Membrane Seam and Junction Tape Order calculator.
Order rolls from measured seam runs, specified end allowances and separate junction patches, with explicit joining rules.
Your inputs
Use measurements from your plan and properties from your chosen product. Any prefilled values are illustrative.
A clear estimate starts here.
Enter your dimensions and product details to see the quantity and purchase breakdown.
Formula and assumptions
How this calculation works.
Order rolls from measured seam runs, specified end allowances and separate junction patches, with explicit joining rules. Tape length = Σ(run + 2 × end allowance) × count + patch count × patch length. Pool only if joins are permitted.
A worked example
Illustrative inputs only. Product properties and design dimensions are not recommendations for your project.
- Selected tape roll length
- 10 m
- Specified extra length at each seam end
- 0.1 m
- Separate junction patches
- 2
- Specified length per junction patch
- 0.5 m
- Your permitted joining plan
- Continuous pieces required
- Measured run length
- 6 m
- Identical runs
- 2
Seam tape rolls: 2 rolls
Continuous-piece packing uses decreasing-length first fit. It is feasible for the stated pieces but is not guaranteed optimal. No cut kerf, damage or end trim is assumed; include these in your supplied piece lengths.
Before you purchase
Use dimensions from your plan and properties from your chosen product. Any design spacing, section or fixing pattern must already be specified.
All product dimensions, coverage, density, allowances and joining rules must come from your supplied plan or selected product. No building-code values are inserted.
Method: dimensional arithmetic and user-supplied specifications. Software checks: 2026-10-05. Calculation and review policy.