Products : Surface Prep : Mud Bed and Patching Compounds : CUSTOM® SpeedSlope® - Rapid Setting Sloping Mortar

CUSTOM? SpeedSlope? - Rapid Setting Sloping Mortar

SpeedSlope? is a rapid setting, rapid hardening, polymer-modified, pre-blended, cement based mortar bed and sloping mortar for leveling and ramping up to 3" on horizontal substrates; up to 5" thick in confined areas such as trenches. May be also used for walls?and countertops, SpeedSlope? sets to a walkable hardness within one to two hours for installation of ceramic tile & natural stone tile flooring.

Formulated for dimensional stability and exceptional bond strength, SpeedSlope? is ideal for pre-sloping under waterproofing membranes and mortar beds in shower applications, for countertops and patching.

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Key Features

  • Pre-blended, polymer modified mortar bed – just add water and mix
  • Rapid setting – allows tile setting in 1-2 hours
  • Meets requirements of ANSI A108.1
  • Excellent for shower pre-slopes
  • Can be used in wet and dry applications
  • Perfect for deep floor patches
  • Exceptionally smooth finish
  • 4:1 blended cement base suitable for shower receptors


Applicable Standards

American National Standards Institute (ANSI)

  • ANSI A108.1 of the American National Standards for the Installation of Ceramic Tile

ASTM International (ASTM)

  • ASTM C579 Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in.or [50-mm] Cube Specimens)
  • ASTM C627 Standard Test Method for Evaluating Ceramic Floor Tile Installation Systems Using the Robinson-Type Floor Tester

Resilient Floor Covering Institute (RFCI)

  • Recommended Work Practices for Removal of Resilient Floor Coverings

Tile Council of North America (TCNA)

  • TCNA Handbook for Ceramic Tile Installation, TCNA Method EJ171?

Conformance to Building Codes

Installation must comply with the requirements of all applicable local, state and federal code jurisdictions.

Environmental Consideration

Custom? Building Products is committed to environmental responsibility in both products produced and in manufacturing practices. Use of this product may contribute to LEED? certification.

Suitable Substrates

  • Interior or exterior concrete and masonry surfaces
  • Existing finishes and substrates with suitable preparation or priming
  • Exterior grade plywood with lath (dry applications only)
  • RedGard SpeedCoat? Rapid Curing Waterproofing Membrane
  • RedGard??Waterproofing?and?Crack?Prevention?Membrane
  • WonderBoard??Lite,?cement?backerboard units

General Surface Prep

Surfaces must be structurally sound, clean, dry and free from grease, oil, dirt, curing compounds, efflorescence, sealers, adhesives or any other contaminant that would prevent a good bond. Glossy or painted surfaces must be sanded, stripped and cleaned of?waxes, dirt or any contaminants. Concrete must be cured 28 days and accept water penetration. Concrete must not be subject to?hydrostatic pressure. Concrete slabs should have a broomed or brushed finish or be mechanically prepared to enhance the bond. Plywood flooring must be structurally sound and meet all ANSI and deflection requirements. Expansion joints should never be bridged with setting or mortar bed materials. Do not sand flooring materials containing asbestos. Ambient temperature, surfaces and materials should be maintained at a temperature above 50° F (10° C) or below 90° F (32° C) for 72 hours.

Movement Joint Placement

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, such as?CUSTOM's? 100% Silicone. Contact CUSOTM's? Technical Services for the proper treatment of control or saw cut joints. Refer to?TCNA EJ171, F125 and F125A.

Health Precautions

Use proper personal protection equipment including impervious gloves, such as nitrile, dust masks and safety glasses when mixing/handling product.?

This product contains Portland cement and free silica. Avoid eye contact and prolonged contact with skin. Wash thoroughly after handling. If eye contact occurs, flush with water for several minutes and consult a physician. Do not breathe dust; wear a NIOSH approved respirator. Refer to Safety Data Sheet for complete safety information.

Conformance to Building Codes Installation must comply with the requirements of all applicable local, state and federal code jurisdictions.?

Limitations to the Product

  • SpeedSlope? is an underlayment and not recommended as a permanent wear surface
  • Limited to ~30 minutes of working time (roughly 3' x 5' area per placement)
  • Some flooring finishes may require longer cure times to obtain ?lower moisture levels
  • Do not apply directly over wood, metal*, fiberglass, plastic and OSB panels*, lightweight concrete, gypsum underlayment, particle board, hardwood or Parquet floors.
  • *May be installed with use of primers or membranes

Bonding to Concrete Surfaces

For sloping or patching over rough profiled concrete, mix to a plastic consistency up to 4qts water with 50lbs mortar. Scrub coat mixture onto clean, dry concrete surface and apply mortar while scrub coat is still wet. Apply mortar uniformly with pressure to key into the substrate before applying to final finished thickness. Float and/or screed material to appropriate thickness. DO NOT SPONGE OR SPRAY WATER TO SLICK SURFACE AS THIS WILL WEAKEN THE MORTAR SURFACE.

Mortar Beds

Follow ANSI A108.1 A, B or C for the installation of ceramic tile with thick bed mortar. Note: Drying or curing time is affected by ambient and surface temperatures and humidity.

For use as a bonded mortar bed, mix to a semi-damp, dry pack consistency using 2.5-3.0 qts water to 50lb mortar. Scrub coat or trowel a wet mixture bond coat (4qts water with 50lbs mortar) onto concrete surface and apply dry pack mortar while scrub coat is still wet. Compact SpeedSlope? well to form the mortar bed and trowel surface.? For non-bonded applications over cleavage membranes, assure wire reinforcing or lath is used per ANSI A108 methods.


Surface Bonded Waterproofing – B421

Download the illustrated installation details by clicking on the link above or go to, select “Tile” as the installation type and select the appropriate illustrated TCNA detail by number (example: B414).

Bonding to Plywood Surfaces

Plywood floors, including those under resilient flooring, must be structurally sound and must meet all ANSI A108.01 Part 3.4 requirements. Follow TCNA F141 or F145 guidelines for the installation of the thick bed mortar over plywood sub floor.?

Mixing Procedures

Drypack - Combine 50lbs of SpeedSlope? powder with 2.5-3.0 quarts of water in a clean mixing vessel. Mix material until all powder is thoroughly wet out and uniform. Material should be free of clumps and hold shape when squeezed together by hand.

Plastic Sloping Mortar – Combine 50lbs of SpeedSlope? powder with 3.5-4.0 quarts of water in a clean mixing vessel and mix to a uniform lump free consistency. Mix with a Hole Hawg with a square cage mixing paddle until lump free - approximately 2 minutes. High gear is needed to properly mix dry-pack and plastic consistencies. Alternatively a mortar mixer may be used with typical mix times of 2-3 minutes, but do not over mix. Rinse paddle between batches.

Application of Product

Prior to application to absorptive substrates, damp sponge the area to prevent excessive moisture loss to the substrate. Do not saturate the surface or leave standing water. Alternatively, porous substrates may be primed using CUSTOM? MBP? or TechPrime A? or other approved CUSTOM? primer according to their respective directions.?

Curing of Product

  • Tile installations* – 60 minutes
  • CUSTOM RedGard??Waterproofing -60 minutes
  • CUSTOM RedGard? SpeedCoat – 60 minutes
  • Moisture Sensitive Flooring – 6 -12 hours
  • Foot traffic – 2-3 Hours
  • Light Trade Traffic – 4 hours
  • Vehicular Traffic – 12 Hours

?????? *Moisture sensitive tiles or natural stone may require longer cure times.

Cleaning of equipment

Clean with water before material dries.

Handling & Storage

Store in a cool dry area.

Product Maintenance

Properly installed product requires no special maintenance.

Ordering Information


50 lb (22.68 kg) Bags

Warranty Information

Product Warranty

Obtain the applicable LIMITED PRODUCT WARRANTY at or send a written request to Custom Building Products, Inc., Five Concourse Parkway, Atlanta, GA 30328, USA. Manufactured under the authority of Custom Building?Products,?Inc.???2017?Quikrete?International,?Inc.

Coverage Chart

  • 50 lbs (0.5 cu ft) will cover 5 ft2 @1" thickness
  • Five to six 50lb bags will complete a mortar bed for 3'x5' shower base

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