Repair Systems
Sealants (polyurethane)
1-part polyurethane flexible joint sealant — technical reference for concrete cracking in Australian remedial building practice. Covers system selection, product comparisons, and brand equivalents.
What is sealants (polyurethane)?
Polyurethane sealants are flexible, movement-accommodating joint compounds used to seal construction joints, control joints, perimeter gaps, and dynamic cracks in concrete, masonry, and facade systems. In remedial building work they are specified to reinstate deteriorated joint sealant that has cracked, debonded, or lost elasticity, allowing water to penetrate into building structure and causing subsequent damage. Most products accommodate ±25–35% of joint width in movement and are paintable once cured, making them the default choice for restoration work where the finished appearance must match surrounding surfaces. Joint preparation — removing all existing sealant, priming the substrate, and installing a correctly sized backer rod — is as important as product selection for achieving a long service life. Widely used by waterproofing contractors, facade engineers, and remedial building practitioners.
Product Reference
Scroll right to see all brands. Use each card's TDS link for verified specifications before specifying on any project.
System Description
For dormant or movement cracks routed and sealed. Joint width to depth ratio 2:1. Bond breaker tape at base.
Technical Properties
- Excellent movement accommodation — typically rated ±25–35% of joint width
- Paintable when cured — can be colour-matched to adjacent surfaces
Limitations
- Requires compatible primer on porous or chemically reactive substrates
- Cure rate is temperature-dependent — very slow below 10°C
PROCUREMENT SOURCES
System Description
For dormant or movement cracks routed and sealed. Joint width to depth ratio 2:1. Bond breaker tape at base.
Technical Properties
- Excellent movement accommodation — typically rated ±25–35% of joint width
- Paintable when cured — can be colour-matched to adjacent surfaces
Limitations
- Requires compatible primer on porous or chemically reactive substrates
- Cure rate is temperature-dependent — very slow below 10°C
PROCUREMENT SOURCES
Fosroc Thioflex 600 (polysulfide) / Nitoseal MS600 (MS polymer)
flexible joint sealants, 600 mL cartridge
System Description
For dormant or movement cracks routed and sealed. Joint width to depth ratio 2:1. Bond breaker tape at base.
Technical Properties
- Excellent movement accommodation — typically rated ±25–35% of joint width
- Paintable when cured — can be colour-matched to adjacent surfaces
Limitations
- Requires compatible primer on porous or chemically reactive substrates
- Cure rate is temperature-dependent — very slow below 10°C
PROCUREMENT SOURCES
System Description
For dormant or movement cracks routed and sealed. Joint width to depth ratio 2:1. Bond breaker tape at base.
Technical Properties
- Excellent movement accommodation — typically rated ±25–35% of joint width
- Paintable when cured — can be colour-matched to adjacent surfaces
Limitations
- Requires compatible primer on porous or chemically reactive substrates
- Cure rate is temperature-dependent — very slow below 10°C
PROCUREMENT SOURCES
System Description
For dormant or movement cracks routed and sealed. Joint width to depth ratio 2:1. Bond breaker tape at base.
Technical Properties
- Excellent movement accommodation — typically rated ±25–35% of joint width
- Paintable when cured — can be colour-matched to adjacent surfaces
Limitations
- Requires compatible primer on porous or chemically reactive substrates
- Cure rate is temperature-dependent — very slow below 10°C
PROCUREMENT SOURCES
Brand Equivalents
Side-by-side view of equivalent products across all major brands.
| Material | Ardex | Sika | Fosroc | Tremco / Other | Parchem / Mapei |
|---|---|---|---|---|---|
| Polyurethane sealant (flexible joint) | Ardex RA 040 | Sika Sikaflex-11FC / Sikaflex Pro-3 WF | Fosroc Thioflex 600 (polysulfide) / Nitoseal MS600 (MS polymer) | Tremco Dymonic 100 | Parchem Pro-Sealant PU600 |
Disclaimer
Information is general only. Product selection must be confirmed against project requirements, substrate condition, exposure class, manufacturer technical data sheets, NCC requirements, Australian Standards (including AS 3600), and consultant or structural engineer specifications. Do not rely on this reference as a substitute for professional engineering advice.
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