Questions?
(800) 748-5647
(800) 748-5647
Paramount Materials — Geosynthetics
Biaxial Geogrid
High-strength biaxial geogrid for base reinforcement and subgrade stabilization — it locks aggregate in place to spread loads, cut rutting, and extend the life of driveways, roads, and parking areas. Tensar BX1100 and BX1200 in full rolls, ready to ship.
- Type
- Biaxial (BX)
- Use
- Base & subgrade
- Shipping
- Free · all orders
01
What Is Biaxial Geogrid?
Overview
Biaxial geogrid is a rigid polymer grid engineered to reinforce aggregate over weak or unstable soils. It has near-equal tensile strength in both directions — lengthwise and crosswise — which is what the "biaxial" name refers to. That two-way strength lets it distribute loads evenly across a surface, making it ideal for flat applications like driveways, roads, parking lots, and building pads.
The grid is manufactured by punching a pattern of holes into a sheet of polypropylene and then stretching (drawing) it in both directions. This creates strong ribs and rigid junctions with open apertures. When aggregate is compacted over the grid, stone particles drop into and lock against those apertures — a mechanism called aggregate interlock. The result is a stiffer, stronger composite layer that behaves far better than unreinforced stone.
In practical terms, biaxial geogrid lets you build a stronger base with less stone, reduce rutting and settlement, and extend the service life of whatever you build on top. Paramount Materials stocks Tensar BX1100 and BX1200 biaxial geogrid in full rolls, ready to ship nationwide.
02
How Biaxial Geogrid Works
Mechanism
01 — Interlock
Aggregate locks in
As stone is compacted over the grid, particles partially penetrate the apertures and wedge against the ribs. The aggregate can no longer shift sideways, so the layer becomes a stiff, confined mass instead of loose stone.
02 — Confinement
Lateral movement stops
Confinement builds a stabilized zone above and around the grid. Wheel loads that would normally push stone outward are held in place, which is what prevents rutting and pumping in the base course.
03 — Load spread
Loads spread wider
Because the reinforced layer acts as one unit, it spreads each load over a wider area of the soil below. Lower stress on the subgrade means less deformation — even over soft or wet ground.
03
Biaxial vs. Uniaxial Geogrid
Compare
The difference comes down to the direction of strength. Biaxial geogrid is strong in two directions and is used for flat, horizontal reinforcement where loads come from above. Uniaxial geogrid is strong in one direction and is used for vertical applications like retaining walls and steep slopes, where the pull is along a single axis. Choosing the right one starts with the direction of the load.
| Biaxial Geogrid | Uniaxial Geogrid | |
|---|---|---|
| Strength direction | Two directions (length & width), roughly equal | One dominant direction (lengthwise) |
| Best for | Flat, horizontal loads — driveways, roads, lots, pads | Vertical loads — retaining walls, steep slopes, embankments |
| Primary function | Base reinforcement & subgrade stabilization | Soil reinforcement & earth retention |
| Aperture shape | Square / near-square | Elongated rectangular |
| Typical products | Tensar BX1100, BX1200 | Uniaxial (UX) geogrid rolls |
Building a wall or reinforcing a slope instead? See our Uniaxial Geogrid collection.
04
What Biaxial Geogrid Is Used For
Applications
Gravel driveways
Reinforces the base under a gravel driveway so it resists rutting and potholing, even over soft ground — a long-lasting fix for a driveway that keeps sinking or washing out.
Roads & haul routes
Stabilizes the aggregate base under paved and unpaved roads, access roads, and construction haul routes, reducing stone requirements and extending pavement life.
Parking lots & pads
Creates a stable, load-bearing base for parking areas, equipment yards, and building pads where heavy or repeated loads would otherwise deform the ground.
Subgrade stabilization
Bridges soft, wet, or unstable subgrade soils so you can build on ground that would otherwise need excavation and replacement — the classic base-over-weak-soil fix.
05
How to Install Biaxial Geogrid
Installation
Installation is straightforward and follows the same basic sequence whether you're building a driveway, a road, or a parking pad. Always follow the manufacturer's guidelines and any project engineer's specification for your site.
1
Prepare the subgrade
Clear the area and grade it to a smooth, uniform surface. Remove large debris and roots. There's no need to over-excavate soft soil — bridging weak subgrade is exactly what the grid is for.
2
Roll out the geogrid
Unroll the biaxial geogrid directly over the prepared subgrade with the ribs flat and taut. Keep it wrinkle-free so the apertures stay open for aggregate to lock into.
3
Overlap the seams
Overlap adjacent rolls and ends — typically 12 to 36 inches depending on subgrade strength and the spec. Overlap more over softer soils. On very weak ground, seams can be tied or staked to hold position during placement.
4
Place & compact aggregate
Spread aggregate over the grid by back-dumping and pushing stone out ahead of the truck — never drive directly on the exposed grid. Compact in lifts to lock the stone into the apertures and build the reinforced base.
How much do you need? Measure the area to reinforce in square feet and add for overlaps. One roll of BX1100 covers 4,100 sq ft (12.5' × 328') and one roll of BX1200 covers 3,075 sq ft (12.5' × 246'). Not sure which spec fits your project? Use our Geogrid Spec Finder.
06
Choosing Between Tensar BX1100 and BX1200
Products
Both are punched-and-drawn biaxial geogrids from Tensar. BX1100 is the standard-strength grid for typical driveway and light base-reinforcement work. BX1200 is the higher-strength grid for heavier loads and softer subgrades — the more common choice for roads, commercial lots, and demanding subgrade stabilization. Pricing is listed live on each product page.
Standard strength
Tensar BX1100 Biaxial Geogrid
12.5' × 328' roll · 4,100 sq ft. Ideal for gravel driveways and typical base reinforcement.
View product & pricing
Higher strength
Tensar BX1200 Biaxial Geogrid
12.5' × 246' roll · 3,075 sq ft. For heavier loads, roads, lots, and softer subgrades.
View product & pricing
07
Biaxial Geogrid FAQ
Questions
What is biaxial geogrid used for?
Biaxial geogrid is used to reinforce the aggregate base under flat, horizontally loaded surfaces — gravel driveways, roads, parking lots, equipment yards, and building pads. It's also used for subgrade stabilization, bridging soft or wet soils so you can build over ground that would otherwise be too weak.
How does biaxial geogrid work?
When aggregate is compacted over the grid, stone particles lock into the grid's open apertures — a mechanism called aggregate interlock. This confines the stone so it can't shift sideways, creating a stiff reinforced layer that spreads loads over a wider area and reduces rutting and settlement.
What's the difference between biaxial and uniaxial geogrid?
Biaxial geogrid has roughly equal strength in two directions and is used for flat, horizontal applications where load comes from above, like driveways and roads. Uniaxial geogrid is strong in one direction and is used for vertical applications like retaining walls and steep slopes. The direction of the load determines which one you need.
Is biaxial geogrid good for a gravel driveway?
Yes — it's one of the most common uses. Placed under the gravel base, biaxial geogrid keeps stone from spreading and sinking into soft soil, which prevents ruts and potholes and greatly extends the life of the driveway. It's especially effective on driveways that keep washing out or sinking.
How much biaxial geogrid do I need?
Measure the area you want to reinforce in square feet and add extra for overlaps at seams (typically 12–36 inches). One roll of Tensar BX1100 covers 4,100 sq ft and one roll of BX1200 covers 3,075 sq ft. If you're unsure which grade or how much, use our Geogrid Spec Finder or request a quote.
Should I use BX1100 or BX1200?
BX1100 is the standard-strength grid for typical driveways and light base reinforcement. BX1200 is higher-strength for heavier loads and softer subgrades, and is the more common choice for roads, commercial parking lots, and demanding subgrade stabilization. When in doubt for heavy or soft-soil sites, step up to BX1200.
Does biaxial geogrid need a geotextile fabric too?
They do different jobs and are often used together. Geogrid reinforces and stabilizes the aggregate, while a woven or nonwoven geotextile separates the aggregate from the subgrade soil and helps with filtration. On very soft or muddy subgrades, pairing a separation geotextile under the geogrid gives the best long-term performance.
Not Sure Which Geogrid You Need?
Match the right grade and roll size to your driveway, road, or subgrade project. Pricing for both rolls is listed right on the site; need a volume quote or help with a large job? Request one below.
Free shipping on every order