Abstract: A sleeper is disclosed comprising a guideway, a resilient strip, a nailing bed and a spring. The guideway is an elongated channel of C-shaped cross-section with three fully closed faces and a partially open face. A plurality of the guideways are fastened to the floor base and the resilient strips placed in the bottom of the guideways. The nailing bed is an elongated wooden element with an elongated protrusion. The nailing bed defines an inverted T-shaped cross-section and is placed in each guideway above the resilient strip. The protrusion of the nailing bed extends through the partially open face for attachment to the flooring material. The nailing bed is shorter than the guideway to leave sufficient room within the guideway at at least one end of the guideway for the spring. The spring is inserted with one end against the end of the nailing bed. The spring is then compressed and a stop inserted through the guideway to maintain the spring in the compressed condition.