Mattress with different firmness zones

1. A mattress comprising:

(i) a perimeter rail having a head end, a foot end, and two sides, each having an inner surface; and

(ii) at least two rectilinear sections wherein:

each section is attached at least to the inner surfaces of the head end and the foot end of the perimeter rail;

the sections are aligned substantially parallel to each other in a horizontally adjacent relationship;

the sections and the perimeter rail are attached at respective lower faces to a lower resilient layer and at their upper faces to an upper resilient layer;

each section consisting of single housing within which an array of springs is vertically disposed when in a use position; and

each adjacent pair of sections is urged into a spaced-apart relationship by a spacing means to restrict translation of movement between the adjacent pair of sections without obstructing passage of users across the adjacent pair of sections;

wherein

(a) tension of the array of springs for each section is selected to provide a predetermined firmness for that section; and

(b) each spacing means comprises a flexible spacer which is retained along its length between the upper and lower resilient layers and is fixedly attached at its ends to the perimeter rail, and wherein each spacing means extends substantially from the head end to the foot end, wherein the flexible spacer is attached along its length to the coil springs adjacent thereto.