Keep seam tape and perimeter tape separate.
Which taped runs belong in a carpet seam estimate?
Use the matching calculator
Use this decision sequence
- Count the parallel installed strips from an existing layout.
- Count joins between them as strips minus one.
- Multiply seam count by the actual joined length.
- Add perimeter tape only as a separate measured run if the specified installation uses it.
Keep the quantities distinct
| Quantity or assumption | How to use it |
|---|---|
| Seam tape | Runs between neighbouring strips. |
| Perimeter tape | Runs around specified boundary edges. |
| Coating masking tape | A separate temporary masking schedule. |
Worked comparison
Three parallel strips with 5 m joined lengths have 2 seams, giving 10 m of seam tape. With 10% allowance and 8 m tape rolls, the seam purchase is 2 rolls.
Check before using the estimate
A room perimeter is not the length of the joins inside that room.
All dimensions, product properties, prices and specifications in this example are illustrative arithmetic inputs. Use the values from your measured plan, selected product data sheet and supplier quote. This guide does not choose construction specifications or certify safety.
Calculation and scope checked 2026-10-04. Methods and scope.
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