Low Cost Housing

Affordable Housing - a Concept to Combat the Shortage of Housing in Crisis Areas

The Low Cost House concept is the solution for rapidly growing and poor sections of the population who need high-quality living space. Solid concrete houses for the accommodation of people in need can be made available in a short period of time. This is made possible with the Butterfly Battery production technology developed by BT innovation. A formwork system for the fast and efficient production of precast concrete elements.

The Low Cost House concept is an ideal solution for governments and aid agencies that are confronted with large numbers of refugees in crisis areas or need safe accommodation for the population after natural disasters. With the Low Cost House, the creation of safe, stable and cost-effective living and utility space can be achieved in only two hours.


  • Solid concrete house
  • Set-up time: 2 hours
  • (nearly) location independent production
  • Industrial large scale production
  • Standardized technology
  • Short period of adjustment


The Low Cost House concept at a glance

The construction of a turnkey concrete house of 36 m² with two bedrooms, living area, kitchen, and bathroom can be completed in only two hours. This is made possible with the simple building concept of BT innovation.

In this video you can follow the first construction test ever which only took two hours for the successful implementation.


Service range (Standard)
  • 36m² base area
  • Four rooms incl. bathroom with shower and toilet
  • Room for 4-8 people
  • Outlets, light switch
  • Water connection in bathroom and kitchen

The production of the precast concrete elements for a Low Cost House is executed with the Butterfly Battery Formwork developed by BT innovation.

The production mould has the following advantages compared to conventional technologies:

  • The production process is faster and simpler
  • High productivity with relatively small base area
  • The surfaces are five-sided formwork smooth, no further finishing of the elements is required

The key to success in implementing the Low Cost House project lies within our technical know-how and the technical equipment itself. With the professional guidance of BT innovation, local workers will learn to handle the equipment. For this purpose, they will be instructed and trained in the production of concrete elements and the assembly of prefabricated houses. In this way, jobs are created in the target regions, regional value chains are strengthened and project acceptance improved.

You can find more technical information about our Butterfly Battery HERE.

The prefabricated elements should be designed in a way that an extremely high degree of prefabrication can be achieved. Preferably, the individual concrete elements are prepared to such an extent that a house is ready for occupation immediately after the individual parts have been assembled and no or only minor finishing work is required. For this purpose, it is intended that:

  • Walls, ceilings, and roof areas will be provided with complete surface processing, inside and outside. With the use of colour pigments, additives, or special formulations, finishing work like plastering, painting, tiling, or wallpapering will be avoided.
  • The basic installations for electricity, water, and sewage systems are already included in the wall components. These just need to be connected to the relevant networks when assembling the house (if available).
  • Water and sewage tanks will already be considered in the building design for the target region’s usual supply.

In particular, alternative and sustainable supply possibilities can also be considered, such as:

  • A roof drainage system that collects rain water and directs it to the appropriate tanks for later use as drinking or service water.
  • An energetic supply of the house via solar energy, which can later be used for electricity, heating and cooling purposes.


In general, BT innovation is able to adjust the production to the customer’s requirements. The standard Low Cost Hose concept is offered with a base area of 36 m².






Depending on the region and demand, different roof types can be implemented. On the one hand there is the flat roof version (standard) on the other hand there is the classic saddle roof version. With a flat roof, multi-storey arrangements with external stairs or semi-detached houses can be implemented.

In order to achieve the very short construction times in low cost housing of only 2 hours, so called “dry” joining techniques is used. For this, the BT-Spanschloss® (turnbuckle) developed by B.T. innovation GmbH is well suited. It allows the simple and precise connection of the individual pre-cast concrete components and makes it possible to construct the low cost house in just two hours! No tools are needed to connect the components. This saves a lot of time and money. After construction, the BT-Spannschloss® is immediately fully weight bearing and remains so for the long term. The BT-Spannschloss® has been certified as approved for general construction by the German Institute for Structural Engineering. (DiBt – Deutsches Institut für Bautechnik).


To protect the house from water, dust and insects, we recommend the RubberElast® joint tape developed for dry connections. It is very easy to use and can be applied at almost every temperature. The material is securely bonded to the concrete elements by the contact pressure and remains permanently elastic. RubberElast® fulfills high quality standards and is therefore certified by the German Civil Engineering Materials Testing Institute.

Our sealant and waterproofing portfolio is complemented by the flexible InnoElast®. It seals expansion and connection joints reliably and permanently, both indoors and outdoors and is certified by the German Materials Testing Office North Rhine Westphalia.

Transport of the building components can be carried out using a shipping pallet modified by B.T. for instance. It is possible to transport all the components of the house on this pallet. The advantage of this technology is that the load of components can be carried directly on the alternating system of the load carrier. This means that costly transshipment and expensive standing times for trucks can be avoided.


The houses are basically built of concrete. Concrete is one of the most frequently used building materials in the world and can therefore be produced almost anywhere to a reasonable grade with raw materials that are available locally. It is easy to work with and can be formed into virtually any shape. Concrete has sufficiently good physical properties for building; it is very robust and therefore perfectly well-suited for constructing solid durable buildings.