Description
Roberts R280 HT is a fibre-reinforced, high-temperature hard-set adhesive built specifically for the demanding conditions of bay windows, glass shop fronts and other areas exposed to direct sunlight, where standard vinyl adhesives can soften or fail under sustained heat. Its excellent plasticiser migration resistance and non-staining properties are what let it hold up in these high-temperature, high-shear environments without degrading over time.
Being suitable for underfloor heating installations as well extends its use beyond just sun-exposed areas into any application demanding real temperature resistance. Its short open time — generally 5 minutes at 20°C — reflects its fast, hard-setting chemistry, meaning installers need to work in smaller sections rather than spreading a large area before laying flooring.
Its fibre reinforcement and high shear resistance give R280 HT genuine structural performance in demanding sun-exposed locations like bay windows and glass shop fronts, where a standard vinyl adhesive can soften or creep under sustained heat load. Suitability for underfloor heating installations further extends where it can be specified, though direct sunlight during the actual installation process should still be avoided even though the cured, set adhesive is rated to handle ongoing sun exposure once fully cured.
Technical Specifications
| Appearance | Creamy white paste |
|---|---|
| Open time | 0-10 minutes at 20°C |
| Application temperature | 10°C to 30°C |
| Moisture tolerance | Up to 85% RH (ASTM F2170) |
| pH tolerance | Up to 10.0 |
| Set to traffic | 24 hours |
| Coverage (V1 1.6mm) | Approx. 5m² per litre |
| Coverage (V2 2.4mm) | Up to 3m² per litre |
| Packaging | 15 litre containers |
Where to Use
- PVC vinyl plank and tile flooring
- Vinyl composite tiles
- Bay windows, glass shop fronts and other sunlight-exposed areas
- Underfloor heating installations (not suitable for rubber floorcoverings)
How to Apply
- Prepare the substrate — dry, smooth, sound, clean and free of laitance on concrete.
- Test moisture — confirm concrete moisture per AS1884-2021 and ASTM F2170.
- Spread within the open time — apply only as much as can be covered within the short 0-10 minute open time.
- Lay the flooring — lower into the wet film and roll in both directions.
- Shade sun-exposed areas during installation — keep the work area shaded during application per relevant standards.
Important Notes
- Not suitable for rubber floorcoverings.
- Do not apply in direct sunlight during installation, even though the cured adhesive is rated for sun exposure once set.
- For interior use only; do not apply below 10°C.
