Many people out there don’t know the advantages of aluminum boats over Glass Reinforced Plastic (GRP) boats, so here we will highlight some of them:

Aluminium boats have the longest life span among other materials, due to its characteristics and the alloy which have been developed over the past 50 years. The alloy 5000 and 6000 series which are mainly used in boats building are known for their high strength and corrosion resistance, and yet have good elasticity to absorb impacts. Usually a good aluminium boat can live 30-40 years easily with regular checkup and little maintenance. Changing sacrificial anodes regularly and maintaining good electricity circuits with no leakage keeps the body in its original state.

Aluminium boats are lighter 30% than regular GRP boats, which means less fuel consumption and higher speeds achievements. Aluminium is known for its high strength to weight ratio than all materials used in boat building. 

GRP material is extremely brittle and is thus subject to cracking and fracture during high impacts while aluminium has considerable ductility, i.e., the ability to withstand permanent deformation without rupture. This is because aluminium has low modulus of elasticity, thus it absorbs the energy of any impact and nothing happens to body.

Aluminium is not affected by ultra violet rays, while GRP is chemically still reacting and gets higher solidity with time, which leads to high point of brittleness and could splash if got a hit.

Aluminium does not burn. GRP boats contain petroleum based resins which burn energetically. Fire retardant resin makes them harder to "light", but nonetheless the burning is energetic once started. 

Most of GRP boats have moisture content in the structure which causes dislamination and sometimes expiry of the boat life time! This is the main reason why the life time of an aluminum boat is about double that of the GRP.

Some applications cannot be made with GRP, like for instance, Semi Submersible boat. Why?

Because GRP structure could deform (under pressure), and eventually crack, especially under water near glass edges and so the boat will sink.

Military boats are mostly made of aluminium because fixing a bullet hole only needs a plug! While in case of GRP the bullet usually causes big holes and fractures which could not be fixed in battle.

Landing Crafts are mostly (if not all) are made of aluminium because when ramp hits small rocks or stones on shores and rough surfaces could only make minor scratches or buckles, where in GRP this could damage the ramp and the boat could not do the job.