Biaxial, triaxial or unidirectional: which stitched fiberglass fabric should I use?

Choose by where the loads in your part run. Put fibers along the main load with a unidirectional fabric, use 0°/90° biaxial for loads along and across the part, use ±45° biaxial for shear and torsion, and use triaxial when you need both in one layer. Stitched fabrics hold straight rovings in place with polyester stitching instead of weaving them^[1], and they are binder-free, so they suit a range of resins^[2].

0°/90° biaxial stitched fiberglass fabric — 0°/90° biaxial: rovings along and across the roll.

±45° biaxial stitched fiberglass fabric — ±45° biaxial: rovings on the diagonals, for shear and torsion.

What are the options?

Fabric	Fiber directions	Code family	Weight range (g/m²)
Unidirectional stitched	0° or 90°	EKUDL / EKUDT	126 to 1195^[3]
0°/90° biaxial	0° and 90°	EKLT / EKLTM	409.5 to 1381.5^[4]
±45° biaxial	+45° and −45°	EKBX / EKBXM	172 to 1257.6^[5]
Triaxial	0°/+45°/−45° or +45°/90°/−45°	EKTXL / EKTXT	453.2 to 1358.8^[6]
Woven roving combo mat	Woven roving + chopped strands	EKWRM	359.5 to 1762.71^[7]
Stitched chopped strand mat	Random	EKM	209.5 to 909.5^[8]

Heaviest listed weight per fabric type

Combo mat1,762.71 g/m²

0°/90° biaxial1,381.5 g/m²

Triaxial1,358.8 g/m²

±45° biaxial1,257.6 g/m²

Unidirectional1,195 g/m²

Stitched CSM909.5 g/m²

When should I use unidirectional fabric?

Use it for spar caps, stiffeners and any part loaded mostly in one direction. Unidirectional stitched fabric uses twistless rovings laid in the 0° or 90° direction^[9]. In the EKUDL 0° range, almost all the glass runs lengthwise; EKUDL800, for example, has 710 g/m² at 0° and 90 g/m² at 90°^[10].

When should I use 0°/90° biaxial?

Use it for panels, hulls and flat laminates loaded both along and across. It combines continuous rovings at 0° and 90° in one fabric, with or without a mat layer, for wind blades, marine panels, snowboards and truck and trailer panels^[11]. EKLT600 carries 330 g/m² at 0° and 270 g/m² at 90°^[12]. The EKLTM versions add a chopped layer, for example EKLTM600/300 with 300 g/m² of chop^[13].

When should I use ±45° biaxial?

Use it where the part twists or carries shear, such as the shear webs of a blade, hull frames and tubes. The rovings run at +45° and −45° in equal amounts; EKBX600 has 300.6 g/m² in each direction^[14].

When should I use triaxial?

Use it when you want axial and shear reinforcement from one ply and fewer layers to lay up. Triaxial fabric arranges rovings at 0°/+45°/−45° or +45°/90°/−45°^[15], and is mainly used in wind blades, shipbuilding and the automotive industry^[16].

What about combo mats?

A combo mat bonds woven roving to chopped strands with polyester stitching^[17]. It builds thickness and a good bond between layers in one step, which is why it is common in hand lay-up boat building.

TipDraw the main loads on your part first. Fibers along the load carry it; fibers at ±45° carry shear and twist. Then pick the fabric that puts glass where those arrows are.

What should I send for a quote?

The code (for example EKLT600 or EKBX450) or the weight per direction.
Whether you need a chopped mat or veil layer.
Roll width and length.
Resin system and process (hand lay-up, infusion, pultrusion).

The minimum order for these fabrics is 100 m²^[18]. Send your layup through the quote form, or compare the tables on the 0°/90° biaxial, ±45° biaxial and triaxial pages.