Bathtubs are made from a variety of materials. Cast iron and acrylic are two popular materials used. Acrylic bathtubs are more widely used in newer homes but some consumers still opt for the strength and durability of a cast-iron bathtub. Both types of bathtubs have their advantages and disadvantages.
Fiberglass reinforces acrylic sheets in the production of acrylic types of bathtubs. The finished product is relatively crack and chip resistant. Acrylic tubs are made out of a synthetic material and can be made in a variety of colors.
Cast iron bathtubs are made by pouring iron into molds, then letting it cool and harden. This type of tub is very resistant to chemicals and is nearly impossible to scratch or dent. They usually have an enamel coating on them and are fire polished to give them a smooth appearance.
Cast iron bathtubs are usually a little more expensive than acrylic tubs. As of 2009, a "cheap" acrylic tub costs around $400 and a top-of-the-line acrylic tub can cost upwards of $4,000. A brand new cast iron bathtub can cost anywhere from $1,200 to $5,000, installed.
Cast iron bathtubs are far heavier than acrylic bathtubs which makes them difficult to install; several people will be needed to conduct the installation of a cast iron tub. The floor underneath a cast iron tub may have to be reinforced because it is so heavy. Acrylic bathtubs are easier to install than cast iron tubs because they are not nearly as heavy.
Cast iron bathtubs are very durable--with proper maintenance, they can last for generations. They require less upkeep than acrylic and may be the proper choice for bathrooms that receive a lot of traffic. Acrylic bathtubs are also durable but they are not indestructible. Cheap acrylic bathtubs can warp and crack if not properly maintained or are poorly installed. Acrylic bathtubs are more prone to staining than cast iron bathtubs, which means that a more rigorous cleaning schedule should be followed with acrylic.
Cast iron is known for its ability to absorb heat and also transfer it. A cast iron tub can keep a hot bath warmer for longer than an acrylic one will. Even though a cast iron tub can be cold to the touch, as soon as it is filled with warm water, heat transfer begins. Acrylic bathtubs are made from a synthetic material that does not transfer heat well. When filled with warm water, they retain heat to some degree but not as well as a cast iron tub.