The Karanttia® modular bathroom is delivered to the construction site completely ready and equipped with all bathroom furniture and fittings. Owing to its excellent durability, the concrete modular bathroom can be used in many stages of life; it contributes to the building’s life cycle, since aids, for example, can be easily moved and added to any locations, for the wall structure will endure this without problems. Karanttia® modular bathrooms bring relief to developers, designers, and contractors alike. Customer customization works can be integrated into our preliminary design and manufacturing process. Karanttia modular bathrooms are manufactured by Rakennusbetoni- ja Elementti Oy.


Karanttia® modular bathroom are delivered to the work site completely ready, with all the furniture and fittings. The installation takes 15-20 minutes. Our design and production process allows customized solutions and modification flexibility.

  • Made from concrete, very resistant to moisture and service.
  • Facilitates design and construction works.
  • Promotes cost and work site process predictability.
  • Reduces the volume of work site operations and repairs.
  • Accelerates the building project.
  • Easy and quick to connect to building services.
  • Shorter on-site construction time.
  • The construction of the module, its moisture insulation and furnishing take place in controlled dry indoor environment.
  • Ensured compliance with quality, accessibility, and regulatory requirements.
  • A single supplier has the overall liability.


Our design services produce ready-to-use architectural, HVAC, and structural drawings in the form preferred by the customer within the limits of the design and construction period. We can tailor the bathroom to the customer’s and site’s wishes. Our typical bathroom design images are compiled into a single file.

Contact us for downloadable images for your convenience.

The file includes:

  • DWG images
  • 3D models
  • Design instructions
  • Installation instructions
  • Brochure


Seinäjoen Tuohi

Asunto Oy Seinäjoen Tuohi is the first building constructed on the basis of the Sydänpuu concept developed by Lakea. Karanttia modular bathrooms were supplied for the site.


Kumpula, Helsinki

Sato built a handsome 5-storey building on the Gadolininkatu Street, on a hill ridge near the Kumpula Campus. There are SATO rental homes for many life situations in the building, from compact studios to spacious apartments. Karanttia modular bathrooms were supplied for the building.

A Karanttia® modular bathroom is an innovative ready-to-use product made of concrete and delivered to the work site fully completed.

The bathroom prefabricated at the factory comes with all the necessary furniture and fittings. Owing to its excellent durability, the concrete modular bathroom is adaptable to all life cycle stages, since aids can be moved and added to any locations without problems owing to the durable wall structure. The modular product can also be easily converted, for example, from a bathroom originally intended for a student’s apartment into a bathroom for the home of an elderly person.

The industrially prefabricated bathroom speeds up the work site construction process and improves building project predictability. Our design service allows customer-oriented and customized solutions. Concrete as the bathroom construction material ensures uniform quality, prefabrication improves building project cost management, since unforeseen costs are avoided. The use of a prefabricated concrete modular bathroom is predictable, classy, and responsible. Bathroom implementation issues have been resolved already in the design stage, which brings efficiency and added value to the construction site and throughout the construction supply chain.

If modular bathrooms are used, the site must be designed from the start with prefabrication in mind, in order to ensure the schedule and productivity benefits granted by prefabricated complete solutions. For the duration of the design stage, Karanttia’s design team is at the building project’s disposal. The design team consists of an architect, HVAC and electrical designers, and a structural designer. Utilisation of prefabricated bathroom modules in buildings requires co-operation between specialised designers and operators during the design stage.