SpecChem > Products > Repair Mortars > SpecPatch 15

SpecPatch 15

Fast-setting polymer-modified concrete repair material

SpecPatch 15 is a versatile, polymer-modified concrete repair mortar ideal for restoring concrete floors, walls, precast structures, tilt-up, and masonry surfaces. It is suitable for both indoor and outdoor use, providing a durable solution that can be finely adjusted by shaving or sanding to meet repair needs.

  • Lifts up to 1″ in thickness
  • Designed for interior & exterior repairs
  • Dries to the color of concrete
  • Can be feather-edged and shaped
  • One-component — just add water
  • Excellent durability and adhesion

Tech Sheet
Safety Sheet



  • Suitable for interior and exterior environments
  • Applicable to vertical, overhead, and horizontal repairs
  • Ideal for no slump consistency applications
  • Excellent for repairing concrete pipes, curbs, sidewalks, and precast concrete

Surface Preparation: The concrete must be in good condition, free from oil, grease, dust, laitance, or other contaminants. Maximizing durability involves saw cutting the repair perimeter 1/8” deeper than the repair depth to create a notched, reinforced edge. Surfaces should be mechanically abraded to a minimum Concrete Surface Profile (CSP) of 5 in accordance with the ICRI 310.2 Guideline. All surfaces must be saturated-surface-damp (SSD) with no standing water.

Priming/Scrub Coat: Clean exposed steel reinforcing from rust and apply SpecPrep SB. The prepared concrete surface must be SSD and primed with SpecPrep SB, applying the repair mortar wet on wet or within the primer’s open time. Alternatively, a scrub coat of the mixed mortar can be applied to ensure strong adhesion.

Mixing Instructions: Mix 6.75 – 7.25 pints of clean water per 50-pound bag of SpecPatch 15, adjusting water volume based on the desired consistency. Use a low-speed drill for mixing, beginning with water then adding SpecPatch 15, and mix for 2-3 minutes. Prepare only the amount that can be used within the working time. Mixing with SpecChem StrongBond Acrylic Bonder, neat or diluted, is advised for enhanced durability, especially in thin, heavily trafficked areas.

Application: Trowel SpecPatch 15 into the repair area, ensuring full contact with the substrate. Overfill slightly, then shape to the desired contour after initial set but while still workable. Apply in layers up to 1” thick, roughening between layers to enhance bonding.

Finishing/Curing: Texture the repair to match the surrounding concrete. Under most conditions, SpecPatch 15 is self-curing. In very dry conditions, use a water-based curing compound compliant with ASTM C309.

Shelf Life

Unopened bags have a 12-month shelf life in dry conditions. Store in a cool, dry place away from sunlight.

Test Data

Technical Specifications:

  • Initial set time of 15 – 30 minutes and final set in 60 minutes at 70°F, following ASTM C266 standards.
  • Compressive strength reaches 1200 psi in 3 hours, peaking at 6200 psi over 28 days.
  • Exhibits minimal shrinkage and outstanding freeze-thaw resistance with no scaling after 25 cycles.
  • Slant shear bond strength of 1620 psi after 7 days and flexural strength of 650 psi at 28 days.