Understanding Gypsum Based Self Leveling Mortar: Material Grades, Performance, and Industrial Uses

Types of Gypsum-Based Self-Leveling Mortars

A gypsum-based self-leveling mortar is a specialized flooring underlayment designed to create a smooth, flat, and durable surface prior to the installation of finished floor coverings. These mortars are widely used in residential, commercial, and industrial construction due to their excellent flowability, dimensional stability, and compatibility with various substrates.

Choosing the right type of self-leveling gypsum mortar is essential for ensuring long-term performance, structural integrity, and compatibility with final floor materials such as tile, vinyl, laminate, or carpet. Selection is typically based on three key criteria: compressive strength, setting time, and flexibility or compatibility with coverings and environmental conditions.

Standard Strength Gypsum Mortars

Ideal for general-purpose flooring applications where moderate loads and normal foot traffic are expected.

Advantages

• Excellent flow and self-leveling properties
• Suitable for most interior flooring projects
• Provides a stable base for common floor coverings
• Longer working time allows for larger area pours

Limitations

• Not recommended for high-traffic or heavy-load areas
• Slower drying time compared to rapid-setting types
• Limited use in commercial or industrial settings

Best for: Residential interiors, apartments, offices, and light commercial spaces

High Strength Gypsum Mortars

Engineered for environments requiring superior load-bearing capacity and long-term durability.

Advantages

• Higher compressive strength (typically 20–30 MPa)
• Resistant to cracking under heavy loads
• Fast setting and early strength development
• Ideal for commercial and industrial applications

Limitations

• Higher material cost
• Requires precise mixing and application
• May need primer or bonding agent for adhesion

Best for: Retail spaces, warehouses, schools, and high-traffic corridors

Rapid Hardening Gypsum Mortars

Formulated for fast-track construction and time-sensitive projects where quick return-to-service is critical.

Advantages

• Can be walked on in as little as 2–4 hours
• Enables same-day or next-day floor covering installation
• Minimizes project downtime
• Excellent for emergency repairs and renovations

Limitations

• Short working time (pot life of 20–30 minutes)
• Demanding application process requiring skilled labor
• More sensitive to mixing ratios and ambient conditions

Best for: Renovations, hotels, hospitals, and fast-turnaround construction

Flexible Gypsum Mortars

Designed to accommodate dynamic structural movement and thermal expansion/contraction.

Advantages

• High elasticity reduces risk of cracking
• Performs well in areas with temperature or humidity fluctuations
• Compatible with underfloor heating systems
• Protects sensitive floor finishes like ceramic or stone

Limitations

• Higher cost due to polymer additives
• Slightly longer drying time than standard mortars
• May require special primers or vapor barriers

Best for: Bathrooms, kitchens, conservatories, and buildings with radiant heating

Gypsum Mortars with Added Aggregates

Enhanced formulations incorporating sand, quartz, or lightweight aggregates to improve performance characteristics.

Advantages

• Improved thermal insulation properties
• Better sound absorption and acoustic damping
• Increased thickness capability without cracking
• Greater dimensional stability in thick applications

Limitations

• Heavier than standard formulations
• Requires more material and labor for mixing
• May need mechanical pumping for large pours

Best for: multi-story buildings, sound-sensitive areas, and thick leveling applications

Type	Compressive Strength	Setting Time	Flexibility	Best Application
Standard Strength	10–15 MPa	4–6 hours	Low	Residential, light commercial
High Strength	20–30 MPa	2–4 hours	Low	Industrial, retail, high-traffic areas
Rapid Hardening	15–25 MPa	1–3 hours	Medium	Renovations, fast-track projects
Flexible	12–18 MPa	3–5 hours	High	Underfloor heating, moisture-prone areas
With Aggregates	10–20 MPa	4–6 hours	Medium	Thick pours, acoustic insulation

Expert Tip: Always check compatibility with underfloor heating systems and final floor coverings before selecting a mortar. Use a moisture meter to ensure the slab is sufficiently dry before installing sensitive finishes like wood or vinyl.

Important Features of Gypsum-Based Self-Leveling Mortars

Gypsum-based self-leveling mortars are widely used in modern construction due to their excellent flowability, dimensional stability, and compatibility with various flooring systems. Selecting the right product involves evaluating several performance-critical features that influence ease of application, long-term durability, and overall floor system integrity.

Workability

Workability is a primary factor in determining how efficiently a self-leveling mortar can be mixed, poured, and finished. High workability allows for effortless spreading using a gauge rake or squeegee, ensuring uniform coverage even over large or complex surfaces.

Modern gypsum-based formulations often include advanced rheology modifiers and water-reducing agents to enhance flow without compromising strength. These additives improve pumpability and reduce labor time, making them ideal for both manual and mechanized applications.

Additionally, many self-leveling mortars offer extended open times—typically between 20 to 40 minutes—giving contractors ample opportunity to correct imperfections before initial set begins. This flexibility is especially valuable on large-scale commercial projects where continuous pouring is required.

Setting Time

The setting time of a gypsum-based self-leveling mortar refers to the period from mixing until the material begins to gain structural rigidity. This can vary significantly based on formulation, ambient temperature, humidity, and substrate conditions.

Standard products typically set within 1–2 hours, while rapid-setting variants can harden in as little as 30 minutes. These fast-setting options are ideal for renovation projects or areas requiring quick turnaround, such as retail spaces or rental properties.

However, reduced working time requires precise planning and efficient application techniques. Conversely, extended-setting mortars are beneficial in hot climates or large pours where a longer processing window helps prevent cold joints and ensures consistent finishing.

Surface Finish

Achieving a smooth, defect-free surface is one of the main purposes of self-leveling mortars. A high-quality finish minimizes undulations and surface irregularities, providing an optimal substrate for final floor coverings like vinyl, laminate, ceramic tile, or polished finishes.

Advanced gypsum formulations are engineered to self-bleed and self-compact, reducing pinholes and surface bubbles. Some premium mortars achieve a near-glass-like flatness (tolerances within ±2 mm over 3 meters), significantly reducing or eliminating the need for grinding or skim coating.

This not only saves time and labor but also enhances the aesthetic quality of the final floor, particularly in high-end residential and commercial installations.

Thermal and Acoustic Insulation

Beyond leveling, many gypsum-based mortars contribute to improved thermal and acoustic performance. This is especially critical in multi-residential buildings, hotels, and mixed-use developments where sound transmission and energy efficiency are key concerns.

Insulating properties are enhanced by incorporating lightweight aggregates such as expanded perlite, vermiculite, or polystyrene beads. These materials reduce density while increasing air void content, which acts as a barrier to heat transfer and sound waves.

Some systems achieve sound reduction ratings (ΔLw) of up to 20 dB and thermal resistance (R-values) suitable for underfloor heating applications, making them a functional component of sustainable building designs.

Compatibility with Floor Coverings

Ensuring compatibility between the self-leveling mortar and the final floor covering is essential to prevent delamination, staining, or chemical incompatibility. Gypsum-based mortars must be fully cured and, in some cases, primed or sealed before installing sensitive materials like LVT, engineered wood, or carpet.

Many modern mortars are formulated with bonding agents or come with recommended primer systems that enhance adhesion to both the substrate and subsequent layers. They are also designed to be pH-neutral upon curing, preventing damage to adhesives or floor membranes.

Always consult manufacturer guidelines to confirm compatibility with specific floor types, especially when using moisture-sensitive materials or installing over underfloor heating systems.

Durability

Durability ensures that the self-leveling layer maintains its integrity under long-term mechanical stress, foot traffic, and environmental exposure. Gypsum-based mortars are typically reinforced with synthetic fibers or fine aggregates to improve tensile strength and crack resistance.

High-compressive-strength variants (up to 25 MPa) are suitable for commercial and industrial environments, including warehouses, retail stores, and public buildings. These formulations resist abrasion, point loading, and impact, minimizing chipping and surface degradation.

When properly applied and protected, gypsum self-leveling mortars can last the lifetime of the building, provided moisture exposure is controlled and floor coverings are maintained.

Feature	Importance	Performance Tips
Workability	High	Choose mortars with flow >180 mm (ASTM C920); use additives for pumpability in large pours
Setting Time	High	Use rapid-set for repairs; standard-set for large areas. Monitor temperature and humidity
Surface Finish	High	Select fine-grade mortars for seamless flooring; aim for flatness ≤2 mm/3 m
Thermal & Acoustic Insulation	Medium to High	Opt for lightweight formulations with perlite or EPS for sound control and energy efficiency
Compatibility	High	Always use manufacturer-recommended primers and check curing status before installation
Durability	High	Use fiber-reinforced mortars in high-traffic zones; avoid moisture exposure post-installation

Important: Always follow the manufacturer’s technical data sheet for mixing ratios, application conditions, and curing requirements. Improper installation—such as applying over damp substrates or skipping priming steps—can lead to cracking, delamination, or flooring failure. Proper surface preparation and environmental control are just as critical as material selection.

Commercial Applications of Gypsum-Based Self-Leveling Mortars

Gypsum-based self-leveling mortars have become a cornerstone in modern construction due to their versatility, speed of application, and excellent performance characteristics. These advanced flooring solutions are engineered to provide a smooth, flat, and durable substrate across a wide range of environments—from homes to high-traffic commercial spaces. Their unique properties make them ideal for both new builds and renovation projects where precision, efficiency, and long-term durability are paramount.

Residential Flooring

Gypsum-based self-leveling mortars are widely used in residential construction and remodeling to create perfectly flat subfloors before installing final floor coverings such as ceramic tile, natural stone, hardwood, laminate, or carpet.

• Provides a seamless base that prevents lippage and uneven wear in finished flooring
• Reduces noise transmission between floors, enhancing acoustic comfort
• Ideal for underfloor heating systems due to excellent thermal conductivity and crack resistance
• Fast drying (typically 24–48 hours) allows quicker project completion, minimizing disruption during renovations

Key benefit: Enables DIY and professional installers to achieve professional-grade results with minimal effort and time investment.

Office Spaces and Commercial Buildings

In office environments and high-rise commercial buildings, floor flatness is critical not only for aesthetics but also for structural integrity and tenant satisfaction.

• Supports raised access flooring systems commonly used in data centers and modern offices
• Offers high compressive strength (typically 15–25 MPa), capable of withstanding heavy furniture, equipment, and consistent foot traffic
• Enables rapid installation cycles, reducing downtime during tenant fit-outs or retrofits
• Compatible with moisture-resistant primers for use over concrete slabs with residual dampness

Pro tip: Use laser-guided screeding tools with self-leveling mortars to ensure precise floor flatness (FF/FL standards) required in corporate environments.

Educational and Institutional Facilities

Schools, universities, libraries, and government buildings benefit significantly from the durability and low-maintenance nature of gypsum-based self-leveling mortars.

• Withstands constant student and staff movement, including carts, chairs, and mobile learning equipment
• Minimizes tripping hazards by eliminating uneven transitions between rooms or floor sections
• Cost-effective over the lifecycle due to reduced repair frequency and long service life
• Can be applied during summer breaks or holiday periods thanks to fast curing times

Critical advantage: Contributes to ADA compliance by ensuring accessible, slip-resistant, and uniformly level surfaces.

Healthcare Facilities

Hospitals, clinics, and long-term care centers demand flooring systems that support hygiene, safety, and operational continuity—gypsum mortars meet these needs effectively.

• Creates a seamless, non-porous surface that resists mold, bacteria, and contamination when properly sealed
• Naturally fire-resistant (gypsum releases water vapor when exposed to heat, slowing flame spread)
• Environmentally friendly with low VOC emissions, contributing to better indoor air quality
• Smooth finish improves maneuverability for wheelchairs, stretchers, and medical carts

Safety note: Ideal for sensitive environments where patient well-being and infection control are top priorities.

Retail and Hospitality

In retail stores, shopping malls, restaurants, hotels, and resorts, first impressions matter—flooring plays a key role in customer experience and brand perception.

• Delivers a flawless base for high-end finishes like polished concrete, vinyl planks, or decorative tiles
• Enhances visual appeal by eliminating shadows and distortions caused by uneven substrates
• Quick installation allows for overnight floor prep in busy locations, minimizing business interruption
• Supports radiant heating in lobbies, spas, and guest bathrooms for added comfort

Design insight: A perfectly level floor amplifies lighting effects and spatial perception, elevating the overall ambiance.

Industrial Settings

Warehouses, manufacturing plants, workshops, and distribution centers require robust flooring solutions that can endure heavy machinery, forklifts, and chemical exposure.

• Provides a smooth, abrasion-resistant surface that facilitates efficient movement of pallet jacks and automated guided vehicles (AGVs)
• High load-bearing capacity supports static and dynamic industrial loads
• Can be enhanced with additives for improved chemical resistance and impact strength
• Reduces maintenance costs by minimizing cracks and spalling common in poorly prepared substrates

Operational benefit: Improves workplace safety and logistics efficiency in large-scale industrial operations.

Professional Recommendation: When specifying gypsum-based self-leveling mortars, always consider environmental conditions such as humidity, temperature, and substrate moisture content. Use manufacturer-recommended primers and edge barriers to ensure adhesion and prevent shrinkage cracks. For critical applications, opt for fiber-reinforced or polymer-modified formulations to enhance tensile strength and crack resistance.

Application Sector	Key Performance Needs	Recommended Mortar Features	Typical Curing Time
Residential	Fast drying, compatibility with underfloor heating	Low shrinkage, pumpable consistency	24–48 hours
Commercial Offices	High flatness (FF/FL), durability	Fiber-reinforced, high compressive strength	24–72 hours
Educational Facilities	Impact resistance, low maintenance	Durable top layer, abrasion-resistant	48 hours
Healthcare	Hygiene, fire safety, accessibility	Non-toxic, fire-rated, seamless finish	36–48 hours
Retail & Hospitality	Aesthetic quality, rapid turnaround	Polishable, color-stable, quick-set	24–48 hours
Industrial	Load-bearing, chemical resistance	Heavy-duty, polymer-modified	72+ hours (with full cure)

Additional Considerations

• Moisture Management: Use vapor retarders or moisture-tolerant formulations when installing over concrete with high relative humidity
• Sustainability: Gypsum is recyclable and often made from industrial byproducts (e.g., flue gas desulfurization), supporting green building certifications like LEED
• Sound Dampening: Many gypsum mortars offer inherent sound insulation properties, beneficial in multi-story buildings
• Crack Suppression: Combined with crack isolation membranes, they help prevent reflective cracking in tile installations
• Application Thickness: Can be applied from 5 mm to 50+ mm depending on product type, allowing correction of significant floor irregularities

How to Choose Gypsum-Based Self-Leveling Mortars: A Comprehensive Guide

Selecting the right gypsum-based self-leveling mortar is essential for achieving a durable, smooth, and functional flooring substrate. These advanced materials offer numerous advantages over traditional concrete, including faster installation, improved dimensional stability, and enhanced sustainability. However, making the correct choice depends on a thorough understanding of your project’s specific requirements. This guide explores the key factors to consider when selecting a gypsum-based self-leveling mortar to ensure optimal performance, cost-efficiency, and long-term durability.

Important Note: Always verify compatibility with underfloor heating systems, moisture conditions, and final floor coverings. Using an incompatible product can lead to delamination, cracking, or flooring failure.

Compressive Strength

The compressive strength of a self-leveling mortar determines its ability to withstand loads without cracking or deforming. This property should align directly with the intended use of the space.

• High-strength mortars (25–40 MPa): Ideal for industrial facilities, warehouses, commercial kitchens, and areas with heavy foot traffic or rolling loads (e.g., shopping malls, showrooms).
• Standard-strength mortars (15–25 MPa): Suitable for residential interiors, offices, and light commercial spaces where load demands are moderate.
• Low-strength options: May be used as acoustic or thermal underlayments in non-traffic areas, often combined with a wear layer.

Always consult structural requirements and flooring manufacturer recommendations before finalizing your selection.

Setting Time

Setting time significantly impacts project scheduling and workflow efficiency. Different formulations offer varying working windows and cure speeds.

• Rapid-setting mortars: Set in as little as 1–2 hours, allowing foot traffic within 4–6 hours. Perfect for urgent repairs, fast-track renovations, or projects with tight deadlines.
• Normal-setting mortars: Provide a working time of 20–40 minutes and require 12–24 hours before walking on the surface. Suitable for most standard installations.
• Extended-workability mortars: Offer up to 60 minutes of flow time, ideal for large-scale pours or complex layouts where consistent application is critical.

Consider ambient temperature and humidity, as these can affect setting behavior. Some products include additives to control set time under varying site conditions.

Surface Finish and Compatibility with Floor Coverings

The final surface texture of the mortar influences both aesthetics and adhesion for subsequent flooring layers.

• Smooth-finish mortars: Deliver a polished, flat surface that minimizes the need for sanding or priming. Excellent for vinyl, carpet, laminate, and LVT installations.
• Textured or aggregate-modified mortars: Provide enhanced mechanical bond for tile, stone, or epoxy coatings. These often contain fine quartz or silica sand to improve grip.
• Self-priming formulations: Reduce labor by eliminating the need for a separate primer coat, speeding up installation.

Ensure the mortar's surface profile matches the flooring manufacturer’s specifications to prevent adhesion failure.

Thermal and Acoustic Properties

Modern gypsum-based mortars are engineered to contribute to building energy efficiency and occupant comfort.

• Thermal insulation: Some mortars incorporate lightweight aggregates (e.g., perlite, polystyrene beads) to reduce thermal conductivity, making them ideal for use with underfloor heating systems.
• Sound damping: Acoustic-grade mortars include elastomeric additives or foam cells that absorb impact noise (IIC ratings), crucial for multi-story residential and commercial buildings.
• Fire resistance: Gypsum naturally releases water vapor when exposed to fire, contributing to passive fire protection in floor assemblies.

These enhanced properties make specialized mortars a smart choice for green buildings, apartments, hotels, and healthcare facilities.

Cost Considerations

While initial cost is a factor, it’s essential to evaluate total project value, including labor, speed of installation, and long-term performance.

• Standard mortars: Offer the lowest upfront cost and are cost-effective for basic leveling in low-traffic areas.
• Premium formulations: Such as rapid-set, high-strength, or acoustic variants, may cost 20–50% more but deliver time savings, reduced labor, and improved building performance.
• Long-term savings: Faster return-to-service, lower energy costs (via thermal mass), and reduced maintenance can offset higher initial material costs.

Always conduct a lifecycle cost analysis for large or high-value projects.

Environmental Impact and Sustainability

Gypsum-based mortars are among the most sustainable flooring solutions available today.

• Low carbon footprint: Gypsum requires significantly less energy to process than Portland cement, reducing CO₂ emissions by up to 70%.
• Recycled content: Many products use recycled gypsum from construction waste or industrial byproducts (e.g., flue-gas desulfurization gypsum).
• Indoor air quality: Low-VOC or zero-VOC formulations contribute to healthier indoor environments and help achieve LEED, BREEAM, or WELL certification.
• Recyclability: At end-of-life, gypsum can be crushed and reused in new products, supporting circular economy principles.

Ease of Application and Installation Method

The application method affects labor requirements, consistency, and overall project timeline.

• Manual application: Best for small areas (<50 m²). Requires mixing by hand or drill mixer and spreading with a gauge rake and trowel. More labor-intensive but flexible for tight spaces.
• Mechanical pumping: Ideal for large areas (>100 m²). Uses specialized pumps to deliver a consistent flow, reducing labor time by up to 60% and minimizing human error.
• Flowability: High-flow mortars (spread up to 10 mm without screeding) ensure excellent self-leveling and reduce the need for skilled labor.

Ensure your team is trained and equipped for the chosen method. Some manufacturers offer on-site support or certified applicator programs.

Selection Factor	Ideal Use Case	Product Examples	Key Benefits
High Compressive Strength	Warehouses, industrial floors	40 MPa rapid-hardening mortar	Durability under heavy loads, crack resistance
Rapid Setting	Renovations, tight deadlines	2-hour walk-on mortar	Faster project completion, reduced downtime
Acoustic Performance	Apartments, hotels, offices	Sound-dampening underlayment	Improved IIC ratings, occupant comfort
Thermal Insulation	Floors with underfloor heating	Lightweight insulating mortar	Energy efficiency, even heat distribution
Sustainability Focus	Green building projects	High-recycled-content mortar	LEED points, low emissions, healthy interiors

Expert Tip: Always perform a small test pour before full-scale application. This allows you to evaluate flow, setting time, surface finish, and adhesion under actual site conditions, minimizing the risk of costly rework.

Additional Selection Tips

• Check manufacturer warranties and technical support availability.
• Verify moisture tolerance—some mortars are designed for damp substrates, while others require a dry base.
• Ensure compatibility with vapor barriers and bonding agents.
• Store materials in a dry, temperature-controlled environment to maintain performance.
• Follow mixing instructions precisely—adding too much water can weaken the final product.

Choosing the right gypsum-based self-leveling mortar involves balancing technical performance, environmental goals, and budget constraints. By carefully evaluating compressive strength, setting time, finish requirements, thermal-acoustic needs, cost, sustainability, and ease of application, you can select a product that not only meets but exceeds your project expectations. When in doubt, consult with technical representatives from reputable manufacturers to ensure the best possible outcome.

Frequently Asked Questions About Self-Leveling Compounds

Q1: Can self-leveling compound be used over concrete?

Yes, self-leveling compound is commonly and effectively applied over existing concrete surfaces. It serves as an excellent solution for preparing subfloors before installing new flooring materials such as tile, vinyl, laminate, or hardwood.

• Surface Preparation: The concrete must be clean, structurally sound, and free of oil, dust, or loose particles. A primer is often required to ensure proper adhesion.
• Crack Repair: Minor cracks and surface imperfections can be filled and smoothed over with the compound, though large structural issues should be repaired beforehand.
• Thickness: Most self-leveling compounds can be applied from 1/8 inch up to 1 inch thick, depending on the product specifications.
• Benefits: Provides a seamless, ultra-flat surface that enhances the durability and appearance of the final floor covering.

Always follow manufacturer guidelines for mixing, application, and drying times to achieve optimal results.

Q2: What is the difference between concrete and gypsum floor leveling compounds?

While both concrete and gypsum-based leveling compounds are used to create even subfloors, they differ significantly in composition, performance, and application:

Feature	Concrete-Based Leveler	Gypsum-Based Leveler
Material Composition	Cementitious (cement, sand, polymers)	Calcium sulfate (gypsum), additives
Strength & Durability	High compressive strength; ideal for heavy foot traffic and commercial use	Lower strength; best suited for residential or light-duty applications
Weight	Heavier—may require structural evaluation in upper floors	Lighter—reduces load on structures, ideal for renovations
Drying Time	Slower drying (24–72 hours); longer curing period	Faster drying (6–24 hours); allows quicker follow-up work
Movement Tolerance	Less flexible; prone to cracking under substrate movement	More dimensionally stable; handles minor shifts better
Indoor Air Quality	Can release more moisture during curing	Lower moisture emission; often preferred under moisture-sensitive flooring

In summary, choose concrete-based levelers for high-traffic or industrial areas, and gypsum-based products for faster installations and lighter-weight requirements in residential settings.

Q3: Where is self-leveling compound typically used?

Self-leveling compound is a versatile flooring solution used across various residential, commercial, and industrial environments to correct uneven surfaces and prepare for final flooring installation. Common applications include:

• Residential Renovations: Leveling old concrete slabs before laying luxury vinyl plank (LVP), engineered wood, or ceramic tile.
• Commercial Buildings: Creating smooth, professional-grade floors in offices, retail stores, and medical facilities.
• Industrial Facilities: Preparing durable, flat surfaces in warehouses or factories where heavy machinery or forklifts operate.
• Underfloor Heating Systems: Encasing radiant heating pipes in a uniform layer that ensures even heat distribution.
• Multi-Level Floors: Bridging height differences between rooms or transitions between different floor types.
• Sound Dampening: Some compounds are formulated with acoustic properties to reduce impact noise in multi-story buildings.

Its rapid setting time (often walkable within 2–4 hours) and ability to flow into hard-to-reach areas make it a preferred choice for efficient, high-quality floor preparation.

Q4: Is gypsum self-leveling compound waterproof?

No, standard gypsum-based self-leveling compounds are not waterproof. They are inherently water-soluble and can degrade when exposed to prolonged moisture or high humidity. However, there are ways to improve their resistance:

• Surface Sealants: Applying a waterproof membrane, wax coating, or acrylic sealer can make the surface water-resistant and protect against spills or damp conditions.
• Moisture Barriers: Installing a vapor retarder beneath the compound can prevent rising damp from the subfloor.
• Indoor Use Only: Gypsum levelers are best suited for dry, interior environments such as living rooms, bedrooms, or offices.
• Avoid Wet Areas: Do not use in bathrooms, kitchens, laundry rooms, basements prone to flooding, or outdoor spaces unless specifically formulated for such conditions.
• Specialty Products: Some manufacturers offer modified gypsum or cement-based alternatives designed for higher moisture tolerance—always check product data sheets.

For wet or high-humidity environments, consider using a cementitious self-leveling compound with waterproofing additives or a dedicated moisture-resistant underlayment system to ensure long-term performance and floor integrity.