a. It should be durable against the adverse effects of various agencies such as wind, rain, sun etc.\

b. It should grant the desirable insulation against heat.

c. It should be structurally stable and sound, it should be capable of taking the loads likely to come over it.

d. It should be well-drained

e. It should have efficient water-proofing arrangement.

f. It should provide adequate thermal insulation.

g. It should have adequate insulation against sound. In short, it must be sound proof from external agencies.