There is a surprisingly wide choice of materials with which to construct shelving units.

Moulded plastic shelf racks are easy and quick to assemble as well as being unaffected by the damp. Since there are various designs it is recommended that you check the shelf unit, after you have assembled it, for stability. If it is not totally stable then you need to secure it to a wall. One of the limitations of shelving units constructed from plastic is that it is difficult to modify them in order to make larger systems or customised assemblies.

Bamboo and willow can make unusual and rather attractive shelving units. However they are only really useful for very light usage. They are excellent as display units for example, or as shelf storage space for bed linen, towels or clothes.

Now and again, it is possible to stack breeze blocks as support for wooden shelves. If the unit is well designed and well built it will make for a strong unit. However, if there are not sufficient means to withstand sideways forces, these units can become unstable without warning and therefore unsafe.

Chipboard is okay for quite a few uses around the house, but does tend to sag after a while and has very little water resistance. When used in shelves, it is recommended that it rests on supporting rails on all four sides.

Plywood is a lot tougher than chipboard and WBP plywood is water resistant. OSB is a cheap alternative to plywood.