the width of the eps portions 140 thereby inhibit sound travel along the surface of the panel especially but not limited to in a vertical sense fig2 a is a side view of a plurality of pre insulated structural building panels 100 configured to form a wall section 200 the wall section 200 may be arranged so that a tongue side 110 is mated with a groove side 120 of another panel 100 a fastening plate 160 may be used to fasten the plurality of panels 100 together fig3 a is an illustration of an embodiment of a wall section comprising a plurality of pre insulated structural building panels constructed according to principles of the invention the wall section generally denoted by reference numeral 300 the pre insulated structural building panels 305 310 comprising the wall section 300 are shown in two different lengths for example 4 foot panels and 8 foot panels arranged in a checkerboard fashion with a longer size panel 310 layered on top of a shorter panel 305 the pair shown in the left hand side of fig3 a and then the pair coupled laterally by tongue in groove mating as described previously with a second pair of panels the pair shown in the right hand side in fig3 a the second pair of panels includes a shorter panel 305 layered.