Installs from featheredge to any thickness.  Fast-track system  Install floor covering just 16 hours, walkable in just 2-3 hours.  No troweling required.  Not a gypsum product
Portland cement-based, high strength, fast-setting, non-shrink underlayment.  Mix with water, pour or pump, spread, ready! Product Capabilities: For use over concrete, metal, terrazzo, ceramic tile, wood and old flooring adhesive residue (including cutback), on above or below grade.  Pourable or pumpable. Installs from featheredge to 1 1/2" in one operation; up to 5" with the addition of proper aggregate. Designed specifically for fast leveling of floors, ARDEX K-15 provides a durable, flat and smooth floor surface with minimum labor and installation time. ARDEX K-15 hardens quickly by hydration and drying. It will not shrink, crack or spall, even when applied in thick layers. Floor coverings can be installed just 16 hours later. ARDEX K-15 is recommended and specified by most flooring manufacturers, architects, and contractors. 4100 psi.

Technical Information

DESCRIPTION
Designed  specifically  for  fast  leveling  of  floors, ARDEX K-15 provides a durable, flat and smooth floor surface with minimum labor and installation time. ARDEX K-15 is recommended or specified by many quality flooring manufacturers, architects and contractors.

RANGE OF APPLICATION
ARDEX K-15 will level and smooth concrete and other subfloors prior to the installation of resilient flooring, ceramic tile,  carpeting,  wood  parquet,  athletic  floors, etc.  ARDEX K-15 can be used for a wide variety of indoor applications above, on or below grade, including:

Level Over: Concrete Ceramic Wood Cutback adhesive residue and more!

New Construction Unlevel concrete  Rough concrete  Rained-on concrete  Frozen concrete  Unfinished concrete  Rough-screeded concrete  Camber problems  Rehabilitation Projects Terrazzo  Quarry and ceramic tile  Old Concrete  Smoothing floors over cutback and non-water soluble adhesive residues on concrete  Wooden floors  Steel decking

Technical Data:

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Technical Information • Installation Instructions • MSDS

Installation Instructions

Note: This product is intended to be installed at an average depth of not less than 1/8" over the highest point on the floor and can be featheredged to match elevations. This product is designed for interior use over dry substrates only. Do not use in areas of constant water exposure nor in areas exposed to permanent or intermittent substrate moisture as this may jeopardize the performance of the underlayment and floor covering system. This product is not a vapor barrier and will allow free passage of moisture. Follow the directives of the flooring manufacturer regarding maximum allowable moisture content and test the substrate prior to installing ARDEX K-15.

SUBFLOOR PREPARATION
Gypsum, latex patches, asphalt, coal tar, and lightweight insulating concrete are not suitable substrates for the installation of ARDEX K-15. 
Concrete floors:  Must be solid, thoroughly clean, free of oil, wax, grease, latex or gypsum patching compounds, curing and sealing compounds, or any contaminant which may act as a bond breaker before priming with ARDEX P-51 Primer.  Overwatered, frozen or otherwise weak or contaminated concrete surfaces must be mechanically cleaned to a sound solid surface by shotblasting, scarifying or similar.  Acid etching and the use of solvents are not acceptable means of cleaning the substrate.
Non-porous floors, such as terrazzo, ceramic and quarry tile, certain power-troweled (burnished) concrete, and epoxy coatings: must be solid, well bonded, properly cleaned, and primed with ARDEX P-82 Ultra Prime.  Steel decking should be rigid and treated with an anti-corrosive paint before priming with ARDEX P-82.
Wooden subfloors and concrete contaminated with cutback adhesive:   refer to the instructions for the installation of ARDEX K-15 over these substrates located under separate headings in this brochure.
Note:  All subfloors must be dry and properly primed for a successful installation.  Substrate temperature must be a minimum of 50ºF for installation of ARDEX products.  For further information, please refer to the ARDEX Substrate Preparation brochure. Always install an adequate number of properly located test areas, which include the finish flooring, to ensure the suitability of the system for its intended use. As floor coverings vary, contact and rely upon the floor covering manufacturer for specific directives, to include requirements such as maximum allowable moisture content, adhesive selection, and intended end use of the product.

RECOMMENDED TOOLS:ARDEX T-1 Mixing Paddle, ARDEX T-10 Mixing Drum, ARDEX T-4 Spreader, ARDEX T-5 Smoother, ARDEX M-7 Measuring Bucket (7 quarts), 1/2" heavy-duty drill (min. 650 rpm).

PRIMING
Standard absorbent concrete:   Prime  with  ARDEX P-51 Primer diluted 1:1 with water. Apply evenly with a soft, nylon pushbroom with exploded tips. Do not use paint rollers, mops, or spray equipment.  Do not leave any bare spots.  Brush off puddles and excess primer.  Allow to dry to a clear, thin film for a minimum of  3 hours, maximum of  24 hours.

Extremely absorbent concrete may require two applications of ARDEX P-51 to avoid the formation of bubbles and pinholes in the ARDEX K-15.  In such cases, make an initial application of ARDEX P-51 diluted with 3 parts water.  Let dry thoroughly (1 to 3 hours) and install a second application of ARDEX P-51 mixed 1:1 with water.
Non-porous subfloors, wood, cutback, and metal:  Prime with ARDEX P-82 Ultra Prime.  Mix Part A (red) with Part B (white) and apply in as thin a layer as possible using  a squeegee or  a short-nap or sponge paint roller, leaving a thin coat of primer no heavier than a thin coat of paint.  Do not leave any bare spots.  Brush off puddles and excess primer.  Allow to dry to a thin, slightly tacky film (min. 3 hours, max. 24 hours).  Cutback and other adhesive residues require that the primer dry for a minimum of 18 hours. Complete priming instructions for wooden substrates and cutback adhesive residues are included under separate headings in this brochure.
Caution:  ARDEX P-82 must be applied in a thin layer within one hour of mixing.  A thick coat will produce a soft and rubbery surface which can result in cracking of the ARDEX K-15 Underlayment.
Note:  Low substrate temperatures and/or high ambient humidity require longer drying time for ARDEX primers.  Do not install ARDEX K-15 before primer has dried thoroughly.

MANUAL INSTALLATION
ARDEX K-15 is mixed in 2-bag batches at one time.  For each bag, add 7 quarts (6.5 liters) of water.  Put the water in the ARDEX T-10 Mixing Drum first, then add each bag of ARDEX K-15 while mixing at full speed with an ARDEX T-1 Mixing Paddle and a 1/2" heavy-duty drill (min. 650 rpm).  Mix thoroughly for 2-3 minutes to obtain a lump-free mix. DO NOT OVERWATER!  A yellowish foam while mixing indicates overwatering.
When installing ARDEX K-15 in high-stress areas or over wood, cutback or metal, the addition of ARDEX E-25 Resilient Emulsion is required to increase the resiliency of the ARDEX K-15 Underlayment.  Mix 2 quarts (2 liters) of ARDEX E-25 with 6 quarts (5.5 liters) of water for each bag of ARDEX K-15 and follow the mixing instructions above.
ARDEX K-15 has a flow time of 10 minutes at 70ºF.  Pour the liquid mix on the floor and spread with the ARDEX T-4 Spreader.  Immediately smooth the material with the ARDEX T-5 Smoother.  Wear baseball or soccer shoes with non-metallic cleats to avoid leaving marks in the liquid ARDEX K-15.

PUMPING INSTALLATION
ARDEX K-15 can also be installed using ARDEX Levelcraft Automatic Mixing Pumps.  The Levelcraft Pumps provide for high productivity and a smoothly running, consistent installation.  The Levelcraft Pumps may be rented from a local authorized ARDEX Distributor and are supported by the ARDEX Technical Service Department.
Start the pump at 210 gallons of water per hour, then adjust to the minimum water reading which still allows self-leveling properties.  DO NOT OVERWATER!  Check the consistency of the product on the floor to ensure a uniform distribution of the sand aggregate at both the top surface and bottom of the pour.  Conditions during the installation such as variations in water, powder, substrate and ambient temperature, require that the water setting be adjusted during installation to avoid overwatering.
When installing ARDEX K-15 in high-stress areas or over wood, cutback, or metal, the addition of ARDEX E-25 Resilient Emulsion is required to increase the resiliency of the ARDEX K-15 Underlayment.  Please contact the ARDEX Technical Service Department for information on pumping ARDEX K-15 + E-25.
ARDEX K-15 has a flow time of 10 minutes at 70ºF.  Pump the liquid mix on the floor and spread with the ARDEX T-4 Spreader.  Immediately smooth the material with the ARDEX T-5 Smoother.  Wear baseball or soccer shoes with non-metallic cleats to avoid leaving marks in the liquid ARDEX K-15.
Please contact the ARDEX Technical Service Department for complete pump installation instructions, to include the Operation and Instruction Guidelines.

THICKNESS OF INSTALLATION
ARDEX K-15 can be installed from a featheredge to 1 1/2" in a single application, and up to 5" with the addition of proper aggregate.  For installations exceeding 5", contact the ARDEX Technical Service Department.  Mix ARDEX K-15 with a washed, dried and well-graded pea gravel, 1/8" - 1/4" or larger. (Nominal aggregate size should not exceed 1/3 the depth of the thickness being poured.)  Mix ARDEX K-15 with water first, then add from 1/3 up to 1 part by volume of aggregate and mix until the aggregate is completely coated. Do not use sand. If the aggregate is wet, reduce the amount of water to avoid overwatering.
The addition of aggregate will diminish the workability of the product and may make it necessary to install a finish layer.  Allow the first layer to dry 12-16 hours.  Prime the surface with ARDEX P-51 mixed 1:1 with water, following priming instructions.  Allow the primer to dry thoroughly (min. 3 hours, max. 24 hours) and install the finish layer.
Note: ARDEX K-15 is a cementitious material.  Observe the basic rules of concrete work.  Do not install below 50ºF surface temperature.  Install quickly if the floor is warm and follow hot weather instructions available from the ARDEX Technical Service Department.  Never mix with cement or additives other than ARDEX-approved products.  DO NOT OVERWATER!

WEAR SURFACES
ARDEX K-15 is not to be used as a permanent wear surface, even if coated or sealed. ARDEX K-15 must be covered by a suitable floor covering material such as carpet, vinyl flooring, ceramic tile, etc.  For resurfacing and leveling indoor concrete floors in warehouses, storage areas, hallways, or other areas where a wear surface is required, use ARDEX SD-T Self-Drying, Self-Leveling Concrete Topping.

ARDEX TECHNICAL BULLETINS (available upon request from the ARDEX Technical Service Department):

• CSI formatted specifications
• Substrate Preparation with Priming Instructions 
• Hot/Cold Weather Installation Precautions 
• ARDEX K-15 + E-25 Underlayment System over metal subfloors 

ARDEX K-15 UNDERLAYMENT CONCRETE
OVER CUT-BACK AND OTHER ADHESIVE RESIDUES
The ARDEX K-15 + E-25 Underlayment System

INTRODUCTION
Asphalt-based cutback adhesive remaining on a concrete floor after removing old vinyl tile and other flooring represents one of the most difficult and risky subfloors for the installation of new flooring. Bleed-through of the cutback adhesive residue can adversely affect the new adhesive and floor covering being installed.

PROBLEMS
Complete mechanical removal of cutback (i.e. grinding, sanding, blasting) can be hazardous as old cutback adhesive may contain asbestos. Do not sand or grind adhesive residue. Harmful dust may result. Inhalation of asbestos dust may cause asbestosis or other serious bodily harm.  Please consult the adhesive manufacturer and all applicable government agencies for rules and regulations concerning the removal of floorings and adhesives that contain asbestos. Floor covering manufacturers and the Resilient Floor Covering Institute specifically recommend against the use of solvents and adhesive removers to treat adhesive coated subfloors.  Residues from their use have been cited as contributing to numerous floor covering failures. The use of trowelable cementitious patching compounds to mask the presence of adhesive residues can be used successfully, but only when the new adhesive to be used does not react with the old residue, and the floor covering to be installed will not be affected by adhesive bleed-through. 

THE SOLUTION
For 15 years, the ARDEX K-15 + E-25 Underlayment System has allowed the installation of a high-quality concrete underlayment without complete removal of the cutback adhesive down to bare concrete.  This system has been successful on every jobsite when properly installed.

PREPARATION & INSTALLATION
Thick accumulations, powdery, brittle or otherwise weak adhesive layers must be removed, but only with extreme caution.  Use the wet-scraping method as outlined in the Resilient Floor Covering Institute's  "Recommended Work Procedures for Resilient Floor Coverings" to remove thick areas and build-ups of adhesive, and any areas that are weak and not well bonded to the substrate.  (A reproduction of the procedures is available from the ARDEX Technical Service Department.) The remaining residue should appear like a stain on the concrete and should be transparent.  Check the substrate for hollow spots, latex patches or other weak areas and remove them.  Wet-mop the floor to remove all debris and loose material. It is the responsibility of the installation contractor to ensure that the subfloor is properly prepared prior to the installation of the ARDEX material.
Broom and vacuum clean the resulting cutback surface.  Prime the subfloor with ARDEX P-82 Ultra Prime.  Mix Part A (red) with Part B (white) and apply in as thin a layer as possible with a squeegee or a short-nap or sponge paint roller, leaving a thin coat of primer no heavier than a thin coat of paint.  Do not leave any bare spots.  Brush off puddles and excess primer.  Allow to dry for a minimum of 18 hours to a thin, slightly tacky film.
Caution:  ARDEX P-82 should be applied in a thin layer within 1 hour of mixing.  A thick coat will produce a soft, rubbery surface which can result in cracking of  the ARDEX K-15 Underlayment.
Note:  Low surface temperatures and/or high ambient humidity require a longer drying time for ARDEX primers.  Do not install the ARDEX K-15 before the primer has dried thoroughly.
ARDEX K-15 is mixed in 2-bag batches at one time.  For each bag, mix 2 quarts (2 liters) of ARDEX E-25 Resilient Emulsion with 6 quarts (5.5 liters) of water.  Put the liquid in the  ARDEX T-10 Mixing Drum,  then add each bag of ARDEX K-15 powder while mixing at full speed with an ARDEX T-1 Mixing Paddle and a 1/2" heavy-duty drill (min. 650 rpm).  Mix thoroughly for 2 to 3 minutes to obtain a lump-free mixture.  Install at no less than 1/8" thickness over the highest point in the floor, following installation instructions.
When installing material with the ARDEX Levelcraft Automatic Mixing Pump, contact the ARDEX Technical Service Department.
The floor can be walked on in 3 to 4 hours and floor covering can be installed in 16 hours. (Low substrate temperatures and/or high ambient humidity will extend the drying time).

PRECAUTIONS
The ARDEX K-15 + E-25 Underlayment System is intended for application over adhesive residues on concrete subfloors only. Avoid installation over very warm floors (i.e., over hot machine shops or concrete floors containing heating systems, etc.), as heat might soften the remaining residue resulting in failure.
Always install an adequate number of properly located test areas, which include he finish flooring, to ensure the suitability of the system for its intended use.  As floor coverings vary, contact and rely upon the floor covering manufacturer for specific directives, to include requirements such as maximum allowable moisture content, adhesive selection, and intended end use of the product.

OTHER ADHESIVE RESIDUES
The ARDEX K-15 + E-25 Underlayment System is also suitable for installation over any non-water soluble adhesive residue when prepared in accordance with the above recommendations.  Water soluble adhesive residues must be completely removed.  Test installations are always required.

ARDEX K-15 UNDERLAYMENT CONCRETE
OVER WOODEN SUBFLOORS
The Mesh-Reinforced ARDEX K-15 + E-25 Underlayment System

INTRODUCTION
One of the most common problems in renovation and remodeling of existing buildings is the flattening and smoothing of wooden subfloors such as plywood and strip flooring prior to the installation of a new floor covering.

PROBLEMS
Wooden floors move under stress and expand with temperature and humidity changes.  Joints between boards can be very pronounced.  The surfaces are often rough and uneven with deviations up to several inches in ten feet.
Covering these wooden subfloors with a layer of plywood underlayment or other underlayment board is labor-intensive and can result in floor elevation problems at doorways and in hallways.  In addition, if the floor is already uneven, the use of such overlays will not produce a surface which will meet the flooring manufacturer's flatness tolerance.
Traditional latex-modified cement and gypsum patches will crack along joints, break bond with the lateral wood movement, and often disintegrate under traffic stress.

SOLUTION
The Mesh-Reinforced ARDEX K-15 + E-25 Underlayment System is a successful fast-track method which allows the installation of a high-quality concrete underlayment in a thin layer (3/8" minimum), with the strength and flexibility to withstand normal wood movement and traffic stress. The resulting concrete surface is smooth, hard, and suitable for any type of flooring material, including resilient flooring, wood parquet and ceramic tile.

PREPARATION & INSTALLATION
The wooden subfloor must either be solid hardwood flooring or a minimum of 3/4" tongue-and-groove, APA-rated Type 1, Exterior Exposure plywood. The subfloor should be solid and fixed securely to provide a rigid base. Any boards exhibiting movement should be re-nailed.  The surface of the wood must be clean and free of oil, grease, wax, dirt, varnish, shellac, or any contaminant which might act as a bond breaker.  If necessary, sand down to bare wood.  A commercial drum sander can be used to sand large areas.  Do not use solvents, strippers, or cleaners.  Vacuum all dust and debris. Open joints should be filled with ARDEX SD-F Feather Finish Self-Drying, Cement-Based Finishing Underlayment. It is the responsibility of the installation contractor to ensure that the subfloor is thoroughly clean and secure prior to the installation of ARDEX material.
Prime the wooden subfloor with ARDEX P-82 Ultra Prime.  Mix Part A (red) with Part B (white) and apply in as thin a layer as possible with a squeegee or a short-nap or sponge paint roller, leaving a thin coat of primer no heavier than a thin coat of paint.  Do not leave any bare spots.  Brush off puddles and excess primer.  Allow to dry to a thin, slightly tacky film (min. 3 hours, max. 24 hours).
Caution:  ARDEX P-82 should be applied in a thin layer within 1 hour of mixing.  A thick coat will produce a soft and rubbery surface which can result in cracking of the ARDEX K-15 Underlayment.
Note:  Low surface temperatures and/or high ambient humidity require a longer drying time for ARDEX primers.  Do not install ARDEX K-15 Underlayment before the primer has dried thoroughly.
Install 3.4 galvanized, expanded diamond metal lath mesh ("plaster lath") to the subfloor, stapling approximately every 6 inches to prevent the mesh from "floating".  This procedure can be done while the primer is drying by placing the mesh onto a primed area and standing on the mesh while stapling.  Do not walk on the wet primer.  Overlap adjacent pieces of  lath mesh approximately 1". After the mesh has been placed, allow the primer to dry as above. ARDEX K-15 is mixed in 2-bag batches at one time.  For each bag mix 2 quarts (2 liters) of ARDEX E-25 Resilient Emulsion with 6 quarts (5.5 liters) of water. Put the liquid in the ARDEX T-10 Mixing Drum, then add each bag of ARDEX K-15 powder while mixing at full speed with an ARDEX T-1 Mixing Paddle and a 1/2" heavy-duty drill (min. 650 rpm).  Mix thoroughly for 2-3 minutes to obtain a  lump-free mixture.  Install at no less than 3/8" thickness, following installation instructions. When installing material with the ARDEX Levelcraft  Automatic Mixing Pumps, follow installation instructions from the ARDEX Technical Service Department. The floor can be walked on 3-4 hours after installation and floor covering installed in 16 hours. (Low substrate temperatures and/or high ambient humidity will lengthen the drying time). 

PRECAUTION
Always install an adequate number of properly located test areas, which include the finish flooring, to ensure the suitability of the system for its intended use.  As floor coverings vary, always contact and rely upon the floor covering manufacturer for specific directives, to include requirements such as maximum allowable moisture content, adhesive selection and intended end use of the product.

Packaging: 55 lb./25 kg bags.
Storage: Store in a dry area.  Do not expose bags to sun.
Shelf Life: One year.

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