Unlike Steel which will rust when exposed to weathering and chemicals, fiberglass structural shapes are highly corrosion resistant. Features of both pultrusions and steel structural shapes are compared on a point-for-point basis below.
| COMPARE! |
Pultruded Fiberglass Structural Shapes |
Steel A-36 Carbon |
CORROSION RESISTANCE |
Pultrusions are available in either polyester or vinyl ester resin for resistance to a broad range of chemicals.
Painting required only when exposed to direct sunlight. |
Subject to oxidation and corrosion. Requires painting or galvanizing for many applications. |
| WEIGHT |
Lightweight - weighs 75% less than steel.
1/2" thick plate = 4.7 lbs./sq. ft. |
Could require lifting equipment to move and place.
1/2" thick plate = 20.4 lbs./sq. ft. |
| CONDUCTIVITY |
Does not conduct electricity.
Low Thermal Conductivity 4 (BTU/SF/HR/Fo/IN). |
Conducts electricity. Grounding potential.
Thermal Conductivity 260-460 (BTU/SF/HR/Fo/IN). |
| STRENGTH |
Pultrusions have a high strength-to-weight ratio, and pound-for-pound are stronger than steel in the lengthwise direction.
Ultimate flexural strength (Fu) LW = 30 ksi CW = 10 ksi |
Homogeneous material.
Yield strength (Fy) 36 ksi |
| STIFFNESS |
Modulus of elasticity LW = 2.5 x 106 psi CW = .8 x 106 psi
Will not permanently deform under working load. |
Modulus of elasticity 29 x 106 psi |
| IMPACT RESISTANCE |
Glass mat in pultruded parts, distributes impact load to prevent surface damage even in sub-zero temperatures. Will not permanently deform under impact. |
Can permanently deform under impact. |
| EMI/RFI TRANSPARENCY |
Transparent to EMI/RFI transmissions. |
Can interfere with EMI/RFI transmissions. |
| VERSATILITY |
Pigments added to the resin provide color throughout the part. Special colors available. |
Must be painted for color. To maintain color and corrosion resistance, repainting may be required. |
| EASY FIELD FABRICATION |
Pultruded fiberglass can be field fabricated using simple carpenter tools with carbon or diamond tip blades.
Lightweight for easier erection and installation. |
Often requires welding and cutting torches.
Heavier material requires special handling equipment to erect and install. |
| COST |
Lower installation and maintenance costs in industrial applications often equals lower lifecycle costs. |
Lower initial material cost. |