A new fabrication and stiffening method of SRF cavities is proposed. The principle is to spray a copper layer onto a thin wall niobium cavity. The main advantages of this technique are fabrication cost re- duction and stiffening method simplification. Numerical simulations were performed to demonstrate the efficiency of the proposed stiffening scheme on the reduction of the cavity frequency shift due to Lorentz forces. A first series of cavities (3 GHz) were fabricated and the corresponding cold RF tests are presented. Finally, the overall thermal re- sistance of different samples was measured and the results are discussed.