The HULL

The hull is the part of your boat that makes it float, so it must be in good condition. The material the hull is made of influences the type of maintenance it needs.

The most common materials used are:
•    Wood
•    Fiberglass (GRP - Glass-Reinforced Plastic = glass fiber + epoxy resins)
•    Metal (steel, aluminum)

Wood – marine plywood (compensato marino), teak
Advantages (vantaggi): Natural, traditional;  easy to repair
Disadvantages (svantaggi): Each type of wood needs specific care. Problems with rotting (marcire) , molding (muffa), damage from the sun and atmospheric conditions; water leakage (fare acqua) where screws (viti) are and between planks (tavole); screws can rust (arrugginire) and need to be replaced (sostituire).

Things you must do often for wood boat maintenance:

• sand (sabbiare)
• replace rusted metal objects
• fill (riempire) holes
• revarnish (riverniciare)
• repaint (ripitturare)
• apply anti-fouling paint on the underwater body (applicare anitivegetitivo nel pescaggio)

Fiberglass
Advantages: Cheap, durable, easy to maintain. Largely free of corrosion.
Disadvantages: Physical pressure, exposure to sunlight and rusty screws can cause cracking (spaccature), bumps (bozzi), bubbles (bolle) and scratches (graffi); osmosis; not fireproof (non ignifugo). 

Notes: A final gel coating is usually used to protect the underlying structures and laminate. This gives it a shiny finish that needs to be cleaned (pulire) and polished (lucidare). 
If the gel coat is damaged, water can get in between the coat and the laminate, which will cause the coat to peel off (scrostare). Gel coat can also be used for small repairs.

Metal – aluminum and steel
Advantages: Durable, require less work than wooden hulls
Disadvantages: Rust; in constant need of paint; bilges (stive) need careful maintenance

Aluminum 
Advantages: Lightweight (leggero) and strong; easy maintenance. If it is not painted, it  to an elegant gray.
Disadvantages: Maintenance is expensive because it requires special tools (atrezzature) and techniques. It is difficult to weld.  Corrosion is a problem, particularly below the waterline.

Steel
Advantages: More durable and rusts less than iron (ferro).
Disadvantages: Rust is a problem, unless protected by paint.

Notes: Modern steel components are welded (saldare) or bolted (imbullonare). The hull is sandblasted (sabbiare) to have a clean surface.  A zinc layer (strato di zinco) is often applied to coat (coprire) the entire hull before painting (vernicatura).   Lead (piombo) paint is usually used. A hammer (martello) is used to remove large patches of rust (incrostazioni di ruggine).  
Maintenance work for steel and wooden hulls is very similar. Like wood, most have a finishing layer of paint.