(1) For the purposes of this section –

“structural damage” shall mean a cracking, spalling or crumbling of the surface of the wall which is readily visible to the naked eye. The fracture of glass in adjacent windows or damage to applied finished shall not be deemed to be structural damage to the wall;

“structural failure” shall mean collapse of the wall or a portion of the wall, or holding of the wall;

“load factor” shall mean the quotient found when that load which causes the first signs of structural damage or structural failure, as the case may be , is divided by the maximum load which the walls are designed to support.

(2) If the walls of a building are to be constructed of materials or building-units not specified in this Chapter, the local authority may call for tests to be conducted, or a report submitted, according to the provisions of Chapter 2, and shall prohibit the use of such materials or units unless the results of the tests demonstrate or the report shows, that such walls comply with such of the following requirements as are, in the opinion of the local authority, applicable to them-

a) when loaded with static loads, the walls shall provide load factors for structural damage and for structural failure not less than those considered satisfactory by the local authority for the material and method of construction concerned;

b) the walls shall withstand the impact test set out in the First Schedule;

c) the deflection, under design load, at the center of walls which are to be plastered shall not exceed 1/360 of the distance between lateral supports, and that of walls which are not to be plastered shall not exceed 1/240 of such distances;

d) when testes for moisture penetration as described in the Second Schedule, walls shall not show visible dampness on the inside surface to the extent specified within a lesser period than set out in the Table in that Schedule for the appropriate conditions;

e) the construction shall be shown to be, or be assessed as being

i) durable; and

ii) stable under variations in load, and under variations in temperature and moisture content which are due to climatic conditions.