It should be quite possible to convert drawing saved in DXF format (.dxf) to plenty of other 3D model formats, including special BIM formats, such as Industry Foundation Classes files (.ifc). This can be mainly done with tools that deal with architecture and building modeling, for example FreeCAD.
Open DXF file Open IFC fileAn open source multiplatform 3D CAD/MCAD/CAx/CAE/PLM modeler