PART DStructure
Stability
D1 A building shall be designed and constructed so that the combined dead, imposed and wind loads are sustained and transmitted to the ground, taking into account the nature of the ground—
(a)safely; and
(b)without impairing the safety of any part of another building.
Disproportionate collapse
D2—(1) A building to which this paragraph applies shall be designed and constructed so that in the event of damage occurring to any part of the building, the extent of any resulting collapse will not be disproportionate to the cause of the damage.
(2) Paragraph (1) applies to a building having 5 or more storeys, counting each basement level as one storey but discounting a storey within a roof space where the slope of the roof does not exceed 70° to the horizontal.
Deemed-to-satisfy provisions for regulations D1 and D2
D3—(1) The requirements of regulation D1 shall be deemed to be satisfied—
(a)if any loadings to which the building will be subjected, specified in column (2) of the Table in Schedule 4, are calculated in accordance with the relevant provisions of the publications specified opposite there to in column (3), as amended by the publications specified opposite thereto in column (4):
Provided that—
(i)the actual loads are used, where the actual loads to which the building is to be subjected are likely to exceed the loads so calculated; and
(ii)loads used allow for possible dynamic, concentrated and peak load effects which may occur; and
(b)in the case of any structural work specified in column (2) of Table D opposite the reference to that regulation, if the structural work is designed and constructed in accordance with the relevant provisions of the publications specified opposite thereto in column (3), as amended by the publications specified opposite thereto in column (4).
(2) The requirements of regulation D2 shall be deemed to be satisfied, in the case of any structural work specified in column (2) of Table D opposite the reference to that regulation, if the structural work is designed and constructed in accordance with the relevant provisions of the publications specified opposite thereto in column (3), as amended by the publications specified opposite thereto in column (4).