A support system for supporting a floor relative to an underlying surface, said system comprising a panel stringer made of thin metal plate and having a generally inverted U-shaped cross-section profile with two generally parallel side portions (16, 18) and a generally planar interconnecting portion defining a supporting surface, a plurality of spaced apart through-going apertures being provided in said interconnecting portion, a first plurality of supporting elements, adapted to support said panel stringer, each supporting element comprising a vertical through-going bore defining an interior screw thread, each of said supporting elements being slidably positionable along said panel stringer within said inverted U-shaped cross-section profile for positioning a specific supporting element in registration with a cooperating specific aperture of said plurality of spaced apart through-going apertures, said specific supporting element supporting said panel stringer and cooperating with said panel stringer to prevent rotation of said specific supporting element relative to said panel stringer, and, a second plurality of elongate supporting legs made of a cutable material and adapted to support said supporting elements, each supporting leg being generally cylindrical and having a diameter adapted to allow it to pass through said plurality of spaced apart through-going apertures of said panel stringer and each supporting leg further having an exterior screw thread interengageable with said interior screw thread of said supporting elements and an inner recess provided at one end constituting a top end and defining a tool engageable part for engaging with a tool and an opposite bottom end serving to engage with said underlying surface. a panel stringer made of thin metal plate and having a generally inverted U-shaped cross-section profile with two generally parallel side portions (16, 18) and a generally planar interconnecting portion defining a supporting surface, a plurality of spaced apart through-going apertures being provided in said interconnecting portion, a first plurality of supporting elements, adapted to support said panel stringer, each supporting element comprising a vertical through-going bore defining an interior screw thread, each of said supporting elements being slidably positionable along said panel stringer within said inverted U-shaped cross-section profile for positioning a specific supporting element in registration with a cooperating specific aperture of said plurality of spaced apart through-going apertures, said specific supporting element supporting said panel stringer and cooperating with said panel stringer to prevent rotation of said specific supporting element relative to said panel stringer, and, a second plurality of elongate supporting legs made of a cutable material and adapted to support said supporting elements, each supporting leg being generally cylindrical and having a diameter adapted to allow it to pass through said plurality of spaced apart through-going apertures of said panel stringer and each supporting leg further having an exterior screw thread interengageable with said interior screw thread of said supporting elements and an inner recess provided at one end constituting a top end and defining a tool engageable part for engaging with a tool and an opposite bottom end serving to engage with said underlying surface.