Buying geotextile fabric online can feel overwhelming if you're not sure what you're looking at. Weight ratings, roll widths, AOS specs, woven versus non-woven — there's a lot of terminology and the wrong choice can mean a clogged french drain or a driveway that sinks after the first winter.

This guide cuts through the confusion. Whether you're lining a french drain, wrapping a retaining wall, stabilizing a gravel driveway, or placing fabric under pavers, you'll find exactly what to order and why.

What Is Geotextile Fabric?

Geotextile fabric is a permeable synthetic material used in civil and landscape engineering to separate, filter, reinforce, protect, or drain. It's manufactured from polypropylene or polyester fibers in one of two ways: woven (like a very tight mesh) or non-woven (needle-punched fibers bonded together).

Unlike the thin black weed barrier fabric you find at garden centers, professional geotextile fabric has rated technical specifications — measured permeability, apparent opening size (AOS), grab tensile strength — that ensure it actually performs its intended function for years underground.

It's used in a wide range of applications:

• Lining french drain trenches and drainage beds
• Wrapping retaining wall drainage aggregate
• Separating subgrade soil from gravel driveways and road base
• Lining septic leach fields
• Stabilizing soft ground beneath structures
• Controlling erosion on slopes

Non-Woven vs. Woven: Which Type Do You Need?

This is the most important decision you'll make when buying geotextile fabric. Getting this wrong means buying the wrong product entirely.

Feature	Non-Woven	Woven
Primary function	Drainage filtration — lets water through, blocks soil	Soil separation and stabilization — prevents mixing under load
Water flow	High permeability	Lower permeability (not ideal for drainage)
Tensile strength	Moderate	High — resists tearing under heavy load
Texture	Felt-like, fuzzy	Smooth, mesh-like
Best for	French drains, retaining walls, septic fields, dry wells	Driveways, road base, gravel stabilization, heavy-load applications

Choosing the Right Weight (oz)

Geotextile fabric is sold by weight, measured in ounces per square yard (oz/sy). Heavier fabric is thicker, stronger, and — in the case of non-woven fabric — provides finer filtration. Here's a practical quick-reference table:

Weight	Type	Best Applications
3 oz	Non-woven	Light filtration, drain pipe sock wrap, sandy soils
4 oz	Non-woven	French drains (sandy/loamy soil), dry wells, retaining wall drainage — most common residential weight
6 oz	Non-woven	French drains in clay soil, retaining walls with high silt, leach fields, commercial drainage
8 oz	Non-woven	DOT drainage projects, high-silt environments, heavy-duty drainage applications
Standard grade	Woven	Residential driveways, gravel parking areas, light vehicle traffic
Intermediate grade	Woven	Farm lanes, moderate truck traffic, soft subgrade
Heavy-duty grade	Woven	Road construction, heavy truck traffic, DOT projects

When in doubt for drainage: Use 4oz for sandy or loamy soils and 6oz for clay-heavy soils. For driveway and road base stabilization, start with standard-grade woven and step up if you have heavy traffic or very soft ground.

Understanding Roll Sizes

Geotextile fabric is typically sold in rolls. Roll dimensions are expressed as width × length (for example, 6' × 100' or 12.5' × 300'). Here's what you need to know:

Standard Roll Widths

Non-woven geotextile for residential drainage is commonly sold in rolls 3', 4', 6', 12.5', or 15' wide. Wider rolls are more efficient for large area coverage. Narrower rolls work well for trench-lining applications like french drains where you want the fabric to wrap the trench walls and fold over the top without excess waste.

Standard Roll Lengths

Common roll lengths are 100', 150', 200', 300', and 360'. Longer rolls mean fewer seams and less waste on large projects. For small residential projects, shorter cut lengths are often available so you don't have to purchase more than you need.

Buying by the Linear Foot

For smaller projects, many suppliers — including Pro Fabric Supply — sell fabric by the linear foot from a standard roll width. This is ideal for a single french drain run or a small retaining wall where a full roll would be too much.

Roll Format	Best For
By the linear foot	Single french drains, small retaining walls, patching
Short roll (100–150 ft)	Residential yard drainage, small driveway projects
Full roll (300–360 ft)	Contractors, large driveways, road base, commercial projects

How to Calculate How Much You Need

Getting the quantity right before you order saves you from making a second trip — or from having 200 feet of fabric left over at the end of a job.

For French Drain Trenches

The fabric needs to line the bottom and both walls of the trench, plus fold over the top to close the envelope. Use this formula:

• Required width = trench depth × 2 + trench width + 12 to 24 inches for overlap
• Required length = trench length + 5 to 10 percent for overlap and adjustments

Example: A 50-foot french drain trench that is 18 inches wide and 24 inches deep needs fabric approximately 7 to 8 feet wide and 52 to 55 feet long. A 6' × 100' roll would cover this with room to spare, or you could order 55 linear feet from a roll that is 7.5' wide.

For Retaining Walls

Fabric is placed behind the wall to wrap the drainage aggregate. Calculate the height of the wall × the wall length, then add 20 to 25 percent for overlaps and folds at the top and bottom.

For Driveways and Road Base

For woven geotextile placed flat on the subgrade before aggregate is added, calculate the total square footage of the area and add 10 to 15 percent for overlaps between adjacent strips (typically 12 to 18 inches of overlap at each seam).

Key Specs to Look For

When comparing geotextile fabric products online, these are the specifications that actually matter:

Spec	What It Means	Why It Matters
Weight (oz/sy)	Ounces per square yard	Indicates thickness, strength, and filtration level
AOS (Apparent Opening Size)	The largest particle size that can pass through the fabric	Controls how fine of soil particles the fabric blocks — critical for clay soils
Permittivity	How fast water moves through the fabric (per second)	Ensures the fabric won't restrict drainage flow
Grab Tensile Strength	Pounds of force required to tear the fabric	Determines how well it survives installation and load
Puncture Resistance	Resistance to puncture from aggregate or roots	Important for coarse gravel applications
UV Stability	Resistance to UV degradation	Only matters if fabric will be exposed — buried fabric is not affected

For most residential drainage applications, you don't need to dig deep into every spec — choosing the right weight and type covers 90 percent of it. The specs above become more important for commercial, DOT, or engineered applications where the fabric needs to meet a specific standard.

Where to Buy Geotextile Fabric Online

Big box hardware stores typically carry one or two options — usually a lightweight non-woven or a generic woven — with limited width and length choices and no technical specs listed. If your project requires a specific weight, width, or a larger quantity, you'll almost certainly need to buy online from a specialty supplier.

When shopping online for geotextile fabric, here's what to look for in a supplier:

• Full spec sheets available — weight, AOS, permittivity, and tensile strength should be listed or downloadable
• Multiple weights stocked — 4oz through 8oz non-woven and multiple woven grades
• Multiple roll sizes — ability to buy by the foot, short rolls, or full rolls
• Clear application guidance — the supplier should help you choose the right product, not just list specs
• Ships fast — geotextile fabric is a project-ready item; you shouldn't wait weeks

Pro Fabric Supply stocks non-woven geotextile fabric from 3oz through 8oz and woven stabilization fabric in standard, intermediate, and heavy-duty grades. You can buy by the linear foot for small projects or order full rolls for larger jobs.

Frequently Asked Questions

Where can I buy geotextile fabric?

Geotextile fabric is available from specialty suppliers online, including Pro Fabric Supply. Buying online gives you access to the full range of weights, widths, and roll lengths that most local hardware stores do not carry. You can order by the linear foot for small projects or by the full roll for larger jobs.

How much geotextile fabric do I need?

Measure the length and width of your installation area and add 12 to 18 inches on each side for overlap and folding. For a french drain trench, you need fabric wide enough to line the bottom, both walls, and fold over the top — typically trench depth × 2 plus trench width plus 12 to 24 inches. Always add 10 to 15 percent to your total for waste and adjustments.

What weight geotextile fabric should I buy?

For most residential drainage applications in sandy or loamy soil, 4oz non-woven is the standard choice. For clay soils or heavier filtration requirements, use 6oz. For driveway and road base stabilization, use woven geotextile in standard or intermediate grade depending on traffic load.

What is the difference between geotextile fabric and landscape fabric?

Geotextile fabric is an engineered product with rated permeability, AOS, and tensile strength specifications — designed for drainage filtration, soil separation, and stabilization. Landscape fabric (weed barrier) is typically a lighter woven or spun product designed primarily for weed suppression, with less predictable drainage performance and lower durability.

Can I buy geotextile fabric by the foot instead of a full roll?

Yes. Pro Fabric Supply sells geotextile fabric by the linear foot from standard roll widths, so you can order exactly what your project requires. This is ideal for smaller residential projects like a single french drain run or a backyard retaining wall where a full roll would be unnecessary.