ARDEX-N-23 Rapid Set Natural Stone and Tile Mortar Instructions

: June 13, 2024
: ARDEX

Table of Contents

ARDEX-N-23 Rapid Set Natural Stone and Tile Mortar
Product Information
Product Using Instructions
Features
Using Instructions
Existing Tiles and Other Non-Porous Surfaces
- Safety and OSHA Compliance
ARDEX Tile and Stone Mortar Usage Guide
Technical Data
Contact
References
Read User Manual Online (PDF format)
Download This Manual (PDF format)

ARDEX-N-23 Rapid Set Natural Stone and Tile Mortar

Product Information

The Rapid Set Natural Stone and Tile Mortar is specifically designed for installing moisture-sensitive natural stone, marble, and granite, including mosaics. It can be used on plywood and other interior surfaces without causing discoloration, efflorescence, or warping. This mortar is suitable for various substrates, including concrete, plywood, and existing tiles. It is also suitable for the installation of most common tile types.

Suitable Substrates

All common building substrates (concrete that has cured for at least 28 days, plywood in interior, horizontal applications, CBU in accordance with manufacturer guidelines, etc.)
Existing tiles (tile over tile)
Metal (Interior only and non-aluminum. Contact ARDEX Technical Service for instructions.)
Some substrates require priming.

Suitable Applications

The Rapid Set Natural Stone and Tile Mortar can be used for the installation of most common tile types.
For highly absorbent tile or resin-backed tiles and stone, it is recommended to contact ARDEX Technical for specific instructions.

Product Using Instructions

Job Conditions

Before starting the installation process, it is important to properly prepare the substrate. This includes mechanically cleaning the substrate using shot blasting or similar means. Acid etching, adhesive removers, solvents, and sweeping compounds should not be used as they can break the bond. Sanding is also not recommended for concrete contaminants removal.

All substrates must be sound, solid, and thoroughly clean of all existing patching and leveling materials, as well as any bond-breaking contaminants such as overwatered or weak material, unapproved sealers, and adhesive residues. Thorough vacuuming should be done to remove excess dirt and debris. For detailed instructions on proper substrate preparation, refer to the articles on Proper Prep available at ardexamericas.com/properprep. These articles cover preparing concrete for bonded ARDEX or HENRY applications and preparing wood for bonded ARDEX applications.

The plane of wall surfaces must be plumb and true, while floor surfaces should have minimal variation in the plane or slope according to the Tile Council of North America (TCNA) guidelines. ANSI A108.01 General Requirements: Subsurface and Preparation by Other Trades and the most current version of the TCNA Handbook for Ceramic Tile Installation should be consulted for detailed information on surface preparation and substrate construction guidelines.

Pre-Leveling / Smoothing Options (if needed)

If necessary, follow the substrate preparation, mixing, application, and drying instructions provided in the appropriate ARDEX technical data sheet. Expansion joints should be provided over existing moving joints and cracks, as well as where substrate materials change composition or direction, as per ANSI A 108 AN-3.7.

Waterproofing / Crack Isolation/ Uncoupling; Priming / Treating Certain Substrates (if needed)

If waterproofing, crack isolation, or uncoupling is required for interior applications, follow the instructions provided in the respective technical data sheet.
For metal substrates, contact the ARDEX Technical Service Department for specific application instructions over interior, non-aluminum metal substrates.
If applying over existing tiles or other non-porous surfaces, one option is to apply a coat of ARDEX P 4TM Pre-Mixed, Rapid Drying, Multipurpose Primer. This primer must dry for 30 – 60 minutes before proceeding with the tile installation.

Install moisture-sensitive natural stone, marble and granite, including mosaics, over plywood and other interior surfaces without discoloration, efflorescence or warp.

Features

Use for setting porcelain, quarry and ceramic tile, mosaics, ungauged stone, translucent marble, glass and natural stone tile
Fast setting – grout in 2 hours
Self-drying technology
Ideal for use with moisture-sensitive tile and stone; will not contribute to staining, efflorescence or warping
Outstanding coverage – 103 sq. ft. (9.5 sq. m) per bag with 1/4” sq. notch trowel
Thin to medium or bed installation up to 5/8” (15 mm)
1-hour pot life
Use for interior floors and walls
Extended open time of 30 minutes
Excellent bond strength and sag resistance
Available in 40 lb. bags (gray or white)
Meets or exceeds ANSI 118.5. For interior use only

Suitable Substrates

All common building substrates (concrete that has cured for at least 28 days, plywood in interior, horizontal applications, CBU in accordance with manufacturer guidelines, etc.)
Existing tiles (tile over tile)
Metal (Interior only and non-aluminum. Contact ARDEX Technical Service for instructions.)

Some substrates require priming.

Suitable Applications

Interior Only; 50 – 85 °F (10 – 29° C)
- Dry or damp substrates (no standing water)
- Interior (not submerged)
Installation of most common tile types:
- Contact ARDEX Technical for highly absorbent tile
- Contact ARDEX Technical for resin-backed tiles and stone

Job Conditions

During installation and cure, substrate and ambient temperatures must be a minimum of 50°F / 10°C .

Using Instructions

Step 1: Substrate Preparation (Proper Prep™)

If necessary, mechanically clean the substrate by shot blasting or similar means. Do not use acid etching, adhesive removers, solvents or sweeping compounds, as these are bond breakers. Sanding is not an effective method to remove contaminants from concrete. All substrates must be sound, solid and thoroughly clean of all existing patching and leveling materials and all bond- breaking contaminants, including but not limited to: overwatered or otherwise loose or weak material; unapproved sealers ; all adhesive residues.

Vacuuming

Following preparation, thoroughly vacuum to remove all excess dirt and debris.

For full details on Proper Prep, reference the following articles at ardexamericas.com/properprep:

Article 1: Preparing Concrete for Bonded ARDEX or HENRY Applications
Article 2: Preparing Wood for Bonded ARDEX Applications
Proper Prep Brochure

The plane of wall surfaces must be plumb and true. Floor surfaces must have minimal variation in the plane or slope as outlined by the Tile Council of North America (TCNA). Refer to ANSI A108.01 “General Requirements: Subsurface and Preparation by Other Trades” and the most current version of the TCNA “Handbook for Ceramic Tile Installation” for detailed information on surface preparation and guidelines for substrate construction.

Step 2: Pre-Leveling / Smoothing Options (if needed)

ARDEX AM 100™ Rapid Set Pre-Tile Smoothing and Ramping Mortar
ARDEX A 38™ Rapid Set Screed
ARDEX Liquid BackerBoard® Self-Leveling Underlayment for
Interior Wood and Concrete Subfloors
ARDEX TL 1000™ Self-Leveling Underlayment
ARDEX TL 1400™ Self-Leveling Underlayment
ARDEX TL 2000™ Fiber Reinforced, Self-Leveling Underlayment
ARDEX SKM™ Skim Finish – Skimcoat Patch & Finishing Underlayment

Observe the substrate preparation, mixing, application and drying instructions in the appropriate ARDEX technical data sheet. Per ANSI A 108 AN-3.7, expansion joints must be provided over existing moving joints and moving cracks and where substrate materials change composition or direction.

Step 3: (if needed) Waterproofing / Crack Isolation/ Uncoupling; Priming / Treating Certain Substrates

Note: Membrane application limits the allowable mortar thickness. See “Maximum Mortar Thickness over Membranes” under “Step 4,” below.

Waterproofing / Crack Isolation Options (Interior Only)

ARDEX 8+9™ Rapid Waterproofing and Crack Isolation Compound
ARDEX S 1-K™ One-Component Waterproofing and Crack Isolation Membrane
ARDEX FLEXBONE® HEAT In-Floor Heating Systems
ARDEX UI 740™ FLEXBONE® Uncoupling Membrane
ARDEX UI 720™ FLEXBONE® Floating Uncoupling Membrane
Follow the instructions in the respective technical data sheet.

Metal Substrates

Contact the ARDEX Technical Service Department for application instructions over interior, non-aluminum metal substrates.

Existing Tiles and Other Non-Porous Surfaces

Option 1: Apply a coat of ARDEX P 4™ Pre-Mixed, Rapid- Drying, Multipurpose Primer, which must dry 30 – 60 minutes before proceeding with the tile installation.
Option 2: (interior, dry applications only): Mix the mortar with ARDEX E 90 ™ Admix in accordance with the technical data sheet, and install directly over the non-porous surface.

Gypsum (interior only)

Option 1: Apply a coat of ARDEX P 4, as directed above.
Option 2: Double prime with ARDEX P 51™ Primer, as detailed in the technical data sheet.

Other Highly Absorbent Substrates (plaster, etc.)

Option 1: Apply a scratch coat of the tile mortar. Allow the scratch coat to harden and dry completely before proceeding with the tile installation.
Option 2: Apply a coat of ARDEX P 4, as directed above.
Option 3: (interior, dry applications only): Double prime with ARDEX P 51™ Primer, as detailed in the technical data sheet.

Step 4: Mixing and Application

Recommended Tools

Margin trowel • Mixing container • ARDEX T-2 Ring Mixing Paddle • 1/2″ (12 mm) heavy-duty drill (min. 650 rpm) • Appropriate notched trowel

Maximum Mortar Thicknesses Over Membranes

Membrane Type	Max. Thickness	Max. Trowel Notch Size

Unbonded uncoupling

membranes:

| 1/4” (6 mm)| 1/2” x 1/2”

(12 mm x 12 mm)

All other membranes:| 3/8” (9.5 mm)| 3/4” x 3/4”

(19 mm x 19 mm)

Safety and OSHA Compliance

Handle each bag with care, emptying it in a manner that avoids creating a plume of dust. While mixing, use a standard “gutter hook” vacuum attachment in combination with a heavy-duty, bucket-style vacuum (Shop-Vac® or similar) and HEPA dust extraction vacuum system.

Application Data

Times based on 70°F / 21°C.

Water ratio:| 6 1/4 – 6 3/4 quarts (6.0 – 6.5 L) of clean water per bag; or 2.5 parts powder to 1 part water by volume (small batches)
---|---
Pot life:| 60 minutes
Open time:| Up to 30 minutes
Adjustment time:| 15 minutes

Pour the water in the mixing container first, and then add powder while mixing for 2 to 3 minutes. For best results for full-bag batches, mix with an ARDEX T-2 Ring Mixing Paddle and 1/2” heavy-duty drill (12 mm, min. 650 rpm) and mixing paddle. DO NOT ADD MORE WATER! Additional water will weaken the compound and lower its strength.

Small batches may be mixed by hand. Use a margin trowel, and mix vigorously. Just prior to application on the substrate, the mixture should be stirred again to ensure a creamy, smooth, lump-free consistency. Jobsite conditions and temperature may affect pot life. If the material begins to harden within published pot life, retemper with a drill.

Installation should proceed in accordance with ANSI A 108.5. After mixing, apply mortar to the substrate with the flat side of a trowel to obtain a solid mechanical bond. Apply to an area no greater than that which can be covered with tile while the mortar remains plastic. Do not set tile or stone into skinned over mortar. Comb the mortar with a notched trowel of sufficient depth to ensure that the tile or stone is covered uniformly over the entire surface. Follow TCNA recommendations for proper transfer of mortar from the substrate to the tile or stone. The type and size of the tile or stone will dictate the size of the notched trowel to be used to achieve proper transfer.

When setting certain types of tile or stone, it may be necessary to trowel a layer of mortar on the back of each tile or stone prior to placement on the combed mortar bed in order to achieve the required mortar-to-tile contact. Press each tile firmly into the freshly combed mortar to ensure maximum mortar contact with the tile. In order to avoid irregular marks in translucent natural stone installations, it is recommended that a scratch coat of ARDEX N 23 White be applied to the back of the tile.

Step 5: Grouting Instructions and Options

All dry times are calculated at 70°F (21°C). Drying time is a function of jobsite temperature and humidity conditions. Low substrate temperatures and/or high ambient humidity will extend the drying time. Adequate ventilation and heat will aid drying.

Cure time prior to grouting: 2 hours

ARDEX FL™ Rapid Set, Flexible, Sanded Grout
ARDEX FH™ Sanded Floor and Wall Grout
ARDEX FG-C™ MICROTEC® Unsanded Floor & Wall Grout
ARDEX WA™ High-Performance, 100% Solids Epoxy Grout and Adhesive

Grout in accordance with the respective technical data sheet and ANSI A 108.10.

Notes

FOR PROFESSIONAL USE ONLY by licensed, bonded contractors who are trained in the application of this product and/or similar products. Not sold by ARDEX through home improvement centers. For information on ARDEX Academy trainings, visit ardexamericas.com.
In accordance with industry standards, and to determine the suitability of the products for the intended use, always install an adequate number of properly located test areas, including the tile flooring. As tiles vary, always contact and rely upon the tile manufacturer for specific directives, such as maximum allowable moisture content, mortar selection and intended end use of the product.
Never mix with cement or additives outside of our written recommendations. Observe the basic rules of concrete work, including the minimum surface and air temperatures detailed above. Install quickly if the substrate is warm, and follow the warm weather installation guidelines available on our website. Observe the basic rules of tile work.
Dispose of packaging and residue in accordance with prevailing regulations. Do not flush material down drains. Do not reuse packaging.

ARDEX Tile and Stone Mortar Usage Guide

Moisture-sensitive natural stone or agglomerate tile (interior, dry applications only):

ARDEX X 32™ MICROTEC® Universal Rapid Setting and Drying Thin-to-Thick Bed Mortar
ARDEX S 28™ MICROTEC® Rapid-Set, Rapid-Dry, Super- Format Tile and Uncoupling Membrane Mortar
ARDEX N 23™ MICROTEC® Rapid Set Natural Stone and Tile Mortar

Saltwater pools; glass tiles in swimming pools and other submerged areas:

ARDEX WA™ High-Performance, 100% Solids Epoxy Grout and Adhesive

Glass tiles at pool splash lines:

ARDEX X 77™ MICROTEC® Fiber Reinforced Tile and Stone Mortar WHITE mixed with ARDEX E 90™ Admix
Glass tiles in non-submerged areas:
- ARDEX X 77™ MICROTEC® Fiber Reinforced Tile and Stone Mortar (interior or exterior applications)
- ARDEX S 48™ Rapid-Set Thin Set Mortar/ Mastic Hybrid (Interior applications only)

Balconies, terraces and building facades that experience a great deal of movement due to temperature changes:

ARDEX X 90 OUTDOOR™ MicroteC3 Rapid-Set, Flexible Tile and Stone Mortar
ARDEX X 77™ MICROTEC® Fiber Reinforced Tile and Stone Mortar
ARDEX X 78™ MICROTEC® Fiber Reinforced, Semi-Pourable, Polymer Modified Tile and Stone Mortar

Technical Data

Technical Data According to ARDEX Quality Standards

All data based on a partial, in-lab mix. Mixing and testing completed at 70°F / 21°C Physical properties are typical values and not specifications.

Coverage:| 1/4” x 1/4” (6 mm) sq. notch trowel = 103 ft² (9.5m²) per bag

1/4” x 3/8” (6 mm x 9 mm) sq. notch trowel = 80 ft² (7.4 m²) per bag

1/2” x 1/2” (12 mm) sq. notch trowel =

57.5 ft² (5 m²) per bag

Coverage varies with texture of substrate surface.

---|---
Colors:| Gray and white
VOC:| 0
Packaging:| 40 lb (18 kg) bag
Storage:| Store in a cool, dry area. Do not leave units

exposed to sun.

Shelf Life:| 1 year, if unopened and properly stored
Warranty:| ARDEX L.P. Standard Limited Warranty applies. Also eligible for ARDEX SystemOne® Warranty when used in conjunction with select ARDEX tile and stone installation materials. See ardexamericas.com/services/warranties for full warranty details.

ISO 13007 Classification Classification Requirements

C2 (cementitious, improved adhesion)| ≥ 145 psi (1 MPa/10.2 kg/ cm2) after standard aging, heat aging, water immersion and

freeze/thaw cycles

T (vertical slip resistance)| ≤ 0.019” (0.5 mm)
E (extended open time)| ≥ 72.5 psi (0.5 MPa/5 kg/cm2) after 20 – 30

minutes

F (fast setting)| ≥ 72.5 psi (0.5 MPa/5 kg/cm2) at 6 hours
S1 (normal deformation of mortar)| ≥ 0.1” (2.5 mm) <0.2” (< 5mm)

28-day test| Test Method| ANSI

Specification

| Test Results

483 psi (3.3 MPa/33.8

kg/cm²)

---|---|---|---
Impervious ceramic (porcelain) mosaics shear strength| ANSI A118.4| ≥200 psi (1.38 MPa/14 kg/cm2)
Glazed wall tile shear strength| ANSI A118.4| >300 psi (2.07 MPa/21.0

kg/cm²)

| 450 psi (3.1 MPa/31.5

kg/cm²)

Quarry tile to plywood shear strength| ANSI A118.11| >150 psi (1 MPa/10.5

kg/cm²)

| 216 psi (1.49 MPa/15.1

kg/cm²)

MPa/28 kg/cm²)

| 669 psi (4.61 MPa/47.0

kg/ cm²)

Impervious ceramic (porcelain) mosaics shear strength with freeze-thaw cycling| ANSI A118.15| >250 psi (1.73 MPa/17.5

kg/cm²)

| 620 psi (4.27 MPa/48.9

kg/cm2)

Impervious ceramic (porcelain) mosaics shear strength with heat aging| ANSI A118.15| >400 psi (2.76

MPa/28 kg/cm²)

| 695 psi (4.79 MPa/36.34

kg/cm²)

Glazed wall tile shear strength| ANSI A118.15| >450 psi (3.11 MPa/31.5

kg/cm²)

| 539 psi (3.72 MPa/37.9

kg/cm²)

Quarry tile shear strength| ANSI A118.15| >150 psi (1 MPa/10.5

kg/cm²)

| 362 psi (2.5 MPa/25.5

kg/cm²)

Quarry tile to plywood shear strength| ANSI A118.11| >150 psi (1 MPa/10.5

kg/cm²)

| 258 psi (1.78 MPa/18.1

kg/cm²)

7-day test /Test Method /ANSI Specification /Test Results

Impervious ceramic (porcelain) mosaics shear strength with water immersion/ ANSI A118.15 F/ ≥200 psi (1.38 MPa/14 kg/cm2)/ 453 psi (3.12 MPa/32.0 kg/cm²)

Contact

Visit www.youtube.com/ARDEX101 to watch ARDEX product demonstration videos. For recommended installation tools, visit DTA USA at www.dtausagroup.com. For easy.to-use ARDEX Product Calculators and Product Information On the Go, download the ARDEX App.

ARDEX Americas