Asbestoseal 20 – Asbestos Roof Coating System - Liquid silicone

Thoroughly clean surfaces and allow to dry.

Guidance for specification option:

In all cases, the asbestos cement substrate will require cleaning. Jet wash lances should not be used, as they can destroy the asbestos cement substrate.

One of the following methods should be employed:

• Closed Box Pressure wash (HSE Approved Method).
• Steam cleaning using DOFF 150°C steam (Not HSE Approved).

All waste must be treated as being contaminated with asbestos and must be double bagged and then disposed of using a licensed disposal facility, with consignment note retained for the health and safety file. Waste water must be filtered to 5 μm to ensure that no waste water enters the mains drainage system.

Additional reference: see HSE guidance note a12, “Cleaning weathered asbestos cement (AC) roofing and cladding” http://www.hse.gov.uk/pubns/guidance/a12.pdf.

All surfaces must be clean and dry prior to application. Please note that when using airless spray, an initial mist coat of ASBESTOSEAL 20, or use of Liquasil Asbestos Cement Stabilising Solution is strongly recommended in order to achieve a uniform finish on porous substrates. 

Consult manufacturer's literature for further details on spray application guidelines.

SWT Corrosion Primer.

Guidance for specification option:

Two-part epoxy comprising the primer (part A) and the hardener (part B). Rust and wet tolerant for application to all metal fixings such as hook bolts to prevent rust from breaking through the coating.

Technical characteristics:

• Colour: Grey.
• Solids content: 100%.
• Coverage: Up to 6 m²/kg.
• Drying time: 6–24 hours.
• Weight: 1 kg/L.
• Flash point: >100°C.
• VOC content: 0 g.
• Finish: Semi-gloss.
• Application temperature: -20°C to 40°C.

Non-Sag Sealer.

Guidance for specification option:

A specially formulated silicone that is brush applied to all primed fixings to re-seal failed rubber seals, and for instantly sealing small holes and cracks in roof sheets. Roofs with a shallow pitch will especially benefit from overlapping joints being sealed.

ASBESTOSEAL 20.

Guidance for specification option:

The coating that is applied to the entire roof to form a complete membrane that will protect the asbestos cement roof sheets from further deterioration. If aesthetics are important, please specify two coats pf Asbestoseal 20.

Technical characteristics:

• Composition: Viscous liquid.
• Odour: Mild/ faint.
• Melting point: <-60°C.
• Initial boiling point and range: 185–255°C (at 1013 hPa).
• Flash point (closed cup): 67°C.
• Vapour pressure: 0.035 kPa (at 20°C).
• Relative density: ~1 (at 20°C).
• Viscosity: ≤50 P (at 20°C).
• Solids content: 85%.
• Recommended film thickness: 300–350 μm.
• Coverage: Up to 2.5–3.2 m²/L (at 300 μm: 2.6 m²/L; at 250 μm: 3.2 m²/L).
• Drying time: Should be rain free for 2–4 hours. Thoroughly dry after 8 hours.
• Weight: 1 kg/L.
• VOC content: 45 g/L.
• Application temperature: -5°C to 60°C.

ASBESTOSEAL SF.

Guidance for specification option:

Can be specified in cases where solvents cannot be used.

Asbestoseal Solvent Free (SF) can be applied by brush and roller only.