This was our second boat,an 18ft cabin cruiser,that was double skinned although the floor had been removed when we got her ,so we fiitted a two piece marine ply floor,sold the first boat to pay for a big engine the first was a bit noisy,sold it and bought a 60hp yamaha fast but stable as it has adory hull that's like one bid V in the middle and two smaller V's at the outside, the only down side was in biggish waves it was noisy,as the water slapped in between the hulls.