French term (edited): alv�olaire

Note: the 'lames' are probably extruded PVC, of cellular construction in the longitudinal sense.

On the other hand, the door could be a standard honeycomb construction type of panel door, as is common these days (plywood faces with cardboard interior!) --- you need to know whether it too is PVC or not... Or even the type with a cellular foam core (but both of these are more common for interior doors than exterior ones)