For sealing construction joints, building claddings, curtain walls, and perimeter joints around door and window frames, Pasco Hypersil 911 provides a highly flexible, weatherproofing barrier. This 100% silicone sealant is formulated to absorb continuous movement and resist harsh UV exposure without degrading, cracking, or losing adhesion over time.
Hypersil 911 uses a neutral-curing mechanism that does not release corrosive acids during curing, making it safe for use on steel, aluminium, stainless steel, and concrete without damaging the substrate. It adheres reliably to non-porous surfaces like glass and ceramic tiles, as well as porous masonry. The non-slumping formulation ensures the bead stays in place during vertical installation in wide construction joints or window claddings. During application, the curing process releases Methyl Ethyl Ketoxime (MEKO), requiring ventilation until the rubber is fully formed.
Suitable for general purpose glazing, weatherproofing, and specialist trade sealing on:
Correct joint geometry is necessary to prevent splitting. Use an open-cell polyethylene backing rod to control sealant depth and ensure two-sided adhesion. Choose a closed-cell backing rod sized to allow 25% compression when inserted. Joint sizing must follow these limits:
Ensure all substrates are clean, dry, and sound. Clean glass and metal surfaces with methylated spirits and wipe dry with a clean cloth before applying the sealant. Tool the joint dry immediately after application to ensure complete wet-out of both joint faces.
Yes, Hypersil 911 is a neutral cure silicone sealant that will not corrode metals or stain sensitive natural and reconstituted stone. This prevents etching and discolouration often caused by acid-cure silicones on such substrates. Always test a small area for compatibility before full application.
No, Hypersil 911 is not paintable. Silicone sealants, especially 100% silicones, generally do not accept paint well. If you require a paintable sealant, a different product chemistry is needed to prevent adhesion issues and peeling of the paint layer.
Hypersil 911 develops a skin in 8-10 minutes at 20°C and 50% relative humidity. For a 10mm deep bead, full cure typically takes 5-7 days at 25°C. Allow sufficient time before exposing the joint to full stress or further work.
No, Hypersil 911 is not designed or tested for structural glazing applications. Structural glazing requires specific sealants engineered to bear significant loads and must comply with relevant Australian standards for such use. Using this product for structural glazing will result in failure.
| Application | Key benefit | Primary trades |
|---|---|---|
| General glazing perimeter seals | Forms a durable, waterproof seal with ±25% movement capability, resisting UV degradation for long-term performance. | Glaziers, Commercial Builders, Shopfitters |
| Curtain walls and building claddings | Neutral cure formulation prevents corrosion on aluminium, steel, and painted surfaces, avoiding staining and premature system failure. | Facade Installers, Commercial Builders |
| Construction joint sealing | High flexibility and excellent adhesion across various materials ensure joints tolerate movement and maintain weatherproofing. | Builders, Concrete Finishers, Masons |
| Perimeter sealing of door and window frames | UV stability and low odour make it suitable for exterior and interior applications, ensuring a lasting, flexible seal against weather. | Carpenters, Window Installers, Builders |
| Sealing natural and reconstituted stone | Non-staining, neutral cure chemistry protects sensitive stone surfaces from discolouration while providing a flexible seal. | Masons, Tilers, Stonemasons |
Signal Word: Danger
Wear safety shoes, overalls, gloves (nitrile rubber recommended), and chemical goggles. A suitable respirator should be worn if avoiding breathing dust or fume is not possible through ventilation. Ensure contaminated work clothing is not taken out of the workplace and is washed before reuse.
Use only in well-ventilated areas to avoid inhalation of vapours. This product emits Methyl Ethyl Ketoxime (MEKO) while curing, which can cause respiratory system irritation.
Store locked up in a cool, dry, well-ventilated place, out of direct sunlight and away from foodstuffs and incompatible materials. Keep containers closed when not in use. Shelf life is 12 months minimum when stored below 28°C. Dispose of contents and container in accordance with local and national regulations.
Proper substrate preparation is critical for the long-term performance of any sealant. Ensure all surfaces are sound and free from contaminants.
Surface prep: All surfaces must be clean, dry, sound, and free from dust, oil, rust, old sealant, or other contamination. Clean glass and metal surfaces with methylated spirits. Wipe the solvent from the surface immediately with a clean, dry cloth to remove residues.
Primer: Not required. Hypersil 911 offers superior adhesion to these materials without a primer when properly prepared.
Surface prep: Ensure surfaces are clean, dry, and sound. Remove all dust, loose particles, oil, and other contaminants. For stone, test a small, inconspicuous area for compatibility (adhesion/staining) prior to full application.
Primer: Not required for most applications. If adhesion is questionable or porosity is high, conduct a small test for bond strength before proceeding.
Surface prep: Ensure surfaces are clean, dry, and free from contamination. Test a small area for compatibility (adhesion/staining) prior to application. Hypersil 911 is not suitable for polycarbonate plastic sheeting or certain rubber products where plasticiser bleeding may occur.
Primer: Not required in most cases. Compatibility testing is essential due to the wide variety of plastic types.
| Property | Value |
|---|---|
| Elongation | 400% |
| Hardness (Shore A) | 30 |
| Joint Movement Capability | ± 25% |
| Sag/Slump | Non slump (0.1") |
| Tensile Strength | 20 KHF/CM2 (2.0 MPa) |
| Cure Method | Neutral |
| Specific Gravity | 1.04 |
| Skin Time | 8-10 min @ 20°C & 50% RH |
| Cure Time (10mm depth) | 5-7 Days @ 25°C |
| Operating Temperature Range | -62°C to +170°C |
| VOC Content | 31 gr/L |
| Shelf Life | 12 months minimum below 28°C |
Here are some common examples on where Pasco Hypersil 911 Silicone Sealant used by our customers.
