Sika Black Jack Strong Self Adhesive Flashing Tape – Natural Lead-Look Finish – 100mm x 10m
Product description
What it is and what it solves
Sika Black Jack Strong Self Adhesive Flashing Tape is a lead-free flashing solution that aims to replace traditional lead flashing in a cost-conscious, theft-reducing way. It’s designed for a straightforward, hand-press application, eliminating the need for separate adhesives in most situations.
How it works

The tape is self-adhesive, forming a seal simply by pressing it into place. Its flexible nature makes it suitable for bonding to roof ridges and various insulating materials, with the aim of delivering a durable waterproof layer.
Pros and what stands out


On the page, the product is pitched as economical and practical for multiple roofing tasks. It could suit DIYers or professionals looking for a lead-free alternative that can still be shaped and positioned by hand. The natural lead-look finish may help visually integrate with traditional roofing aesthetics where lead flashing is present.

Potential limitations or things to consider
It is described as a cost-effective option, but as with any flashing tape, it may not be a perfect substitute in every scenario. The claims focus on ease of use and versatility, yet concrete performance data, long-term durability benchmarks, and compatibility with all roof types aren’t provided here. If you prioritise ultra-high durability or extreme climate performance, you may want to compare with more niche products. Also, not all widths come in the 3-metre length, so you’ll need to check availability for your project scale.
Who it’s for

This tape seems suited to homeowners and installers seeking a lead-free alternative that is quick to apply, with the flexibility to cover gaps and joints on roofs, gutters and concrete repairs.


Who it isn’t ideal for
If your project demands the highest-end longevity under severe weather conditions, or you require a product with specific technical certifications, this option might not be the ultimate choice.

Practical use case
For a straightforward roof repair on a low-slope section, you can cut a piece, peel back the backing, and press the tape along the joint to form a seal. The 100mm width is a common size for broader flashing tasks, while longer runs reduce the frequency of reapplication.
Before you buy: quick checks



- Confirm the required width and length for your job, noting that not all widths come in 3-metre lengths.
- Ensure surface is clean, dry and free of loose material to maximise adhesion.
- Consider the aesthetic: the natural lead-look finish aims to blend with traditional profiles, but it remains a tape product rather than solid flashing.
In the context of alternatives
If you’re weighing approaches, you could opt for traditional lead flashing or other single-pace flashing tapes. This option prioritises ease of use and value for money, with a practical approach to everyday roofing tasks rather than aiming for premium performance in all conditions.

Final decision section
Is it worth it?
Worth considering if you’re after a lead-free, self-adhesive flashing solution that’s quick to apply and budget-conscious for general flashing and minor repairs. It may not be the best fit if you need top-tier long-term durability in extreme environments. A practical choice for typical residential roof repairs where ease of use and cost matter.
FAQ
- How is the tape applied? It’s self-adhesive and pressed into place by hand.
- What widths are available? The product line includes 75mm, 100mm, 150mm, 225mm, 300mm and 450mm options, lengths include 3m and 10m, with not all widths offered in 3m.
- Can it be used for concrete cracks? Yes, it’s listed as suitable for repairs in concrete,
- Is it lead-based? No, it’s lead-free by design, which also helps reduce theft risk in some contexts.
Products with discounts that might interest you
- ZISMA 50 Pcs Heavy Duty Double Sided Adhesive Pads – 50x30mm Foam Tape for No-Drill Mounting
- LLPT Duct Tape 50MM x 9M Green | Premium Colour Fabric Gaffer Tape
- ScotchBlue Multi-Surface Premium Masking Tape, 24 mm x 41 m (Pack of 3) – Indoor & Outdoor
- Emitever 6311 Heavy-Duty Double Sided Tape (10mm x 3m) for strong, residue-free mounting
- Amazon Basics Heavy Duty Duct Tape 4-pack
- ScotchBlue Multi-Surface Premium Masking Tape (36 mm x 41 m) – 4 Rolls
- Emitever 68211 double sided mounting tape 8.2m
- 3M 5925 Double Sided Mounting Tape (50mm x 4.7m) Black, 0.6mm Heavy Duty Foam
- Emitever Picture Hanging Strips Heavy Duty M-20
- Magnetic Strips with Adhesive Backing 10 pack 🧲
- AmazonBasics Painter's Tape, 2.3 cm x 55 m (Pack of 4 Rolls) – Blue
- 3M Scotch-Fix Double-Sided Exterior Tape 19mm
- Storystore Self-Adhesive Foam Insulation Tape (25mm x 20mm x 5m) for Draught, Sound & Weather Sealing
- Hook and loop tape 5 m for strong fixing
- Easyojoy Picture Hanging Strips (72 strips / 36 pairs) – heavy-duty removable double-sided frame tape for damage-free mounting
- DIY Doctor A+B Magnetic Tape (2m + 2m) – Self-adhesive cut-to-fit magnetic strips
- Summerbrite Heavy Duty Picture Hanging Strips (XL) – 25 Pairs (50 Strips)

