Landscape Fabric Calculator
Calculate how many rolls of landscape fabric (weed barrier) you need to cover a bed or area, including seam overlap.
Landscape Fabric Calculator (Rolls & Coverage) Guide
The landscape fabric calculator tells you how many rolls of weed-barrier fabric to buy to cover a bed or area. Enter the length and width, pick your roll size, and it adds a seam-overlap allowance and rounds up to whole rolls—so you're not left a strip short in the middle of the job.
How to Measure for Landscape Fabric
Multiply length × width to get the area in square feet, then add about 10% so adjacent strips can overlap by 3–6 inches at the seams (where weeds otherwise sneak through). Divide that by the coverage of one roll to get the number of rolls. For irregular beds, break the space into rectangles, add them up, and round up.
Woven vs. Non-Woven Fabric
Woven fabric is tough and breathable—ideal under gravel, rock, and pathways. Non-woven (spun) fabric drains faster and suits drainage and erosion projects. Either way, fabric belongs under your stone: pin it down, then spread material on top. Size that material with our decorative stone calculator or landscape stone calculator.
Frequently Asked Questions
How much landscape fabric do I need?
Measure the bed's length and width, multiply for square footage, then add about 10% for seam overlap. Divide by your roll's coverage (e.g., a 3 ft × 50 ft roll covers 150 sq ft). A 10 ft × 20 ft bed (200 sq ft) needs roughly 220 sq ft of fabric—two 150 sq ft rolls.
How much should landscape fabric overlap?
Overlap adjacent strips by 3–6 inches so weeds can't grow through the seams. The calculator's 10% allowance covers this for most rectangular beds; add more for long, narrow runs with many seams.
What is the difference between woven and non-woven landscape fabric?
Woven fabric is stronger and best under gravel, rock, and high-traffic paths. Non-woven fabric drains faster and is suited to drainage beds and erosion control. For decorative stone over soil, a heavy woven fabric usually lasts longest.
Does landscape fabric go under rock or mulch?
Fabric works well under rock and gravel, where it blocks weeds without breaking down. Under organic mulch it's less ideal, because the mulch decomposes into soil on top of the fabric and weeds root in that layer anyway.