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Utility model for hemp sauna – Lehtinen entrepreneur brothers invent as much as they have time from their work


June 27, 2019

Erikoistyöt Lehtinen Oy from Kokkola has decided to make the most of both sauna bathing and the protection of their latest sauna invention. The hemp sauna developed by the entrepreneur brothers Ari and Jari Lehtinen was recently granted a utility model. Kolster serves as a sauna buddy in the protection.

“Sauna bathing with Ville Haapasalo”

The entrepreneur brothers Ari and Jari Lehtinen from Kokkola never run out of ideas – and they are usually born in the sauna.

“We both like sauna bathing, and there is time to talk and plan all kinds of things while sitting in the sauna. New ideas arise easily as you throw water on the stones. Last winter, the idea of a hemp sauna was born”, the brothers say. 

Inventions are created at such a speed that there is not always even time to protect them before they “slip out” and become public. That is what happened to the brothers’ first two sauna inventions, the diving sauna and the aquarium sauna. The prototypes immediately aroused so much interest that it was not long before the passionate sauna enthusiast and media personality Ville Haapasalo sat in the sauna under water with the brothers with the whole country watching it on the TV programme Haapasalon Suomi.

The brothers were vigilant about protecting their third sauna invention, the hemp sauna. Ari Lehtinen contacted Kolster’s patent attorney Håkan Niemi, who was already a familiar face, right at the early stages of the invention.

“Our cooperation with Håkan started back in 2007 when we protected a roller conveyor invention with a utility model. The conveyor facilitates the loading and unloading of cumbersome loads to and from a trailer. I said already at that time that the guy is in the right industry. I appreciate Håkan’s hard-core professional expertise and good humour”, Ari Lehtinen says.

“We wanted a healthy and breathable sauna”

As its name suggests, Erikoistyöt Lehtinen performs a wide range of cleaning, demolition and repair work requiring special expertise and equipment, such as special blasting, steam deicing, pressure cleaning, odour control and plastic welding for industrial companies and private customers alike. Special blasting work is currently at the core of the business – and who knows, perhaps special saunas will be included in it too in the future?

The brothers provided their comments for this story from a site where they were blasting away mould using a dry ice method from a building suffering from water damage. The next project is at an industrial company where they will clean tanks and also handle their repainting. Mouldy wooden structures, rusty metals and dirty plastic materials are everyday work. To counterbalance this, an idea of sauna building materials that are as natural as possible and a new way to build a mould-free, chemical-free and breathable sauna took shape. 

Hemp is an ancient Finnish natural material that was once a familiar filling in traditional log construction: it is a very strong and wet-proof building insulation material.

“From the point of view of protection, the unique thing about the hemp sauna is the grid-like double structure of its walls. It is as though the structure has two circles built from sparsely spaced pieces of wood and an empty circle in the middle with hemp insulation. In addition, all the spaces between the pieces of wood have been filled with hemp”, Ari Lehtinen describes the technical solution of the hemp sauna.

Hamppusauna - rakennuskuva - Erikoistyöt Lehtinen

“The mild heat of the hemp sauna will not tire you out”

According to Lehtinen, the hemp sauna differs from the traditional sauna the most in that bathers will not be tired out or feel ill there. The heat is mild and will not bounce back with a vengeance, like it does from the walls of wood-panelled saunas. The grid structure allows the building to breathe from two sides. You will not run out of air there. The roof structure also has hemp insulation and the roof is made of shingles.

“We have used bathers who get tired easily in a normal sauna and cannot stay there for a long time as test persons. In the hemp sauna, even these bathers have been able to feel comfortable for up to two hours. The sign of a good sauna is that you can stay there for a long time and bathing is pleasant for the whole duration.”

The wall structure is cross-ventilated but insulates enough heat. The walls are built of pieces of wood; in practice, waste from other wood construction.

“Despite the breathable structure, the hemp sauna offers very nice heat for bathing. The fresh aroma of the hemp plant is a pleasant bonus.”

There are already ideas for further development.

“Hemp is visible outside the building as well, and it is also favoured by birds for building a nest. This problem will be eliminated if we cover the entire sauna with shingles. That will also give it a cool look. We may also put the sauna on pontoons to have it afloat”, Ari Lehtinen envisages.

Sukellussaunan prototyyppi_Erikoistyöt Lehtinen

The diving sauna prototype weighs around 6,000 kilos: a lighter structure would not stay under the surface. The sauna is entered from an opening on top, and the oxygen for the fire in the stove comes through an air pipe. There is a grandstand view of life underwater through the large, round front window. The sauna dives the structure remains on the surface.

Sukellussauna_Erikoistyöt Lehtinen

Akvaariosaunan prototyypin ikkuna - Erikoistyot Lehtinen

Ari Lehtinen presents the window view of the aquarium sauna prototype from inside to the pool. The sauna is within a glass pool that is two metres deep and filled with water. The bather and friends are like aquarium fish.

“New Finnish sauna brands under development”

According to Ari Lehtinen, the technical solutions of the diving and aquarium saunas would absolutely have been equally worth protecting as those of the hemp sauna, but the brothers have not been left lamenting over the lack of patent or utility model protection. They already have new protection plans in mind: sauna brands of the future.

“Protecting product names is not even expensive. We will register trademarks for all the saunas if and when we start manufacturing them for sale. We have not come up with suitable product names yet, but their registration will be considered as soon as we get a little bit further with things.”

A further development, finished product version of the aquarium sauna prototype is already in the making. You are sure to hear more about the Lehtinen brothers’ special saunas.

“With our other work, we have not yet had time to do much else than to sort out production matters a little and go to sauna. We will be bathing in the hemp sauna on Midsummer. Then we will look at how this organic sauna could first be introduced more widely to be enjoyed by others as well.”

“The most important things in cooperation are honesty and easy communication”

Ari Lehtinen explains that, for a small entrepreneur, he is quite well versed in patenting and other forms of protection, even though everything has not always gone quite by the book in his own company.

”I have studied protection issues quite a lot. The difficulty of patenting lies in what can and should be protected and in which countries, as you cannot possibly take out a patent everywhere. A utility model is a good protection for technical solutions for a small company even in terms of cost.”

The hemp sauna is now protected for ten years, i.e. until 2029, with a utility model. It provides protection against direct product copying.

“The strength of the protection is very much influenced by how the documents are written. Håkan was able to get a good grasp of this invention right away. He carefully considered the wording so that we will benefit from the protection if we can push our sauna to a bigger market”, Ari Lehtinen says.

According to Lehtinen, straightforward communication has been very important, as well as the fact that things have been resolved swiftly.

“I also appreciate things being told frankly and honestly. It has been nice and easy to work with Håkan. He has been involved in our inventions in spirit, a bit like a business partner.”

What unique things to protect does your company have?