An FRP H beam is a pultruded fiberglass structural profile shaped like a steel H beam or wide-flange beam, built to carry the same kind of load without rusting, conducting electricity, or needing paint.
It is made from continuous glass fibers pulled through a resin bath and cured into a fixed H-shaped cross-section, which is why the industry also calls it a pultruded fiberglass reinforced H beam or FRP structural H beam.
Key takeaways:
An FRP H beam weighs roughly 75% less than a steel beam of the same size, with a typical density of 107-120 lb/ft³ versus about 490 lb/ft³ for steel
Standard profiles run from about 4 inches to 24 inches in height/width, with flange thicknesses of 0.24-1 inch and stock lengths of 10-40 feet
It won’t corrode, rot, or conduct electricity, and flame-retardant resin systems meet ASTM E-84 and UL 94 V-0 ratings
A reliable FRP H beam supplier should hold stock sizes on hand, supply engineering data, and be able to fabricate custom lengths without pushing your project onto a long lead time.
DEFI Fiberglass stocks and fabricates FRP H beams and wide-flange profiles from its Houston and Lafayette, Louisiana plants for industrial, petrochemical, and water treatment projects.
What Is an FRP H Beam Made Of?
An FRP H beam is a composite of fiberglass reinforcement and thermosetting resin, built in layers (laminates) rather than a single material. Each layer does a different job:
Chemical Barrier Layer (CBL): gives the beam its anti-corrosive surface.
Structural Layer: carries the load and provides temperature resistance.
Topcoat (surface veil): shields the laminate from UV and environmental wear.
The resin system also determines the fire performance. Polyester and vinyl ester structural shapes commonly carry a flame spread rating of 25 or less under ASTM test method E-84, and fire-retardant formulations meet UL 94 V-0 and are listed as self-extinguishing under ASTM D-635. DEFI’s own FRP products are formulated to be flame-retardant and self-extinguish once the flame source is removed.
FRP H Beam Specifications and Standard Sizes
FRP H beams are not sold in a single size; they follow a published range of dimensions so engineers can substitute them into existing steel-beam layouts. The typical range looks like this:
Dimension | Typical Range |
|---|---|
Height (H) and width (B) | 100 mm, 600 mm (4 in, 24 in) |
Flange thickness (T) | 6 mm, 25 mm (0.24 in, 1 in) |
Web thickness (t) | 5 mm, 20 mm (0.2 in, 0.8 in) |
Standard length | 3 m, 12 m (10 ft, 40 ft), custom-cut available |
Wide-flange and I-beam shapes are usually quoted in stock increments. Wide-flange sizes from 3 x 3 x 1/4 in up to 8 x 8 x 3/8 in, and I-beam sizes from 3 x 1-1/2 x 1/4 in up to 10 x 8-1/2 x 3/8 in, each available in fire-retardant polyester or vinyl ester resin systems. Because section depth and flange width both affect load capacity, a reliable fiberglass H beam supplier should confirm your span, load, and environment before quoting a size rather than selling off a size chart alone.
FRP H Beam vs. Steel H Beam
An FRP H beam trades raw stiffness for weight savings, corrosion resistance, and lower lifecycle cost; a steel H beam is stiffer out of the box but corrodes, conducts electricity, and costs more to move and maintain over time.
Factor | FRP H Beam | Steel H Beam |
|---|---|---|
Density | ~107-120 lb/ft³ | ~490 lb/ft³ |
Weight vs. steel | About 75% lighter | Baseline |
Corrosion resistance | Will not rust or corrode | Corrodes with moisture/chemical exposure |
Electrical conductivity | Non-conductive (dielectric strength ~35 kV/in lengthwise) | Conductive |
Installation equipment | Hand tools, no crane needed | Often requires heavy lifting equipment |
Maintenance | Virtually maintenance-free | Requires painting/coating upkeep |
Because an FRP H beam is so much lighter, crews can carry and position it with standard hand tools instead of cranes or riggers, which cuts both labor time and freight cost on a project.
Why Businesses Are Switching to FRP H Beams
Design Freedom
Steel’s weight forces compromises: heavier structures need thicker concrete foundations just to carry the load. Because an FRP H beam is a fraction of the weight, designers can build complex walkways, ladder cages, or platforms without that foundation penalty.
Logistics and Handling
Lighter beams mean cheaper freight and no need for flatbed trucks or cranes on site, which keeps install costs down on multi-beam projects.
Corrosion and Chemical Resistance
FRP is unaffected by saltwater, acids, and most industrial chemicals that eat through steel in a matter of weeks. That is why it shows up heavily in chemical plants, refineries, water treatment facilities, and marine structures.
Safety Features
Non-conductive by nature, FRP H beams reduce shock risk around electrical equipment. Grit or textured surfaces can also be built into related FRP components for slip resistance, and bright resin colors improve visibility in low-light work areas.
Industries relying on these advantages most include petrochemical plants, water and wastewater treatment facilities, offshore platforms, and amusement parks, anywhere corrosion or electrical hazard would shorten a steel structure’s life.
How to Choose a Reliable FRP H Beam Supplier
A reliable fiberglass H beam supplier should be able to show four things before you commit to an order:
Stock on hand. Standard wide-flange and H-beam sizes should already be in inventory, not a 10-week lead item.
Engineering data. Tensile, flexural, and shear properties for the resin system you need, so your engineer can size the beam correctly.
Fabrication capability. The ability to cut, drill, and assemble custom lengths and connections, not just ship raw stock.
Track record in your industry. Experience supplying petrochemical, marine, or water treatment projects where the beam will actually be exposed to the chemicals or weather you’re designing for.
A supplier that only sells off a price list, without asking about your load, span, or environment, is a sign to keep shopping.
Upgrade Your Structures With FRP H Beams From DEFI
DEFI Fiberglass designs, stocks, and fabricates FRP H beams and wide-flange profiles from its plants in Houston, Texas, and Youngsville, Louisiana. Decades of fabrication experience and inventory levels that rival a manufacturer’s let DEFI quote and ship standard and custom H-beam sizes without the long wait common across the industry.
For a deeper look at how structural shapes like H beams, I-beams, and channels are engineered, see our complete guide to FRP structural profiles and what structural FRP is. If your project also needs embed angles to anchor grating into concrete, our FRP embed angle guide covers sizing and installation.
Contact us today to see what we can build for your business.
FAQ
What is an FRP H beam used for?
FRP H beams support walkways, catwalks, platforms, ladder cages, and structural framing in corrosive or electrically hazardous environments, including chemical plants, water treatment facilities, and offshore platforms.
How much does an FRP H beam weigh compared to a steel H beam?
An FRP H beam weighs about 75% less than a steel beam of the same size, with a density around 107-120 lb/ft³ versus roughly 490 lb/ft³ for steel.
What sizes do FRP H beams come in?
Standard profiles typically range from 4 inches to 24 inches in height and width, with flange thicknesses from 0.24 to 1 inch and stock lengths from 10 to 40 feet, though custom cuts and sizes are available from most fabricators.
Is an FRP H beam as strong as a steel H beam?
Pound for pound, pultruded FRP is comparable in strength to steel, but because it isn’t a direct one-for-one swap, a fiberglass beam may need to be deeper or thicker than the steel section it replaces to carry the same load.
How do I find a reliable FRP H beam supplier?
Look for a supplier that keeps standard sizes in stock, provides engineering and resin data, fabricates custom lengths, and has a track record in your specific industry rather than one that just quotes off a size chart.
Can FRP H beams be installed with standard tools?
Yes. Because FRP is lightweight, it can be cut, drilled, and assembled with hand tools such as drills and circular saws, without cranes or heavy rigging equipment.
What’s the difference between an FRP H beam and an FRP I beam?
Both are pultruded structural profiles with similar manufacturing, but an H beam has flanges roughly equal in width to its depth, while an I-beam typically has narrower flanges, which changes how each distributes load across a span.
