Screeds

Use Ardex A 38 for: Creating custom high-strength screeds, fast-tracking tile installations, and building heated floor systems. Ardex A 38: A Technical Overview Ardex A 38 is a specialist rapid-set engineered cement for the professional tiler who requires ultimate control and performance. Unlike premixed screeds, Ardex A 38 is a...

Ardex A 38: A Technical Overview

Ardex A 38 is a specialist rapid-set engineered cement for the professional tiler who requires ultimate control and performance. Unlike premixed screeds, Ardex A 38 is a high-performance binder that you combine with ARDEX Gravel Mix on-site. This provides the flexibility to create a custom, high-strength screed tailored to your project's specific needs. Featuring ARDURAPID technology, it produces a dimensionally stable screed that dries fast and resists shrinkage, providing a reliable foundation that prevents tile lippage and cracking. It's the professional's choice for bonded, unbonded, and heated screeds in both internal and external environments.

8 Hours

Ready for tiles, natural stone, and terrazzo, allowing you to move from screeding to setting in the same day.

Core Features & Specifications

Rapid Hardening Formula: Walkable in 8 hours and ready for tiling just 8 hours after application, massively accelerating project completion.
Engineered Cement Binder: Gives you full control over the screed mix when combined with ARDEX Gravel Mix, perfect for specialised or large-scale applications.
Dimensionally Stable: ARDURAPID technology ensures minimal shrinkage and stress during curing, preventing cracks and ensuring a flat, stable substrate.
Exceptional Strength: Achieves a compressive strength of approximately 35 MPa and tensile bending strength of 5.0 MPa after 28 days for a highly durable finish.
Versatile System: Ideal for creating bonded, unbonded, and heated screeds for any internal or external tiling job.
Excellent Working Time: Provides up to 60 minutes of working time, allowing for proper application, compaction, and finishing without rush.

The Ardex A 38 Advantage for Tilers

Professional Performance: Control the mix, control the job. Ardex A 38 puts you in charge of the screed, ensuring the performance meets your high standards.
Reliability Through Chemistry: The advanced binder technology guarantees a fast, reliable cure with minimal shrinkage, so you can stand behind your work with confidence. No more callbacks for cracked screeds.
Innovation for Efficiency: The ability to tile after just 8 hours transforms your workflow, letting you complete multi-stage jobs faster and more profitably.
System Compatibility: Designed to work seamlessly with ARDEX primers and waterproofing systems, creating a fully integrated and warranted flooring system from a trusted name.

Proactive Troubleshooting for Tilers

Scenario: Incorrect aggregate or mix ratio

Potential Outcome: Using the wrong sand or an incorrect cement-to-aggregate ratio can severely compromise the screed's strength, cure time, and stability, leading to total system failure.

Adheseal Best Practice: Ardex A 38 is a high-performance system. Always use the specified ARDEX Gravel Mix (0-4mm) at the correct 1:5 ratio (20kg A 38 to 100kg gravel). This guarantees the engineered performance and rapid-set properties.

Scenario: Insufficient compaction during application

Potential Outcome: A poorly compacted screed will have voids, leading to low strength, an uneven surface, and potential for crumbling under load, causing tiles to crack or debond.

Adheseal Best Practice: Ensure the screed mix is thoroughly compacted and levelled during application. For thicker screeds, apply in layers no more than 50mm at a time, ensuring proper compaction between each layer to achieve a dense, solid finish.

Applications in Practice: Tiler & Waterproofer Scenarios

For Tilers: Large Format Commercial Floor

The Tiler's Challenge

A large commercial space requires a new, perfectly flat screed to accommodate 1200x600mm porcelain tiles. The project has a tight schedule, and the screed must be extremely stable to prevent lippage and cracking under high foot traffic.

The Adheseal Solution

Ardex A 38 gives you the control needed for a job of this scale. By mixing the cement with ARDEX Gravel Mix on site, you can produce large, consistent batches. Its exceptional dimensional stability is critical for large format tiles, ensuring the screed surface remains flat. Being ready for tiles in 8 hours means the tiling crew can follow on almost immediately, keeping the project on track.

Best Practice Note

For a bonded screed, ensure the concrete substrate is mechanically prepared and apply a bonding slurry made from Ardex A 38, ARDEX Gravel Mix, and ARDEX P 51. This creates a powerful, monolithic bond essential for commercial-grade durability.

For Waterproofers: High-Volume Wet Area Screeding

The Waterproofer's Challenge

Multiple bathrooms in a hotel development need screeds laid to falls quickly and reliably. The screeds must be ready for subsequent waterproofing application without long delays, to maintain the construction schedule.

The Adheseal Solution

An Ardex A 38 screed is the perfect substrate for waterproofing membranes. Because it cures rapidly through chemical reaction rather than just water evaporation, it has a low retained moisture content. This allows you to apply ARDEX waterproofing systems over the top after just 24 hours, ensuring a fully compatible and secure wet area base that won't compromise the membrane's integrity.