What is Selleys Pro Trade Joint Sealant FC, and where should you use it?
Pro Trade Joint Sealant FC is a fast curing polyurethane adhesive and sealant with high flexibility and excellent adhesion. It is waterproof, suitable for indoor and outdoor applications, and paintable after it has cured. It works as both a high strength multipurpose adhesive and a flexible joint sealant, for internal and external vertical and horizontal applications.
The characteristic that sets it apart from a silicone is that it is rated for trafficable areas — paths, stairs and pavements. Very few flexible sealants will take foot traffic. If your joint is walked on, that is the reason to choose a polyurethane like this one over a silicone.
Technical specification
| Property | Typical result |
|---|---|
| Technology | Polyurethane |
| Colour | White, grey and black |
| Density | 1.08 ±0.03 g/ml |
| Application temperature | 5°C to 40°C |
| Tack-free time (23°C, 50% R.H.) | 40 ±10 minutes |
| Cure rate (23°C, 50% R.H.) | Min. 3mm per 24 hours |
| Sagging (EN ISO 7390) | 0mm |
| Tensile strength (ISO 37) | 2.0–2.5 N/mm² |
| Elongation at break (ISO 37) | 400% |
| Shore A hardness (ISO 868) | 40 ±5 |
| Modulus at 100% elongation (ISO 8339) | 0.35–0.40 N/mm² |
| Movement capability | ±25% |
| Service temperature | −40°C to +70°C |
| Packaging | 600ml foil sausage and 310ml cartridge, each in white, grey and black |
These are indicative data only, not intended for the preparation of specifications.
What the key numbers mean in practice
Sagging of 0mm to EN ISO 7390 is a specific, tested claim, not a description. It means the bead does not slump out of a vertical or overhead joint while it cures. That is what makes the product usable on a facade or a parapet where a slumping sealant would leave the top of the joint starved and the bottom overfilled.
The cure rate is a minimum of 3mm per 24 hours. Like all moisture-cured polyurethanes it cures inward from the surface, so a joint's depth sets the timeline: a 10mm-deep joint is a multi-day cure, not an overnight one. That matters most on trafficable joints — do not open a path or a set of stairs to traffic on the strength of the tack-free time.
Tack-free at 40 ±10 minutes is your tooling window. All smoothing must be done before the surface goes tack-free, so work in lengths you can finish. In warm or humid conditions the window is at the shorter end of that range.
±25% movement capability with 400% elongation at break and a Shore A of 40 ±5 describes a firm but very stretchy sealant. The relatively high hardness is what lets it carry traffic; the elongation is what lets it absorb movement. The modulus at 100% elongation of 0.35–0.40 N/mm² is the load it puts back onto the joint faces as it stretches — low enough that it will not tear render or a weak masonry face.
Joint design — get this right first
The dimensions matter more than the application technique, and the manufacturer is specific:
- The optimum width to depth ratio for joint sealing is 2:1.
- Minimum joint width and depth is 10mm.
- For joint widths up to 12mm, use a width to depth ratio of 1:1.
- For joint widths greater than 12mm, use a width to depth ratio of 2:1.
Three notes follow from that. Wider joints can accommodate more total movement than narrow joints — if you have a choice at design stage, a wider joint buys you more absolute movement at the same percentage capability. Always install a suitable diameter backing rod (polyethylene or polyurethane foam rod) in joints, to control sealant depth and ensure free movement of the sealant. And critically: the sealant must adhere to the sides of the joint only and NOT to the back, so that it is free to stretch. Three-surface adhesion is the most common reason a correctly specified sealant still tears.
Coverage
| Joint width | Joint depth | Joint length per 600ml |
|---|---|---|
| 15mm | 8mm | 5 m |
| 20mm | 10mm | 3 m |
| 25mm | 12mm | 2 m |
| 30mm | 15mm | 1.3 m |
| 35mm | 15mm | 1.1 m |
Where to use it
As a sealant and adhesive for common building materials:
- Sealing gaps and adhering most facade and cladding panels to various building materials
- Weatherproofing joints between brickwork, masonry, concrete, cladding, wood or metal frames
- External joints in walls and around window or door frames
- Sealing construction and expansion joints
- Sealing floor and concrete joints
- Trafficable areas including paths, stairs and pavements
- Joints in bridge and balcony parapets
- Retaining walls
- Roofing
- Acoustic rated walls
- As an adhesive for indoor and outdoor bonding of window sills, thresholds, stair steps, skirting boards, base boards, crash protection boards, covering boards and prefabricated elements
It has excellent adhesion on common building materials such as concrete, masonry, brick, ceramic tile, metals, soft wood, hardwood and some plastics. It also cures bubble free with no shrinkage during curing, and has excellent resistance to ageing and weathering. For a low-modulus alternative in the same range, see Pro Trade Joint Sealant LM.
How to apply it
Surfaces must be clean, dry and free from oil, grease, release agents, dust and loose material. The product generally has good adhesion properties without priming to the common building materials indicated, but a pre-test to ensure suitable adhesion is recommended.
The directions below should only be used as a guide — the installer should apply all Australian Standards, BCA/NZBC requirements, and best practices when installing.
As a sealant
- Cut the end of the sausage and insert it into a Selleys sausage gun. For cartridges, completely pierce the metal foil seal inside the cartridge nipple, trim the nozzle and screw it onto the cartridge, then insert into a caulking gun.
- Install a backing rod to the correct depth and apply masking tape as required.
- Extrude the sealant into the joint so that it is in full contact with the sides of the joint. Avoid overlapping the sealant, which traps air.
- Smooth the sealant with a spatula, forcing it into the joint for better contact with the sides. Tooling is not just cosmetic — it is what presses the sealant against the joint faces.
- Paint with water-based paints after curing. If solvent-based paints are used, prime first with a water-based primer.
As an adhesive
- Apply a bead or small blobs of product onto the surface of the substrate.
- Assemble the parts together and clamp firmly to hold them in place until the product cures.
- Remove excess adhesive immediately. Cured product can only be removed mechanically.
- Allow 24 hours for the initial bond, depending on temperature and humidity. Bond strength increases over a few days, so do not load the joint fully at 24 hours.
Limitations — where it should NOT be used
- Not recommended for continuous submersion or below water-line use.
- Will not adhere to polyethylene or polypropylene. Test adhesion on other plastics before application.
- Do not apply on frozen or wet surfaces, or through standing water.
- Paint restrictions: suitable for most water-based paints. For oil-based paints, undercoat with a water-based primer. Testing is recommended if paint is applied more than 5 days after sealant application.
That last point is easy to miss and worth planning around. A polyurethane surface continues to change as it cures, so a paint that adheres well at day two may not at day ten. If your programme puts painting well after sealing, test first on a sample bead of the same age.
Clean up and storage
Tools and uncured product may be cleaned using mineral turps. Cured product can only be removed mechanically.
Shelf life is 15 months if stored in its original package, away from direct sunlight and moisture, between 10°C and 25°C. A site store that regularly exceeds 25°C will shorten that.
Hazard classification
Selleys Pro Trade Joint Sealant FC is not classified as hazardous under the criteria of Safe Work Australia GHS 7. No signal word is assigned and no hazard statements apply, because the product does not meet the threshold for any GHS hazard class.
It is not classified as Dangerous Goods for any transport mode: not under the Australian Code for the Transport of Dangerous Goods by Road & Rail or New Zealand NZS5433 on land, not under the IMDG Code by sea, and not under the IATA Dangerous Goods Regulations by air.
For a fast-curing one-part polyurethane that is a better result than the chemistry would lead you to expect. Polyurethane sealants are the family in which free isocyanate monomer normally produces a sensitisation classification, and this one has none at all. That is what the classification says; the safety data sheet does not set out the composition in the material available here, so nothing is claimed about why.
Not hazardous is not the same as requires no care, and two ordinary precautions are worth keeping. Ventilate the work area — the safety data sheet notes that no occupational exposure limits are assigned for this material and that general ventilation is adequate under normal use, which is a statement about normal use rather than about a sealed plant room or an unventilated basement. And protect your eyes: if the product gets in them, wash out immediately with water and seek medical advice as a precaution. Wash your hands before eating, drinking or smoking, and store the product in a cool, dry, well-ventilated place away from direct sunlight and away from heat and ignition sources.
Common questions about Pro Trade Joint Sealant FC
Can I use it on a path or stairs?
Yes. Trafficable areas including paths, stairs and pavements are among its listed uses.
How long before it is tack-free?
40 ±10 minutes at 23°C and 50% relative humidity. Do all tooling before that.
How fast does it cure through?
A minimum of 3mm per 24 hours, so depth sets the timeline.
How much movement will it take?
±25%.
Can I paint it?
Yes, after curing, with most water-based paints. For oil-based paints, undercoat with a water-based primer. Test first if you are painting more than 5 days after application.
Do I need a primer for adhesion?
It generally has good adhesion without priming to the common building materials listed, but a pre-test is recommended.
Do I need a backing rod?
Yes — always install a suitable diameter polyethylene or polyurethane foam backing rod to control depth and let the sealant move freely. The sealant must adhere to the sides of the joint only, not the back.
What joint dimensions should I use?
Minimum 10mm width and depth. Use 1:1 width to depth up to 12mm wide, and 2:1 above 12mm.
Will it sag in a vertical joint?
No — sagging is 0mm to EN ISO 7390.
Will it stick to plastic?
Not to polyethylene or polypropylene. Test other plastics before application.
Can I apply it in the rain, or on a damp surface?
No. Do not apply on frozen or wet surfaces, or through standing water.
Can it be submerged?
No — not recommended for continuous submersion or below water-line use.
How long before an adhesive joint takes load?
Initial bond is achieved in 24 hours depending on temperature and humidity, and bond strength increases over a few days.
What sizes and colours are available?
600ml foil sausages and 310ml cartridges, in white, grey and black.
How do I clean up?
Mineral turps for tools and uncured product. Cured product can only be removed mechanically.
What is Pro Trade Joint Sealant FC and what technology does it use?
Pro Trade Joint Sealant FC is a Selleys fast curing polyurethane adhesive and sealant with high flexibility and excellent adhesion, based on polyurethane adhesive & sealant technology.
What colours and packaging sizes are available for Pro Trade Joint Sealant FC?
Pro Trade Joint Sealant FC is available in White, Grey, and Black, packaged as a 310mL cartridge or a 600mL foil sausage.
What is the tack-free time and cure rate of Pro Trade Joint Sealant FC?
Pro Trade Joint Sealant FC has a tack-free time of approximately 40 ±10 minutes at 23°C/50% RH, and a cure rate of at least 3mm per 24 hours.
What tensile strength and elongation does Pro Trade Joint Sealant FC achieve?
Pro Trade Joint Sealant FC has a tensile strength of approximately 2.0–2.5 N/mm² and an elongation at break of ≥400%.
What is the service and application temperature range for Pro Trade Joint Sealant FC?
Pro Trade Joint Sealant FC can be applied between 5°C and 40°C, and once cured it withstands service temperatures from –40°C to +70°C.
What are the limitations of Pro Trade Joint Sealant FC?
Pro Trade Joint Sealant FC is not suitable for continuous submersion or below-water-line use, will not adhere properly to PE or PP plastics (other plastics should be tested before use), and should not be applied on frozen or wet surfaces.
How should surfaces be prepared and the sealant applied according to the directions for use?
Surfaces should be cleaned thoroughly to remove dirt, oil, release agents, and loose material; the nozzle is cut and the cartridge or sausage loaded into a gun, piercing the seal if needed; a backing rod can be inserted if required and edges masked for a neat finish; the sealant is then extruded ensuring full side contact while avoiding trapped air, and the bead is tooled for a smooth finish.
Can Pro Trade Joint Sealant FC be painted, and how is uncured or cured sealant cleaned up?
Once cured, Pro Trade Joint Sealant FC can be painted with water-based paints directly, or with oil-based paint if a primer is used first; uncured sealant can be cleaned with mineral turps, while cured product must be removed mechanically.
What is the Shore A hardness and sag rating of Pro Trade Joint Sealant FC?
Pro Trade Joint Sealant FC has a Shore A hardness of approximately 40 ±5 and a sag rating of 0mm according to EN ISO 7390.
What density does Pro Trade Joint Sealant FC have?
Pro Trade Joint Sealant FC has a density of 1.08 ±0.03 g/mL.