|Corrosion Resistance||Superior weatherability and resistance to a broad range of chemicals.||Can cause galvanic corrosion.||Can warp, rot and decay from exposure to moisture, water and chemicals.
Coatings or preservatives required to increase corrosion or rot resistance can create hazardous waste and/or high maintenance.
|Weight||Very lightweight - about 70% the weight of aluminum on a density basis. Specific gravity = 1.7|
Pultruded fiberglass has significantly higher strength-to-weight ratio compared to both wood and aluminum
|Lightweight - about 1/3 that of copper or steel.||Specific gravity = .51 (oven dried).|
|Electric Conductivity||Non-conductive - high dielectric capability.||Conducts electricity - grounding potential.||Can be conductive when it is wet.|
|Thermal Conductivity||Insulates - low thermal conductivity.|
0.17 BTU/h-ft-F 5.0 x 10-6 in/in/°F
100 in. sample at a temperature change of 100°F = 0.05
|Heat conductor - high thermal conductivity.|
Pure Aluminum – 136.9 BTU/h-ft-F Alloyed Aluminum – 92.4 BTU/h-ft-F Thermal coefficient of expansion 11-13 (IN/IN/Fo)106.
|Insulates - low thermal conductivity.
Pine/Spruce/Fir/Larch/Mahogany (softwoods) – 0.08 BTU/h-ft-F Oak/Maple (hardwoods) – 0.09 BTU/h-ft-F Low thermal coefficient of expansion 2.5 (IN/IN/Fo)106.
|Strength||Ultimate flexural strength (Fu)|
LW = 30 ksi
CW = 10 ksi.
Compression strength is 30,000 psi.
Tensile Strength (KSI) 60.0
Modulus of Elasticity (PSI x 106) 3.0
Pultruded fiberglass has 86% of the yield strength of aluminum and, pound-for-pound's, stronger than aluminum in the lengthwise direction.
Stiffness: Pultruded fiberglass is approximately 1-1/2 times as rigid as wood. Modulus of elasticity LW = 2.5 x 106 psi, CW = .8 x 106 psi.
|Flexural strength (Fu) 35 ksi.||Extreme fiber bending = up to 2800 psi.*
Compression parallel to grain = up to 1800 psi.*
Stiffness: Modulus of elasticity = up to 1.8 x 106 psi.*
Deteriorates with age
|Finishing||Special colors available. Composite design can be customized for required finishes.||Silver color. Other colors require pre-finishes, anodic coatings and paints.||Must be primed and painted for colors. To maintain color, repainting and refinishing may be required.|
|Impact Resistance||Glass mat in pultruded fiberglass distributes impact load to prevent surface damage even in sub-zero temperatures. Will not permanently deform under impact.||Easily deforms under impact.||Permanently deforms or breaks under impact|
|Life expectancy||80+ years without any maintenance.||30 to 40 years less if exposed to a corrosive environment such as coastal environments and acidic rain.||15 to 20 years if properly maintained, sanded, sealed and refinished every year. Less if not properly maintained|