NOVELTY - Preparing (M1) reaction product comprising silane product involves contacting organohalide with calcium silicide at 300-700 degrees C to form reaction product comprising spent reactant and silane product of formula RmHnSiX(4-m-n); contacting spent reactant with silane of formula HaRbSiX(4-a-b) at 200-1400 degrees C, and contacting spent reactant with H2 for forming reactant; contacting the reactant with additional organohalide at 300-700 degrees C to form additional silane product of formula RmHnSiX(4-m-n); and recovering the silane product.    USE - For preparing reaction product comprising silane product such as hydridotrihalosilane useful as reactant in chemical vapor deposition process for making polycrystalline silicon, or in hydrolysis process to produce polysiloxane; tetrahalosilane useful as reactant to make hydridohalosilane and/or organohalosilane; diorganodihalosilane useful as reactant in hydrolysis process to produce polyorganosiloxane; organohydridohalosilane useful as reactant to make polyorganohydridosiloxane; and tetraorganosilane useful as a reactant in chemical vapor deposition process (claimed). The polycrystalline silicon is used in solar cells (solar grade polysilicon) or electronic chips (semiconductor grade polysilicon). The polysiloxanes is used as resins. The polyorganohydridosiloxanes is useful as waterproofing agents.    ADVANTAGE - The method is economical and avoids use of zero-valent silicon.    DETAILED DESCRIPTION - Preparing (M1) a reaction product comprising a silane product involves: i) contacting an organohalide with a calcium silicide at 300-700 degrees C to form the reaction product comprising a spent reactant and the silane product of formula RmHnSiX(4-m-n), where the method further involves steps (ii) and (iii) which are performed separately and consecutively after step (i); ii) contacting, at 200-1400 degrees C, the spent reactant with silane of formula HaRbSiX(4-a-b), and contacting the spent reactant with H2 for forming a reactant; iii) contacting the reactant formed in step (ii) with additional organohalide at 300-700 degrees C to form additional silane product of formula RmHnSiX(4-m-n); iv) repeating steps (ii) and (iii) at least one time to form further additional silane product of formula RmHnSiX(4-m-n); and v) recovering the silane product after step (i), (iii) and/or (iv).    R=monovalent organic group;    X=halo;    m=0-4;    n=0-2;    m+n=0-4;    a=0-4;    b=0 or 1;    a+b= less than or equal to 4.    Provided that the silane of formula HaRbSiX(4-a-b) is distinct from the silane product of formula RmHnSiX(4-m-n), and that when the quantity (a+b) is less than 4.