Vison SLU Self-Leveling



Manufacturer: Vison Tech Products LLC


Product Description

VISON SLU SELF-LEVELING is a professional self-leveling underlayment formula. Specialized pourable and auto-leveling are ideal for surface restoration, filling depressed or uneven substrates. Use VISON SLU SELF-LEVELING to fill or raise the old floor surface to a flat and smooth surface prior to installing ceramic tile, natural stone, resilient flooring, carpet, wood, and other floor coverings. VISON SLU SELF-LEVELING is pour applied in spot areas or in the entire room to an application thickness of 0” to ¾” (0-20mm). The flowable characteristic automatically smoothes and flattens trowel marks from 0-10 minutes during installation placement. Use VISON SLU SELF-LEVELING to re-smooth scarred, sloped, uneven, or depressed substrates back to level. Upon placement of the underlayment patch, it will rapidly cure to allow light traffic on the surface within 4-6 hours. VISON SLU SELF-LEVELING is also ideal for interior use beneath the carpet, vinyl, hardwood flooring, ceramic tile, and natural stone installations.




TEXTURE: Powder consisting of Portland cement, polymer additives, graded silica sand, organic and inorganic chemicals

PACKAGING: VISON SLU SELF-LEVELING - 50 lbs. Multi-wall bags; VISON SLU PRIMER - 1-gallon jugs


Basic Use

VISON SLU SELF-LEVELING is used for floor surface correction, surface filling of uneven, tilted, or wavy substrates.


Key Benefits and Features

Fast leveling of floor surfaces, reduce labor with a truer, flatter, level surface for all types of floor finishes.  Floor areas can be corrected with minimal downtime and fast cure time due to the pourable, self-leveling properties.



This product is not recommended for use over floors' surfaces prone to flexing, vibration, or movement. Do not apply over gypsum-based surfaces, hardwood, particle board, parquet, strip wood floors, OSB board, lauan plywood, cushion or sponge-back vinyl flooring, metal, fiberglass, plastic or rubber. Not to be applied over painted, over-spray, old adhesives, curing compounds waxes, oils, sealers, or over unclean, loose, or crumbling surfaces. Not recommended as a wear surface. Not recommended for exterior areas or interior areas prone to moisture or water-soaked. For product installations, the temperature of the area to be leveled must remain above 50°F (10°C) for 72 hours.


Applicable Standards

Tile Council of North America (TCNA) TCNA Handbook for Ceramic Tile Installation, TCNA Method EJ171, ASTM F1869 Standard Test Method for Measuring Moisture Vapor Emission, American National Standards Institute (ANSI) ANSI A108.01 & A108.02.


Installation: Priming

Use of VISON SLU SELF-LEVELING primer is required for proper bond and flow characteristics. All surfaces will have to be brushed or rolled with VISON SLU SELF-LEVELING primer before application. The VISON SLU SELF-LEVELING Primer is diluted 1:1 (primer: clean water) for application.



For best results, maintain all materials, substrates, room, and adhesives at 50°-70°F (10-21°C) for 24 hours before and 72 hours after installation. In a clean container, add 50 lbs. (22.68 kg) VISON SLU SELF-LEVELING to accurately measured 5 quarts (4.7 L) of clean, cool water. Blend VISON SLU SELF-LEVELING powder and water with a ½” heavy-duty drill mixer with an open-loop mixer/paddle at 300-500 rpm for 3 minutes. Do not over water or approximate water levels in mixing, excess water addition causes bond loss, cracking, uneven surface color change, and will void the product warranty. Mix material to a lump-free, uniform, and pourable mix.


General Surface Prep

All surfaces must be dry, and structurally sound. Remove all grease, oil, dirt, curing compounds, sealers, adhesives, or any other contaminant that would prevent a good bond. Glossy or painted surfaces must be sanded, and stripped of all contaminants. Concrete must be free of efflorescence and not subject to hydrostatic pressure. Concrete slabs should have a coarse finish to enhance the bond. Plywood flooring including those under resilient flooring must be structurally sound and meet all ANSI and deflection requirements. Ambient temperature should be maintained above 50° F (10° C) or below 100° F (38° C) for 72 hours to achieve a proper bond. All surfaces will require VISON SLU SELF-LEVELING Primer to substrate and between additional applications pours. VISON SLU SELF-LEVELING Primer covers approximately 150-200 sq. ft (14-18 m2)


Cementitious Substrates

Concrete must be fully cured and must accept water penetration. Contaminants should be mechanically removed before installation. Brush or roll surface with properly diluted VISON SLU SELF-LEVELING Primer. After brushing the primer to the surface, allow the primer coat to dry clear to touch. If primer dries longer than 12 hours before underlayment placement it will be necessary to re-prime the surface.


EGP Plywood Substrates

All EGP Plywood floors shall be rigid and non-flexing for live and dead loads. Floor structure and construction shall conform to surfaces TCNA handbook F150 and ANSI A108.01 Part 3.4, interior application, properly gapped, glued, and screwed. Brush or roll surface with properly diluted VISON SLU SELF-LEVELING Primer. After brushing the primer to the surface, allow the primer coat to dry clear to touch before applying the patch. Use corrosion-resistant staples and attach ¼” (6mm) galvanized, expanded metal lath or corrosion-resistant plastic lath to the EGP Plywood before applying VISON SLU SELF-LEVELING. For questions about proper subfloor installation, call VISON Technical department.


Tile over Tile and Other Surfaces

The surface must be Portland cement bond compatible, the old surface must be well bonded and without waxes, sealer, or coatings. Smooth or slick surfaces will be heavily scratched, scarred, coarse sanded, or abraded to provide a mechanical bond. Brush or roll surface with properly diluted VISON SLU SELF-LEVELING Primer. After brushing the primer to the surface, allow the primer coat to dry clear to touch before applying the patch.


Expansion Joints

Install expansion joints around all perimeters or restraining surfaces where possible to allow for expansion movement. Expansion joints and cold joints, as described in ANSI A108.01, should never be bridged with setting material. They must be brought through the tile work and filled with an appropriate elastomeric sealant (100% Silicone).  Contact Vison Tech’s Technical Services for the proper treatment of control or saw-cut joints. Refer to TCNA Handbook EJ171 , F125 and  F125A.



After brushing primer to the surface, allow primer coat to dry clear to touch before applying Vison SLU Self Leveling. Pour the self-leveling underlayment patch in the lowest areas first and work outward adding additional product to the pre-primed surface. Foam insulation tape can be used to dam or block underlayment mixture from flowing to unwanted areas.  Application pours greater than ¾” layer can be modified with additional dry, clean 0”-3/8” gravel volume of 3 quarts of aggregate per bag. The additional gravel mix will allow pours up 2” (50mm)


Trowel Recommendation

Smaller tiles will use smaller notched trowels and larger tiles will require larger notched trowels suitable for providing a minimum 3/32" - 3/4" (3 – 20 mm) bed thickness after embedding the tile. Spot bonding or mortar dollops application does not meet installation trade practices and provides proper adhesion and impact support.



Per 50 lbs. (22.7 kg) bag using a square-notched trowel covers:
at 1/8” layer = 50 sq. ft. (4.6 m2);
at 1/4” layer = 25 sq. ft. (2.3 m2);

at 1/2" layer = 12.5 sq. ft. (1.1 m2)


Working Time

Approximately 0-30 minutes, depending on ambient temperature.



Clean tools, hands, and excess materials from the face of the tile, while the mortar is still fresh, with warm soapy water.


Curing and Grouting

Ceramic tile and stone may be installed or set when the underlayment is firmly in place, typically 16 to 24 hours after installation is completed. Carpet, resilient flooring, and wood floors products will be checked by moisture meter and are to be within levels stated by those floor covering manufacturer’s recommendations. Cold temperatures or high humidity may extend curing time.