Bathtubs: Which material is the right one?
Classic oval pre-wall bathtubs, rustic wooden tubs or concrete bathtubs standing on a pedestal – there is a wide range of tub shapes and materials to choose from. Some materials require a lot of care, others are tough. It is important to make the right choice.
In view of the variety of shapes and styles for bathroom furnishings, the question of which material the new bathtub should be made of is sometimes pushed into the background by builders and modernisers. The differences between the individual materials are important. Not only the appearance of the tub is decisive, but also how it feels, how much it can withstand, how it is cared for and, of course, what it costs.
Material for the bathtub – past and present
From oversized clay jugs to wooden tubs: bathtubs have always been made of different materials – and mostly reserved for the ruling upper class. In the palaces of Mesopotamia, 2000 years before our time, bathtubs were made of clay. Those who wanted to bathe in medieval monasteries and castles climbed into large wooden tubs. In the 18th and 19th centuries, the era of modern bathtubs made of metal or porcelain began. Later cast iron was replaced by enamelled steel. From the 1970s, sanitary acrylic, a plastic material, made its way into the bathroom. The latest generation of bathtub materials are composites of synthetic materials with minerals. However, traditional materials such as natural stone, wood or cast iron bathtubs, as well as glass or concrete, are still popular for unusual or particularly luxurious bathroom furnishings.
Many builders and bathroom refurbishers first choose a bathtub shape and then a material. After all, most shapes are available in different materials. It should always be borne in mind that a free-standing bathtub is only effective in a larger bathroom with at least 15 square metres.
In the 1960s, the enamelled steel bathtub became the standard in the bathroom. It is still appreciated today because it is hard-wearing and durable.
Although steel is very stable and resilient, it can only be shaped to a limited extent, which restricts the design options. As protection against corrosion, the surface is coated with enamel, a fused glass made from natural raw materials such as quartz, feldspar, potash ash and metal oxides. The pore-free material of the bathtub retains its shine for a long time, repels dirt, bacteria or moulds, is insensitive to cosmetics and cleaning agents and does not discolour. The good practical and hygienic properties are countered by the disadvantage of the low heat storage capacity of steel enamel. The bathtub therefore feels rather cold and the bath water cools down more quickly. Even if enamelled bathtubs are scratch and abrasion resistant, the coating can flake off, for example if a hairspray can hits the enamel. Then the do-it-yourselfer must ran: By the damaged surface it can be that the steel begins to rust under the coating.
The first sanitary acrylic bathtubs were launched in the early 1970s. It is a thermoplastic, i.e. plastic that can be shaped under the influence of heat. To produce a bathtub, the material is heated to approximately 180 degrees Celsius in the form of a plate and pressed into an aluminium mould. After cooling, the tub is reinforced with acrylic, wood and glass fibre fabric on the underside to increase stability.
The good formability of the material opened up new possibilities for bathtub design. Sanitary acrylic is also lighter than steel enamel and stores heat better. The pore-free surface is smooth but non-slip, break-proof, impact and shock resistant. However, bathtubs made of sanitary acrylic are sensitive to scratches.
Composite materials based on acrylic or polyester resin
A more recent development is bathtubs made of composite materials based on acrylic or synthetic resin mixed with minerals. The materials are therefore also referred to as solid surface materials or mineral castings. What they all have in common is that they are very strong, but very easy to form and process.
All mineral materials are resistant, easy to clean and feel warm like sanitary acrylic. The fact that they can be shaped at will makes them the ideal material for designer bathtubs in the upper price range.
Old material, rediscovered: Wooden bathtubs are once again enjoying great popularity. In addition to the traditional rustic wash tub look, there are also models in modern shapes. Due to the good heat storage, the wooden bathtub feels pleasantly warm. A durable and elastic sealing of the bathtubs, which constitutes the quality difference, is important. Nevertheless, a wooden tub needs to be well cared for. Interested parties should look out for tubs made of resin-rich trees such as larch or teak.
Its transparency and smooth surface make glass bathtubs look very elegant. The fragile material is surprisingly robust: glass has high impact resistance and is insensitive to water, acids and alkalis. As a bathtub it is also very suitable in combination with other materials such as acrylic or wood.
Natural stone: marble, travertine & Co.
A bathtub made of marble, travertine or onyx is the epitome of luxury – which costs accordingly. But every bathtub is unique, because no stone is like another. Natural stone is very robust against mechanical stress and absorbs heat well and for a long time. Marble and Co. are however quite acid-sensitive. It should also be remembered that natural stone tubs weigh a lot and are therefore usually not suitable for upper floors. At the very least, the load-bearing capacity of the floor should be checked before installation.
Advantages and disadvantages of the most common bathtub materials
Actually, basic bathroom equipment is not so expensive. In its simplest form, builders and renovators pay around 2,000 euros for washbasins, toilets and bathtubs. However, only the simplest version and the cheapest material are used. The price driver for sanitary ceramics is certainly the bathtub: special materials, unusual bathtub shapes and specific connections mean that the price rises significantly. Who would like to furnish its bathroom again or reorganize, should be conscious of it.
The table summarises advantages and disadvantages and gives a rough price overview.
|Steel Enamel||Resistant And Durable Dirt-repellent Recyclable||Low Heat Storage, Feels Cold At More Expensive Than Sanitary Acrylic||120 – 5,000 Euros|
|Sanitary Acrylic||Resistant To Impact And Impact Resistant To Breakage Low Mounting Weight Non-slip Surface Chemical-resistant Easy-to-clean Recyclable Good Heat Storage||Sensitive To Scratches||150 – 7,000 Euros|
|Mineral Materials Such As Corian, Quaryl, Cristalplant, Ceramilux||Warm Feeling Hard And Resistant Pore-free And Easily Diverse Malleable||Comparatively Expensive||2,500 – 6,500 Euros|
|Natural Stone||Durable, Robust Unique||Hardly Sensitive To Chemicals||30,000 – 50,000 Euros|
|Glass||Slightly Resistant||Easily Deposits Of Lime Or Body Care Products||With Glass Insert From 2,000 Euros|
|Wood||Natural Material Good Heat Storage No Disposal Problems||Inexpensive Models Have Partly Inferior Seal||800 – 30,000 Euros|
|Concrete||Individually Moldable Durable With Sealing Easy To Clean||Heavy Expensive Custom-made||As Concrete Pans Can Be Cast Individually, Prices Are Only Available On Request From The Manufacturer.|
|Cast Iron||Stable Resistant||Feels Rather Cold On Hard Expensive||3,000 – 13,000 Eu|