What are Bathtubs Made of? Bathtub Materials: Pros & Cons

Fiberglass, also called glass-reinforced plastic, is one of the cheapest bathtub materials. It’s a reinforced plastic that’s poured into a bathtub-shaped mold, resin-coated, and then polished. It can last a couple of years before scratches and cracks affect it. Some manufacturers add an acrylic finish to fiberglass to boost its durability.

As the name suggests, porcelain over steel is a bathtub material formed by coating a sheet of steel with porcelain enamel. These components combine to form a durable and affordable material with a smooth, glossy surface that’s easy to clean. But while the material is heavier than fiberglass, it has low heat retention and chips easily.

Acrylic is costlier than enameled steel and fiberglass but more durable. It can be used to create a myriad of designs in different colors. This bathtub material is formed by heating a mixture of materials until the desired product quality is achieved. The product is then molded into the bathtub shape and reinforced with fiberglass.

If you want a bathtub that will outlast you, get one made of cast iron. Cast iron is made by reducing iron ore in a blast furnace. Afterward, the liquid iron is poured and hardened into crude ingots. The ingots are remelted along with alloying elements and scrap metal in cupola furnaces and cast into molds for producing different products. While the material is expensive, it’s one of the most durable bathtub materials.

Cast polymer is an umbrella term that refers to the production of “synthetic” cast products like cultured marble, cultured onyx, and cultured granite. Recently, additional materials like engineered stone and acrylic resin-based materials have been added to the group. The casting process involves pouring a liquid resin into a mold, filling the cavity using gravity, and allowing the polymer to harden. Cast polymer molds are usually coated with a gel for aesthetics and to reduce porosity.

Ceramics are made by mixing clay, powders, earthen elements, and water. The mixtures are then shaped into desired forms and fired in a high-temperature oven (a kiln). Once they cool down, they are covered with glazes—decorative, waterproof, paint-like substances. Tubs made with the material are often used as accent pieces in old-fashioned bathrooms and are either made of smooth, glossy ceramic or covered with ceramic tile on their outer surfaces.

Stone is a superior choice compared to other materials. Stone bathtubs are made from natural stones like marble, onyx, sandstone, travertine, and granite. They are high-end and costly tubs that have a natural gorgeous appearance. Even without water, stone tubs are extremely heavy and need firm structural support. They also require more maintenance than other tubs.

Wood is rarely used to make bathtubs because the material is porous, and its pore structure greatly affects its behavior. You may have to custom-order a wood tub and be prepared to pay top dollar. Wood bathtubs are mostly made from African or Honduran teak, maple, ash, walnut, and cherry. A gel coating is then added for a glossy look.