Repair Systems — Concrete & Structural Defects

Polymer-modified repair mortars

Technical product reference for polymer-modified cementitious repair mortars used to reinstate concrete cover over cleaned and primed reinforcement in corrosion repair — EN 1504-3 classified, thixotropic, suitable for overhead and vertical application in Australian structural repair.

4
Products covered
EN 1504-3
Classification
Overhead / Vertical
Application
R3 / R4 mortar
Types

Polymer-modified repair mortars in reinforcement corrosion repair

Polymer-modified repair mortars are the primary material used to reinstate the concrete cover over cleaned and primed reinforcement in structural and cosmetic patch repair. They are classified under EN 1504-3 from R1 (cosmetic, non-structural) to R4 (structural, high compressive strength). Thixotropic formulations allow overhead and vertical application by hand without sagging, which is essential for soffit repair on elevated carparks and balconies.

Product Reference

Individual products — one card each — scroll to view all

11 products2 visible, scroll for more

Sika Australia

Sika MonoTop-352NFG

Polymer-modified, fibre-reinforced structural repair mortar

Sika MonoTop-352NFG is the general-purpose, fibre-reinforced, polymer-modified structural repair mortar in the MonoTop range — EN 1504-3 Class R3, tested ~30 MPa @28d. Applied up to 75 mm per layer on vertical and overhead surfaces with a built-in corrosion inhibitor; no bonding primer is required on a well-prepared, roughened substrate.

EN 1504-3 · R3StructuralGeneral-purposeVertical · Overhead4–75 mm

Sika Australia

Sika MonoTop-612N

Polymer-modified high-build structural repair mortar

Sika MonoTop-612N is the high-build EN 1504-3 Class R4 structural repair mortar in the MonoTop range — tested ~70 MPa @28d — for deep spall reinstatement in a single layer up to 100 mm on vertical and overhead surfaces. It has no integral corrosion inhibitor and is intended for use with external Sika FerroGard inhibitors / anodes where rebar protection is required.

EN 1504-3 · R4StructuralHigh-buildVertical · Overhead5–100 mm

Sika Australia

Sika MonoTop-412NFG

Polymer-modified structural repair mortar with corrosion inhibitor

Sika MonoTop-412NFG is an EN 1504-3 Class R4 structural repair mortar (not a fine / cosmetic mortar) with a built-in corrosion inhibitor — tested ~50 MPa @28d — applied up to 50 mm per layer on vertical and overhead surfaces. For a 0–3 mm cosmetic fairing coat, Sika MonoTop FC is the correct separate product.

EN 1504-3 · R4StructuralGeneral · StructuralVertical · Overhead6–50 mm

ARDEX Australia

ARDEX BR 340

MICROTEC fibre-reinforced, polymer-modified structural repair mortar

ARDEX BR 340 is a MICROTEC fibre-reinforced, polymer-modified structural repair mortar — EN 1504 R3, tested 30–40 MPa @28d — applied 10–80 mm on vertical, horizontal and overhead surfaces with an active corrosion inhibitor. It is low-resistivity (compatible with ARDEX BRX 60 LO galvanic anodes). Prime the substrate with ARDEX WR Prime (wet-on-wet) and rebar with BR 10 ZP — not ARDEX P 51 (a flooring primer).

EN 1504 · R3StructuralGeneral-purposeV / H / Overhead10–80 mm

ARDEX Australia

ARDEX BR 345

High-resistivity MICROTEC fibre-reinforced structural repair mortar

ARDEX BR 345 is the high-resistivity (>15,000 Ω·cm) variant of the BR structural repair mortar — EN 1504 R3, tested 30–45 MPa @28d, AS/NZS 4020 potable-water compliant — applied 10–80 mm on vertical, horizontal and overhead surfaces with an active corrosion inhibitor. Because of its high resistivity it must NOT be used with ARDEX BRX 60 LO galvanic anodes. Prime with ARDEX WR Prime + BR 10 ZP on rebar.

EN 1504 · R3StructuralHigh-resistivityV / H / Overhead10–80 mm

Fosroc / Parchem

Fosroc Renderoc HB

Hand-applied polymer-modified structural repair mortar

Fosroc Renderoc HB is a general-purpose hand-applied, polymer-modified structural repair mortar distributed by Parchem — tested 28 MPa @28d (AS 1478.2) — applied up to 80 mm vertical / 50 mm overhead per layer. It is reported to Australian Standards only (no EN 1504-3 class — specify HB40 where an R3 classification is required). Prime the substrate with Nitobond HAR and rebar with Nitoprime Zincrich.

AS-tested · no EN classStructuralGeneral · High-buildVertical · Overhead10–80 mm

Fosroc / Parchem

Fosroc Renderoc HB40

EN 1504-3 R3 high-strength polymer-modified repair mortar

Fosroc Renderoc HB40 is the EN 1504-3 Class R3 member of the Renderoc high-build range — tested 38 MPa @28d (EN 12190), with pull-off bond 1.8 MPa (no primer) or 2.5 MPa with Nitobond HAR — applied up to 40 mm per layer. It is compatible with Galvashield galvanic anodes. Specify HB40 where an R3 classification is required.

EN 1504-3 · R3StructuralHigh-strengthVertical · Overhead10–40 mm

Fosroc / Parchem

Fosroc Renderoc FC

Fine cosmetic fairing coat (non-structural)

Fosroc Renderoc FC is the fine cosmetic fairing coat of the Renderoc range — a 0–3 mm featherable polymer mortar for blowholes, bug-holes and surface profiling over a completed, sound structural repair. Working life ~20 min. It is not a structural repair mortar and must not be used to reinstate concrete cover.

Fairing coat · no EN classCosmetic — non-structuralFine finishThin section0–3 mm

Mapei Australia

Mapei Mapegrout T40

Thixotropic polymer-modified R3 structural repair mortar

Mapei Mapegrout T40 is a thixotropic, fibre-reinforced, polymer-modified EN 1504-3 Class R3 structural repair mortar — tested >40 MPa @28d, AS/NZS 4020 potable-water compliant — applied ~30–35 mm per layer on vertical and overhead surfaces. Adhesion (>2 MPa, EN 1542) is achieved on a roughened, saturated (SSD) substrate with no bond coat; treat exposed rebar with Mapefer.

EN 1504-3 · R3StructuralGeneral · ThixotropicVertical · Overheadto 35 mm

Mapei Australia

Mapei Mapegrout T60

R4 sulphate-resistant fibre-reinforced repair mortar

Mapei Mapegrout T60 is an EN 1504-3 Class R4, sulphate-resistant, fibre-reinforced repair mortar with integral organic corrosion inhibitors — tested 60 MPa @28d — applied up to 100 mm vertical (multi-coat) or 20 mm overhead. Bond >2 MPa (EN 1542) on a roughened, saturated (SSD) substrate; treat exposed rebar with Mapefer.

EN 1504-3 · R4StructuralHigh-buildVertical · Overhead10–100 mm

Fosroc / Parchem

Fosroc Renderoc G

Geopolymer acid / chemical-resistant repair & lining mortar

Fosroc Renderoc G is a geopolymer acid / chemical-resistant repair and lining mortar (fumed silica + slag + fly ash) for aggressive exposure — sewers, acid bunds and processing plants — not a default polymer-modified spall mortar. Tested 35 MPa @28d; retains 26 MPa after 8 weeks in 20% sulphuric acid. Certified to Australian Standards only (no EN class).

AS-tested · no EN classSpecialist — geopolymerAcid / chemical resistantVertical · Overhead10–80 mm

System Comparison

Polymer-modified repair mortars — confirm all selections against the current manufacturer TDS before specifying.

Scroll the table sideways to see every column →

ProductThickness (min layer)Max build / passSubstratePrimer / bond coatApplication methodApplication tempPot lifeVertical / overheadFine finish
Sika MonoTop-352NFGSika Australia4 mm75 mmRoughened, pre-wetted (SSD)None required on well-prepared substrateHand / trowel applied+5 to +30 °CInitial set ~3 hYes (thixotropic)No — use MonoTop FC (0–3 mm)
Sika MonoTop-612NSika Australia5 mm100 mmRoughened, pre-wetted (SSD)None required on well-prepared substrateHand / trowel applied+5 to +30 °C~35 min @23°CYes (thixotropic)No — use MonoTop FC (0–3 mm)
Sika MonoTop-412NFGSika Australia6 mm50 mmRoughened, pre-wetted (SSD)None required on well-prepared substrateHand / trowel applied+5 to +30 °C~40 minYes (thixotropic)No — structural; use MonoTop FC for fairing
ARDEX BR 340ARDEX Australia10 mm80 mmSSD — ARDEX WR Prime wet-on-wetARDEX WR Prime + BR 10 ZP (rebar)Hand / trowel applied5 to 35 °C45–90 minYes (V / H / OH)No — use a fairing product
ARDEX BR 345ARDEX Australia10 mm80 mmSSD — ARDEX WR Prime wet-on-wetARDEX WR Prime + BR 10 ZP (rebar)Hand / trowel applied5 to 35 °C45–90 minYes (V / H / OH)No — use a fairing product
Fosroc Renderoc HBFosroc / Parchem10 mm80 mm vert / 50 mm OHRoughened, saturated (SSD)Nitobond HAR + Nitoprime Zincrich (rebar)Hand / trowel applied5 to 35 °CInitial set 2–3 hYes (80 V / 50 OH)No — use Renderoc FC
Fosroc Renderoc HB40Fosroc / Parchem10 mm40 mmRoughened, saturated (SSD)Nitobond HAR (or none — 1.8 MPa bond)Hand / trowel applied5 to 35 °CInitial set 2–3 hYesNo — use Renderoc FC
Fosroc Renderoc FCFosroc / ParchemFeather edge3 mmRoughened, saturated (SSD)Per Renderoc system — refer to current TDSHand / trowel applied5 to 35 °C~20 min working lifeYes (thin section)Yes — this is the fine finish
Mapei Mapegrout T40Mapei AustraliaN/A30–35 mmRoughened, saturated (SSD)None — SSD substrate; Mapefer on rebarHand / trowel applied+5 to +35 °C~60 min @20°CYes (thixotropic)No — use Planitop Fine Finish
Mapei Mapegrout T60Mapei Australia10 mm100 mm vert / 20 mm ceilingRoughened, saturated (SSD)None — SSD substrate; Mapefer on rebarHand / trowel applied+5 to +35 °C~60 min @20°CYes (thixotropic)No — use Planitop Fine Finish
Fosroc Renderoc GFosroc / Parchem10 mm80 mm vert / 50 mm OHSSD — saturated 2–3 hNitoprime Zincrich (rebar); no bonding slurryHand / trowel applied5 to 35 °CRapid set — ~3 min mixYes (80 V / 50 OH)N/A

Do not confuse polymer-modified repair mortars with:

  • Epoxy repair mortars — epoxy-based repair mortars (different product class to polymer-modified cementitious mortars) are used for high-strength, chemically resistant, or thin-section repairs; they have different mixing, application, and performance characteristics — do not substitute
  • Render and plaster products — proprietary renders and finishing plasters are not EN 1504-3 classified repair mortars; they do not meet the bond, compressive strength, or durability requirements for structural concrete repair
  • Bonding agents — SBR latex and acrylic bonding agents are applied to the substrate before repair mortar; they are not repair mortars themselves and cannot substitute for the repair mortar in the repair sequence
  • Rebar primers — epoxy zinc-rich primers and cementitious rebar coatings are applied to the rebar before repair mortar is placed; they are a separate preceding step, not part of the mortar itself
  • General-purpose cement mortars — site-batched cement:sand mortars do not meet EN 1504-3 requirements for structural repair — use only EN 1504-3 classified repair mortars in structural repair

Disclaimer

This page provides general technical information only. Final product selection must be confirmed against the current manufacturer TDS, project specification, and EN 1504-3 class required by the engineer. Do not rely on this reference as a substitute for professional engineering advice.

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