There is a method for producing a ply involved in the construction of a multi-ply panel for constructing or adding to a wall, floor or ceiling, or a sloping part for a building. The ply includes a juxtaposition of strips, either structural strips or filling strips, positioned between the structural strips and made of a different material from that of the structural strips. The materials are selected for the thermal or acoustic insulation thereof, the thermal inertia thereof or the fire résistance thereof. Each lateral movement of a ply being produced with respect to the assembly plane is carried out by the synchronized movement of a table with which the lower face of the ply is in contact and a driver with which the upper face of the ply is in contact. There is an installation for implementing the method according to the invention.