel or spray machine.
- Long working time.
- Does not shrink or crack.
- High adhesion performance creates a waterproof layer beneath screeds and ceramics.
- Forms a seamless, jointless, permanent, waterproof coating.
- Resistant to chemicals in soil and salt solutions.
- Water vapour permeable.
Usage Areas
- In interior and exterior applications, on vertical and horizontal surfaces, from the water-facing side
- Foundation wall waterproofing
- Retaining walls
- All wet areas such as bathrooms and balconies
- Small terraces
- Small swimming pools and ornamental ponds
- Wall and floor coverings of cold storage facilities
- Planter box waterproofing
- Protection of concrete against water, carbonation and de-icing salts
- Water and balance tanks
Application Steps
- 1
Surface Preparation
The surface to be treated must be sound and free from oil, grease, rust, paraffin, paint and bitumen residues, with all loose particles removed. Iron and wooden plugs on the surface must be removed, and active water leaks must be filled with FOX PLUG FC340. Voids, uneven surfaces and corner edges must be repaired with FOX MORTAR FC188 T repair mortar to a minimum radius of 4 cm. The surface must be dampened with water prior to application, but ponding must not be allowed.
- 2
Mixing
Add the appropriate amount of water to a clean mixing container. Add FOX MULTISEAL® 1K FS365 slowly while mixing with a high-speed electric mixer at 400–600 rpm. Mix for approximately 3–5 minutes until the mixture is homogeneous, allow to rest for 3–5 minutes, then mix for a further 1 minute to make it ready for application. For brush consistency, add 4.60 lt of water per 20 kg bag; for trowel consistency, add 3.80 lt of water.
- 3
Application
The prepared mixture is applied in two or three coats using a waterproofing brush. The direction of brush application for each coat must be perpendicular to the previous coat. The waiting time between coats is determined according to site conditions. The wet film thickness must not exceed 2 mm per coat. In hot weather or windy conditions, additional water equivalent to 10% of the product weight may be added to the mix for the first coat only.
- 4
Tool Cleaning
Tools and equipment used must be cleaned immediately with water after application.
Application should not be carried out if the ambient and surface temperature is below +5°C or above +25°C; suitable temperatures must be awaited.
Application should not be carried out in extremely hot, rainy or windy weather.
In exterior surface applications, the surface must be protected from sunlight, wind, rain or frost for the first 24 hours.
For the material to complete its curing, the ambient and substrate temperature must not fall below the permitted minimum temperature.
The wet film thickness in application must not exceed 2 mm per coat.
FOX MULTISEAL® FS478 should be used for pools, vibrating floors and surfaces expected to deflect.
Areas that need to be walked on should be covered with a screed containing FOX BINDER FM125 additive.
It is recommended to use INNO-FIX series ceramic adhesives when covering the surface with ceramic, marble or similar products.
Active water leaks must be repaired with FOX PLUG FC340, and voids, uneven surfaces and corner edges must be repaired with FOX MORTAR FC188 T repair mortar to a minimum radius of 4 cm.
The pot life of the fresh mix is 2 hours; it must be consumed within this time.
The product should be stored between +5°C and +30°C, away from direct sunlight, in a cool and dry environment. Shelf life is 12 months from the date of manufacture.
Opened packages should be tightly resealed, stored under appropriate conditions and used within one week.
Work clothing, protective gloves, goggles and a mask must be worn during application. In case of contact with skin or eyes, wash thoroughly with plenty of water and soap; if swallowed, seek medical attention immediately.
Storage and application areas must be ventilated; approaching with open flames is dangerous.
Must be stored out of reach of children. Food and beverages must not be brought into application areas.
The technical values above are given for +23°C and 50% relative humidity conditions. Higher temperatures shorten the time, lower temperatures extend it.
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