Technical Data Sheet
| Document | RY-TDS-1101 |
|---|---|
| Revision | Rev. 1.0 |
| Issue date | July 2026 |
| Status | Issued |
Rayson SealForce · Polyurea waterproofing membranes
Rayson SealForce RC40 is a two-component, cold-applied aliphatic polyurea waterproofing membrane for exposed roofs — roller-, brush- or spray-applied, UV-stable and walkable, with certified cool-roof reflectance.
SealForce RC40 is Rayson's cold-applied roof waterproofing membrane: a two-component, aliphatic (polyaspartic) polyurea that brushes, rolls or sprays onto a primed roof and cures to a seamless elastic film. Because the polymer is fully aliphatic, it holds its colour and gloss under direct sun where ordinary aromatic membranes darken.
Standalone coating.
Figure 1 — Typical system build-up (top to bottom). Layer thicknesses are system-dependent; confirm the specification for your project.
| Surface preparation | Substrate must be stable, clean, dry and free of dust, oil, grease, loose material and rising moisture. Remove poorly adhering coatings and treat irregularities so the surface is flat, continuous and correctly falled. Prime with the Rayson primer matched to the roof material before waterproofing. |
|---|---|
| Mixing / dilution | Two parts mixed 13:8 (A:B) by weight; stir Part A ~1 minute, then combine and low-speed mix ~3 minutes until homogeneous; apply undiluted in at least two layers |
| Application method | Roller, Brush, Airless spray |
| Coverage | 1–1.2 kg/m² total over two layers on cementitious surfaces |
| Application conditions | Substrate moisture below 4%; relative humidity below 85%; ambient and substrate temperature +5 °C to +35 °C; substrate at least 3 °C above dew point. |
| Drying & curing | Touch/recoat ~18 h at 23 °C; resists early rain after 3 h; full hardening ~7 days |
| Recoat interval | Recoat about 18 hours after the previous layer at 23 °C; times lengthen in cool, humid weather and shorten in heat. |
| Film / thickness | Built in at least two layers; keep each unreinforced layer below 1 kg/m² to avoid solvent entrapment. |
| Pack sizes | Sets (A+B) of 21 kg and 5.25 kg |
| Storage | Store sealed and upright, protected from frost, humidity and sunlight. Component A keeps ~2 years, Component B ~1 year. |
| Shelf life | Component A approximately 2 years; Component B approximately 1 year, in sealed original packaging. |
Figure 2 — Application workflow. Each stage is a hold point: confirm the previous stage is complete and within specification before proceeding.
Exposed roof waterproofing (cementitious)
Two-component product. Wear gloves, eye protection and suitable respiratory protection where ventilation is limited. Avoid skin and eye contact. Keep out of reach of children. Consult the Safety Data Sheet (in preparation) before use.