A Wooden Bathtub - that is something completely new on the market, right?


Old style wooden bathtubDid you know that wooden bathtubs have been used since the Middle Ages? These tubs were held together by metal straps on the sides to withstand the water pressure. Today, many centuries later, there are still several manufacturers who specialize in this technology. Another possibility is the usage of multiple layers of veneer which are glued with large amounts of synthetic resin into forms. The opinions in this process vary. There are people who have no problem with a wooden tub, which consists largely of artificial material. This is exactly what is in fact the case with these saturated products. Not to mention that the requirement of an mold makes it nearly impossible to individualize the size and design.

We at grinERA deal with a further opportunity to produce elegant wooden bathtubs. We avoid the metal stripes and also laminated veneers. Here you will find only solid wood products.

A wooden bathtub from grinERA is made from such wood


We merge solid wood elements accurately and overlapped to each other using high-grade glue. This design is many times more complicated than a typical "hot tub" design, or a laminated bathtub. However, this technique offers enormous advantages for a bath. Our bathtubs have a wall thickness of 5cm - 8cm from pure and solid wood. Because wood is a very good heat insulator, you can save energy. The bath water does not cool as quickly, but stays warm much longer than for example in a metal, acrylic or laminated bathtub. In addition, we can change the shape of every bathtub based to customer wishes.

The production process of our wood bathtubs in detail:

Before we can start with the production of a bath,  first there is the question of what type of wood should be used. In the past, mostly woods such as larch, kambala /iroko, and teak were used, which have naturally a strong resistance to water. For several years now, more and more companies also use other types of wood for sanitary products.

The inside of this bathtub is grinded - The outside still needs a lot of work Technological advances in impregnations, coatings, and mixtures of natural oils have made quantum leaps, and allow us now to use a large variety of woods for bath products. We have many years of experience with several tests performed through the years to have the certainty that our products will withstand the rough conditions they are being designed for - resistance to water.

Whether straight, round, or in combination. grinERA uses modern woodworking machinery, and innovative self-developments to obtain a perfect result. Our round wooden tubs for example, are being put together from more than 100 precisely sawed parts. Every layer of wood is glued over each other and differ in diameter and wall thickness. On the computer the required elements are calculated so that in the end everything fits. The raw structure already stands after the gluing process. Now comes the next part which consists of milling and grinding of the base, the inside and the outside, in order to obtain a smooth and shiny  wooden bathtub.

The ouside is also finished. Now we add the hole for the waste and the coating


The loud and dusty wood processing is completed with the already described section. Currently, about 50% - 70% of the wood planks have been processed to sawdust and firewood. There remains a jewel that has reached its final shape, which will probably also delight the grandchildren of the new owner, once the next step is completed.

Now follows the time-intensive surface treatment in which you can choose between our multi-layer coating and our ecologic natural oiled surface.

 

Multi-layer coating


1. Impregnation

After the wood processing is complete and the entire surface was uniformly abraded by hand, we begin with the surface treatment. Our very deep penetration of impregnation is the basis for a long-standing resistance to the water. hand polished surface of our multi-coated bathtubsWe work with different consistencies. First, the impregnating liquid is extremely thin. This ensures that the impregnation penetrates much deeper into the wood, as even water would be able to. Our impregnation liquid binds deep inside with the cells of the wood. We repeat this process with different mixtures, until the wood is saturated (no longer acts like a sponge) and thus provide a basis for the further layers.

2. Primer

After the deep-acting impregnation is complete, we start with the next step.

The aim of priming is the highest possible connection between the wood surface and the coating. Surely you have  seen in other areas burst paint layers, which can result from an incorrect surface structure.  Most of this damage resulted from improper paint, or their construction of layers. Each timber expert will tell you that wood is a natural product, which will always work a bit in one or another direction. The used coatings should take this into account, and contain a certain amount of flexibility. Our primer will help at this very spot. and forms the correct intermediate layer. The undercoat is water resistant, binds extremely strong to the wood surface and provides the right basis for further steps. We use several layers of primer and smooth-grind the entire surface between the layers to achieve a perfect result of the primer.

3. The final touch: UV and scratch protection

The already-described layers took about two to three weeks. After each layer, we let the bathtub dry out completely, before it goes to the grinding and the next layer. Too fast work reduces the quality, which has the highest priority for us.

The wooden bathtub is almost ready to be sent to the customer, and is already completely waterproof - but there is another aspect to consider. The wooden bathtub is supposed to stay shiny for many years. That's why the tub receives several layers of our special coating at the end. This coating, which consists of various components will be polished by hand and subsequently results in the high end surface that you want for a wooden tub. The surface is similar to that of a car and can be polish again after some years. Scratches caused by improper cleaning (abrasive), or by accidents, such as fallen perfume bottles can therefore be easily removed, so that the tub looks like new again.

Oiled surface


With a few exceptions to the wood selection  all of our products can be also made with a completely natural surface.
We use the following layer structure:
Our oiled surface contains a mixture of different oils. These include Tung oil (also known as Chinese oil) and linseed oil. Tung oil has been used for centuries for waterproofing. Did you know that the Chinese wall was preserved with this oil? oiled surfaceIn a particular order, various mixtures are stirred, the first of these are very thin and thus penetrate deeply into the wood. The so-called polymerization of these particular oils results with a advantage to other oils. This chemical reaction occurs by irradiation with UV light and oxidation. The oxygen in the ambient air reacts with the mixture and causes a strong hardening. A major advantage of our method is that the oil expands during its cure (The situation is similar with water when it freezes). Thus, even the smallest air pockets in the pores of the wood is filled and sealed, leaving no attacking spot for water.
We repeat this process several times, until the wood is completely saturated. Between each new layer we must first wait for the previous one to dry out. This is the only way to ensure that the desired result - a fully waterproof surface that is waterproof for decades - is being achieved.
After the wood is completely impregnated, we deal with the surface. Another similar mixture of oils and other additives, helps to achieve a durable surface. This mixture we also add to our products, when they are being sent to you. It is recommended to cover the entire surface  occasionally (1-3 times annually) and remove excess oil. After each procedure, you'll see how the grain is getting a deeper texture.
Scratches caused by improper cleaning (abrasive) or by sharp objects such as bottles of perfume or rings, can be grinded with fine sandpaper without complications. After the grinding, one or two coats (let dry out between layers) are applied  and can be polished in the end.

The tub is now ready and can  get on its way to the customer. The wooden bathtub will be securely packed on a pallet or in a huge wooden box packed for the trip to other continents. We can reach each destination worldwide, working with great shipping partners together.

Whether you decide for a oiled surface, multi-layer coating - whether tub with metal straps, made from laminated veneer or solid wood. The choice is yours. We hope the information on this website can help you to make the right choice for you. If you still have questions, please do not hesitate to contact us. We are happy to discuss further questions with you. Here you can be certain, that your expectations of a  high quality  and long lasting product from a German company will be met.