Moulded vs Pultruded GRP Grating: Which to Choose

GRP grating comes in two main types: moulded and pultruded. They look similar but are made very differently, and choosing the right one affects strength, span, cost and where the grating can safely be used. This guide explains the difference so you can specify with confidence.

Moulded GRP grating

Moulded grating is made by laying continuous glass fibre rovings into a mould in both directions, then saturating them with resin and curing. Because the glass runs both ways, the panel has bi-directional strength, which means it carries load evenly in either direction. The one-piece construction also gives excellent corrosion resistance, as there are no joints for moisture or chemicals to attack.

Moulded grating usually has a gritted anti-slip top as standard, is more economical, and suits walkways, platforms, walk-over areas and trench covers over short to medium spans. Our GRP grating panels are moulded and available in 25mm, 38mm and 50mm depths.

Pultruded GRP grating

Pultruded grating is built from high-strength load-bearing bars produced by pulling glass fibres through a resin bath and a heated die, then assembling those bars with cross rods. The glass runs mainly along the bars, so pultruded grating has very high strength in one direction and a high strength-to-weight ratio. This lets it span further between supports with less deflection.

Pultruded grating tends to cost more and is chosen where long unsupported spans or higher loads are needed, such as longer walkways and structural platforms.

Moulded vs pultruded: at a glance

Which should you choose?

For most walkways, access platforms and trench covers with supports at sensible centres, moulded grating is the practical, cost-effective choice and is anti-slip as standard. Choose pultruded grating when you need to span further between supports or carry heavier loads with minimal deflection. The correct panel depth always depends on the span and the load, so check the load and span figures before you order.

If you are unsure which type or depth suits your project, call our team on 01480 570001 or email info@safetyproductsdirect.co.uk and we will help you specify it, and cut the panels to size before delivery.

Frequently asked questions

Is moulded or pultruded grating stronger?

Pultruded grating is stronger in its load-bar direction and can span further, while moulded grating carries load evenly in both directions. The best choice depends on your span and how the grating is supported.

Which is more corrosion resistant?

Both resist corrosion well. Moulded grating has a one-piece construction with no joints, which gives it an edge in very wet, marine or chemical environments.

Can GRP grating be cut to size?

Yes. We cut grating panels to your dimensions in house so they drop straight into your opening, and we supply the fixing clips to secure them.

Related products and guides

• Browse our GRP grating panels, cut to size free with fast UK delivery
• See GRP grating panel prices and sizes
• Guide: What is GRP grating and why is it used?