

Flash Harry Bitumen Mastic Trowelable Waterproofing Sealer 1 Litre
49 in stock
Fast, tracked courier across South Africa
Unused, in original packaging
Flash Harry Bitumen Mastic Trowelable Waterproofing Sealer 1 Litre is a heavy-duty, trowel-applied compound for sealing roofing defects and repairs. With a built-in membrane, this 1 litre size is a practical choice for medium roof repairs and waterproofing around fixings, laps and gutters.
Key Features
- Trowel-applied heavy-duty compound for roofing repairs.
- Built-in membrane that removes the need for a separate membrane.
- Versatile sealing of screw bolts, nail holes, sheeting laps, valleys and gutters.
- Solvent-based and effective even when rain is imminent.
- Overcoatable with Alu-Coat Silver in UV-exposed areas.
- Easy cleanup with thinners, solvent or petrol.
- 1 litre size suited to medium patch and repair jobs.
Specifications
- Size: 1 Litre
- Type: Trowelable bitumen mastic waterproofing sealer
- Base: Solvent-based
- Membrane: Built-in
- SKU: A10382
- Barcode: 6009691023927
Typical Uses & Applications
- Sealing roof screw bolts and nail holes on corrugated and IBR roofs.
- Patching sheeting laps where sheets overlap.
- Repairing valleys and gutters prone to leaks.
- Sealing around downpipes and roof penetrations.
- Fixing cracked tiles and small roof defects.
- Urgent repairs before rain where solvent-based cure helps.
Usage Tip
Clean the area of dust and loose material, then trowel the mastic firmly over the defect, working it into the joint. In UV-exposed areas, overcoat with Alu-Coat Silver for added protection, and clean tools with thinners or solvent. Take fire precautions, as it is flammable when wet.
A dependable, membrane-backed seal for keeping roofs watertight.
About FLASH HARRY
Flash Harry offers practical building and waterproofing products aimed at fast, effective repairs for contractors and homeowners alike, formulated for real-world roofing and sealing jobs.
What's in the box:
1 x Flash Harry Bitumen Mastic Trowelable Waterproofing Sealer 1 Litre
| Weight | 1.12 kg |
| SKU | A10382 |
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