Non-Woven Geotextile Drainage Fabric | Sizes, Specs, Prices

Nonwoven geotextile can be made in several ways, but most is needle-punched: a mat of short synthetic fibres is passed through boards of barbed needles that push the fibres through each other and lock them into a felt-like fabric.

Non-woven geotextile is a permeable fabric, usually made from polypropylene or polyester, used for drainage, filtration, separation and erosion control. Because the fibres form a thick, open web, water passes through the fabric quickly while soil particles are held back. That is why it is the standard filter wrap around drains.

Non-Woven Geotextile Fabric Weight Categories:

Weights below are in ounces per square yard (oz), as many charts quote them. In India the same fabric is specified in GSM (grams per square metre); 1 oz/sq yd is about 34 GSM.

Lightweight (2 oz. to 3 oz)

About 70–100 GSM. High flow rates, cushioning under-layers and drain-field applications. The 3 oz weight is often used behind retaining walls as a filter between the backfill soil and the drainage gravel.

Medium weight (4 oz. to 6 oz)

About 135–200 GSM. A medium-weight non-woven fabric lets water through without washing out the soil behind it. It is used for erosion control, separation and drainage (French drains), and under gravel paths as a separation layer between the gravel and the soil underneath.

Heavyweight (8 oz. to 16 oz)

About 270–540 GSM. Heavyweight non-woven fabrics are used where the fabric must resist puncture and survive rough installation: behind large rip-rap, and as a cushion layer under or over a geomembrane in containment ponds and artificial lakes. At the upper end of the range (10 oz +) the extra thickness noticeably lowers the flow rate through the fabric (its permittivity, tested to ASTM D4491), so check that value if drainage is the main function.
Heavy non-woven is also used as a separation layer for sand under volleyball courts (8 oz), and to stop ballast mixing with the soil beneath railway tracks (16 oz).

Non Woven Geotextile Specification Charts

Non-Woven Geotextile characteristics

• Polypropylene fibres
• Needle-punched construction
• Rot-resistant fabric

Non-Woven Geotextile advantages

• Stable, dimensionally consistent fabric
• Suited to filtration and drainage
• Available in a range of weights and strengths

How much does geotextile fabric cost?

Geotextile prices vary widely with type, weight and roll size. As an indicative range, a roll of low-grade fabric can cost around Rs.15000, while a roll of high-strength woven geotextile can cost upwards of Rs.2L. Prices change with polymer rates and order quantity, so ask for a current quote against your GSM and roll size.

Does water go through geotextile fabric?

Yes. Needle-punched and spunbonded non-woven geotextiles let water flow through easily, which is why they are used for landscaping drainage, filtration and ground stabilisation.

Nonwoven Geotextile Filter Fabric and further Applications

The right weight of non-woven filter fabric depends on the application.

Lighter fabrics, such as 4 oz non-woven geotextile, are used in drainage and landscaping. A light non-woven paving fabric saturated with bitumen tack coat is also laid between asphalt layers to slow reflective cracking. Medium-weight fabrics, such as 6 oz and 8 oz non-woven geotextile, are used for stabilisation, erosion control and sewer and drainage works.

Drainage is the most common use. Non-woven filter fabric is wrapped around French drains and underground drains to keep silt out while letting water in. Heavyweight fabrics, such as 10 oz non-woven geotextile, go where strength matters: road stabilisation and geomembrane cushioning.

Ocean Geosynthetics supplies both woven and nonwoven geotextile and can recommend a grade for your application. See also does water go through geotextile fabric?