1.  Field of the Invention
This invention relates to a building.  More particularly, the invention relates to a building suitable for use in mass-housing.  The invention extends to panels for use as the structural elements of the building and further to a method of constructing the building. 
2.  Description of the Prior Art
Conventional buildings used for low-cost mass-housing are still relatively expensive mainly due to the type of structure employed which necessitates long construction periods and usually the employment of skilled labour.  The basic structure of some types of houses employs bricks and mortar which houses are inevitably relatively expensive to build due to the high labour input needed.  Other houses mainly employ pre-fabricated structural elements which can pose transport problems due to the mass and volume of these elements and the lack of stackability.  Further, the conventional houses pose thermal shortcomings and lend themselves only in a limited way for aesthetic and ecological inter-action with the environment and the inhabitants.  In the aforementioned context one can typically refer to houses erected in squatter camps.  It will be appreciated that urbanisation and adverse economic conditions presently lead to a growing squatter problem which consequently, of course, has an extremely negative effect on the environment and the inhabitants themselves.  A further shortcoming of most conventional houses used for mass-housing is the lack of extending and upgrading especially the lack of providing thermal insulation on the outsides thereof. 
Internationally, more than half of the world population is without adequate shelter.  Various governments annually spend billions of dollars to alleviate the housing problem, but with limited success, mainly due to the problems, mentioned above, of transport, construction and further of supervision.  The long construction periods create further backlogs which result in further social and economic delay. 
The applicant is aware of the following patents showing various forms of buildings:
German Patent No.  DT 2950-719, Dec. 18, 1978 to Schlather F. discloses a building composed of corrugated sections supported by an extra timber structure which is essential to this building.  Disadvantages of this building thus include the vast number of components necessary to construct it which makes this building less suitable for mass-housing as longer construction periods are needed.  Further, cavities in the structure are needed for filling with polystyrene granules as insulation material.  Also a special type of foundation is needed, that is, comprising an aerated concrete with polystyrene granules thus further adding to the cost of this building.  PA0 French Patent No.  2 529 928, Jul. 9, 1982 to Chazal P. discloses a compact, trapezoidal structure consisting of seven panels which generally form a tunnel which is non-optimal for solar heating as only the two sloping walls of the four walls can be used for solar heating.  The respective panels are articulately attached to each other for packing and transport purposes.  A disadvantage of this building includes the complexity of the plurality of attachments which will render this building relatively expensive.  PA0 Great Britian Patent No.  1 330 508 to Universal Papertech Corp, Oct. 19, 1970 discloses a pre-fabricated building with also only two sloping walls which building has a general tunnel shape as mentioned above, and only the two sloping walls of the four walls can be used for solar heating.  This building too is constructed of a vast number of components and insulation is attempted by filling the cavity walls with an insulating material.  Insulation here is attempted from the inside of the building.  PA0 U.S. Pat.  No.  4,285,174 to Knight B. V. Aug. 25, 1981 discloses a free-standing building with trapezoidal-shaped panelling.  This building is especially designed for bulk storage of materials and not for human occupation.  Apart from the aforementioned limitation the profile of the walls does not enhance the use of insulation material and is non-optimal for solar heating.  PA0 U.S. Pat.  No.  4,365,453 to Lowe F. L., Dec. 28, 1982 discloses a frameless metal building with corrugated rectangular panelling.  A crane is, however, needed for ease of construction thus increasing cost of construction.  The shape of the panels is further non-optimal for solar heating.  Insulation may possibly be accomplished for which cavities in the structure are needed.  A further disadvantage of this building is the excessive thermal bridging between the inner and outer wall panels. 
A general shortcoming of the abovementioned prior art buildings is the lack of providing a basic unit which can be upgraded in a simple way, for example, by providing thermal insulation on the outside surfaces.  The prior art buildings which can be insulated essentially need cavities to be filled by material, for example, granules.  A further shortcoming of the prior art buildings is the lack of expanding the building to provide a multi-building.  Another shortcoming is the lack of stackability of the various components employed. 
There accordingly exists a need for a relatively inexpensive, environment-friendly building which can be used in mass-housing projects and which building can be thermally upgraded in a simple manner and further expanded.  A further need exists for stackable panels readily transportable, the panels for use in the construction of the building.