Ardex K 301 Exterior Self Smoothing Levelling Compound 25kg
Ardex K 301 Exterior Self Smoothing Levelling Compound 25kg
- Fast setting - walkable after 2-3 hours
- Rapid hardening can withstand light vehicular traffic after 48 hours
- Easy to mix and apply pumpable
- Apply from 2mm to 20mm thick in a single application
- Can be used with suitable resin coatings
- Suitable for internal and external applications
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| Type | Screeds-Levellers |
|---|---|
| Brand | Ardex |
| Coverage | Approximately 7.8m2 at 2mm thick per 25kg bag. |
| Size | 25KG |
ARDEX K 301 Exterior Self-Smoothing Levelling and Resurfacing Compound
ARDEX K 301 is a high-performance, fast-setting, cement-based levelling and resurfacing compound designed to smooth and restore rough or damaged concrete surfaces. Ideal for both internal and external applications, this versatile product delivers a durable, flowable mortar that creates a flat, smooth finish for a variety of concrete surfaces, including driveways, patios, walkways, balconies, and garage floors. Its rapid hardening properties make it an excellent choice for projects requiring quick turnaround times without compromising strength or qualit
Key Features
- Fast-Setting Formula: Sets within approximately 1-2 hours and is walkable in just 2-3 hours at 20°C (68°F), minimizing downtime.
- Rapid Hardening: Ready to support light rubber-wheeled vehicular traffic after 48 hours, ensuring durability for demanding environments.
- Flexible Application Thickness: Can be applied from 2mm to 20mm in a single layer, accommodating a range of surface irregularities.
- Self-Smoothing: Produces a fluid mortar that flows easily, reducing the need for extensive troweling and ensuring a consistent finish.
- Internal and External Use: Suitable for a variety of environments, including permanently wet areas like swimming pools, where it can be tiled directly.
- Pumpable: Simplifies large-scale applications, making it efficient for projects like parking areas, courtyards, and commercial floors.
- Crack-Resistant: Engineered to minimize cracking, providing a stable base for further finishes or coatings.
- Compatible with Coatings: Can be sealed, painted, or coated with suitable resin-based systems, such as ARDEX WPM 200, for enhanced protection.
Surface Preparation
For optimal results, surfaces must be properly prepared:
- Concrete should be mature (at least 6 weeks old), hard, sound, and free of oil, grease, curing compounds, or other contaminants.
- Substrate can be dry or damp but not wet.
- Cracks should be repaired using a suitable crack repair system, such as ARDEX P10 SR, to prevent telegraphing.
- Movement joints must be carried through to the surface to prevent cracking
- Priming is required: Internal Dry Areas: Use ARDEX P51 Primer diluted 1:1 with water for absorbent surfaces or 1:0.5 for non-absorbent surfaces. External or Damp Areas: Dilute ARDEX P51 Primer 1:7 with water. Remove excess primer to avoid incorporation into the mortar.
Application Guidelines
- Mix ARDEX K 301 with clean water (5 liters per 25kg bag) to achieve a lump-free, fluid consistency.
- Pour the mixed mortar onto the primed surface within its 30-minute working time.
- Spread using a steel trowel, float, or gauging tool for larger areas. The mortar will self-smooth within the first 10 minutes.
- For a non-slip finish, reduce water content slightly and apply a broom finish after initial set (~40 minutes).
- Protect the fresh surface from rapid drying, direct sunlight, frost, or strong drafts until fully hardened.
- For multi-layer applications, sand the first layer (16-36 grit), clean, prime, and allow it to fully harden before applying the next.
Limitations
- Not suitable for heavy-duty industrial floors, public highways, or surfaces subject to metal or solid-wheeled traffic.
- Avoid use on asphalt, tarmacadam, or frost-damaged concrete prone to deflection.
- Not recommended for areas with intensive abrasive use in wet conditions.
- Apply at temperatures above 5°C (41°F).
Why Choose ARDEX K 301?
ARDEX K 301 combines speed, versatility, and durability, making it a trusted solution for contractors, builders, and homeowners. Its ability to deliver a smooth, hard-wearing surface in just hours sets it apart for time-sensitive projects, while its compatibility with wet environments and various finishes ensures long-lasting performance. Whether you’re resurfacing a weathered driveway or preparing a poolside area for tiling, ARDEX K 301 provides a cost-effective, reliable foundation for your project.
Coverage: Approximately 7.8m2 at 2mm thick per 25kg bag.
Technical Details
| Working Time (20°C) | ~30 min |
|---|---|
| Initial Set | Approximately 40 minutes |
| Final Set | Approximately 2 hours |
| Tensile Bending Strength | 6.5 N/mm² after 28 days |
| Application depth | 2-20mm |
| Working time | 30 minutes |
| Walk on time | After 2-3 hours |
| Light traffic from | 48 hours |
| Bulk density of powder | approx. 1.37kg/litre |
| Coverage | 3m² at 5mm per bag 7.8m² at 2mm per bag |
ARDEX K 301 Exterior Self Smoothing Levelling Compound – 25kg
ARDEX K 301 is a high-performance, cement-based self smoothing levelling and resurfacing compound designed for both internal and external floor preparation. It creates a strong, level and smooth surface prior to tiling or final floor finishes, making it ideal for professional installers and renovation projects.
With rapid hardening properties and excellent flow characteristics, K 301 helps speed up installation while maintaining surface strength and durability.
Key Features & Benefits
- Internal & External Use – Suitable for exterior and interior floor levelling applications.
- Self Smoothing Formula – Produces a flat, even surface with minimal trowel marks.
- Rapid Hardening – Speeds up floor preparation and reduces downtime.
- High Strength Performance – Designed for demanding site conditions.
- Ideal Subfloor Preparation – Perfect base for tiles and compatible floor finishes.
Typical Applications
ARDEX K 301 is commonly used when searching for solutions such as “exterior levelling compound”, “self levelling mortar”, or “concrete resurfacing compound”.
- Levelling uneven concrete substrates
- Smoothing cement/sand screeds before tiling
- Resurfacing worn or pitted floor areas
- Preparing floors for tile adhesive installation
- External thresholds and entrance areas (with correct preparation)
Technical Specifications
| Product Name | ARDEX K 301 Exterior Self Smoothing Levelling Compound |
|---|---|
| Pack Size | 25kg |
| Application Type | Self smoothing levelling & resurfacing compound |
| Suitable Areas | Internal & External floors |
| Substrates | Concrete and cement-based screeds (prime as required) |
| Colour | Grey |
| Brand | ARDEX |
Installation Guidance
- Ensure substrate is sound, clean and free from dust, oil and contaminants.
- Apply suitable primer depending on absorbency of the surface.
- Mix using a mechanical paddle mixer to achieve smooth consistency.
- Pour and spread evenly — product will self smooth to form level finish.
- Protect from frost, rapid drying and adverse weather conditions.
Recommended Accessories
- Compatible floor primers
- Spiked roller for de-airing
- Tile adhesive & grout for final finish
Frequently Asked Questions
Do I need to use a primer before applying ARDEX K 301?
Yes. Priming is recommended to improve adhesion and control surface suction. Always select primer suitable for your substrate type.
Can this be used externally?
Yes, ARDEX K 301 is suitable for external use when applied correctly and protected from extreme weather during curing.
When can I tile over it?
Tiling can commence once the compound has sufficiently hardened. Refer to manufacturer guidelines for specific drying times.
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