Patent ID: 8499526

Claim:
A method of forming, at a building site, a stable and, in terms of weight, heavy modular unit that can be adapted to serve as a complete modular-built cellar unit, the method comprising the steps of: transporting to the building site a prefabricated and, in terms of weight, considerably lighter complete modular unit previously formed at a production site different from the building site, said lighter modular unit including: a base slab having length and width dimensions corresponding to those of a cellar, a plurality of double-walled wall sections formed from flexurally rigid cement fiber panels and anchored to the base slab, the plurality of double-walled wall sections including a number of inner wall portions facing in towards the modular unit and a number of outer wall portions facing from the modular unit, said inner and outer wall portions being mutually coordinated, a plurality of supports securing said inner and outer wall portions together, the plurality of supports being located within a free space formed between the inner and outer wall portions, and dimensionally defined by said inner and outer wall portions secured to one another via said supports, and one or more modular unit-allocated interior design details mounted within the double-walled wall sections, at the building site, filling the free space with a concrete mass which is caused to cure or set to form, in terms of weight, in combination with the lighter modular unit., the heavy modular unit, the inner wall portions having such dimensions and mechanical strength-related properties that these inner wall portions, in combination with only said supports, support selected ones of the modular unit-allocated interior design details, which are fixed to selected wall sections of the inner wall portions, and form a first form side of said free space that is able to withstand the pressure forces occurring upon concrete pouring into said free space, and said outer wall portions having such dimensions and mechanical strength-related properties that these outer wall portions, in combination with only said supports, form a second opposing form side of said free space that is able to withstand the pressure forces occurring upon concrete pouring into said free space.