BLACK JACK BITUMEN MASTIC is ready for use and should not be thinned. Apply by steel trowel or putty knife.
CRACKS AND HOLES
- Force the compound into the crack, but finish with a 25mm band at a 3mm thickness running the length of the crack. For large cracks and holes, apply the compound over the area to be treated and embed a closely woven glass fibre membrane into the compound to overlap the crack or hole by 50mm. Allow to dry and then apply a second coat, fully covering the reinforcing membrane.
CORRUGATED IRON/FIBRE CEMENT SHEETING
- Tighten loose hook bolts and trowel around with mastic. Remove loose screws, re-bed screws and washers in BLACK JACK BITUMEN MASTIC and tighten. Top seal in further mastic and trowel to a smooth finish. If the sheet is cracked, clean and prime with BLACK JACK Bitumen/FLASHING Primer and apply a bandage strip of glass fibre embedded in the mastic. When dry, overcoat with BLACK JACK BITUMEN /FLASHING PRIMER followed by BLACK JACK BITUMEN PAINT. Use the same technique for sealing side and end laps in corrugated sheeting.
- Point up butt edges of ridge tiles, fillets and slates with BLACK JACK BITUMEN MASTIC.
LEAD AND ZINC
- Trowel over cracks and pinholes, where necessary, reinforcing with a woven glass membrane, fully embedded and covered.
- Re-adhere loose felt using BLACK JACK ROOF FELT ADHESIVE. Apply BLACK JACK BITUMEN MASTIC and overcoat with BLACK JACK ALL WEATHER ROOF COATING. Note: felt must be completely dry before applying the mastic.
- Tools may be cleaned by using white spirit. Spillage’s should be wiped off surfaces before the primer has set.