The Cromar Trowel Mastic is a bituminous mastic that is used for filling joints, cracks and splits in roofing and building materials. This mastic can be used on a range of roofing materials, including roofing felt, asphalt and concrete to provide a durable, water resistant seal.

Key Features

• Can be used on asbestos cement and metallic drainpipes and gutters
• Best used for maintaining and repairing roofing
• Designed for filling cracks and joints in roofing
• Suitable for use on asphalt, felt and concrete
• Offers incredible water resistance

Technical Information

• Coverage: 2L/m² at a 2mm thickness
• VOC content: max. 180g/l
• Colour: Black
• Volume: 5L

Application Instructions

1. Ensure that the surface is clean, dry and free from oil, grease, dirt and organic growth
2. Bolt heads on roof sheets should be wired brushed to remove rust
3. Porous surfaces should be primed and left to dry thoroughly before applying the mastic
4. Tools may need to be lubricated with white spirit or paraffin for an easier application
5. Apply the mastic by trowel or putty knife, forcing material into cracks and joints and smoothing it out on either side
6. Cracks or joints of more than 3mm should be reinforced with glass fibre scrim and covered with a second application of mastic