Building (Amendment) Regulations (Northern Ireland) 1998

Regulation 6

SCHEDULE 2 Part to be substituted for Part D (Structure) of the principal Regulations.

Part D Structure

D1 Stability

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.

D2 Deemed-to-satisfy provisions for stability

The requirements of regulation D1 shall be deemed to be satisfied if—

(a) the loads to which a building will be subjected are calculated in accordance with, in the case of—

(i) dead and imposed loads (excluding imposed roof loads) – BS 6399: Part 1: 1996;

(ii) imposed roof loads – BS 6399: Part 3: 1988; and

(iii) wind loads—

(A) BS 6399: Part 2: 1997; or

(B) CP 3: Chapter V: Part 2: 1972 (in no case shall S3 be taken as less than 1):

Provided that—

(A) the actual loads are used, where the actual loads to which a building is to be subjected is likely to exceed the loads so calculated; and

(B) loads used allow for possible dynamic, concentrated and peak load effects which may occur; and

(b) the design and construction of the work is carried out in accordance with the relevant recommendations of the following documents, that is to say, in the case of—

(i) foundations—

(A) BS 8004: 1986; or

(B) DOE(NI) Technical Booklet D: 1994: Sections 1 and 5 (for houses and small buildings);

(ii) structural work of reinforced, prestressed or plain concrete—

(A) BS 8110: Part 1: 1997, BS 8110: Part 2: 1985 and

(B) BS 8110: Part 3: 1985;

(iii) structural work of steel—

(A) BS 449: Part 2: 1969; or

(B) BS 5950: Part 1: 1990, BS 5950: Part 2: 1992 and BS 5950: Part 5: 1987;

(iv) structural work of composite steel and concrete construction—

• BS 5950: Part 3: Section 3.1: 1990 and BS 5950: Part 4: 1994;

(v) structural work of aluminium—

(A) CP 118: 1969 using one of the principal or supplementary aluminium alloys designated in Section 1.1 of that Code, and for the purpose of Section 5.3 of that Code, the structure shall be classified as a safe-life structure; or

(B) BS 8118: Part 1: 1991 and BS 8118: Part 2: 1991;

(vi) structural work of masonry—

(A) BS 5628: Part 1: 1992, BS 5628: Part 2: 1995 and BS 5628: Part 3: 1985; or

(B) DOE (NI) Technical Booklet D: 1994: Sections 1, 3 and 4 (for residential buildings of not more than 3 storeys, small single storey non-residential buildings and small buildings forming annexes to residential buildings (including garages and outbuildings)); and

(vii) structural work of timber—

(A) BS 5268: Part 2: 1996 and BS 5268: Part 3: 1998; or

(B) DOE (NI) Technical Booklet D: 1994: Sections 1 and 2 (for single family houses of not more than 3 storeys).

D3 Disproportionate collapse

(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.

D4 Deemed-to-satisfy provisions for disproportionate collapse

The requirements of regulation D3 shall be deemed to be satisfied in relation to a building if the design and construction of the work on that building is in accordance with—

(a) the relevant recommendations of the following documents (taking account of the recommendations on ties and on the effect of misuse or accident), that is to say, in the case of—

(i) structural work of reinforced, prestressed or plain concrete—

• BS 8110: Part 1: 1997 and BS 8110: Part 2: 1985;

(ii) structural work of steel—

• BS 5950: Part 1: 1990 (the accidental loading referred to in clause 2.4.5.5 shall be chosen having particular regard to the importance of the key elements and the consequences of failure, and the key element shall always be capable of withstanding a load of at least 34 kN/m² applied from any direction); and

(iii) structural work of masonry—

• BS 5628: Part 1: 1992; and

(b) the procedures contained in DOE (NI) Technical Booklet D: 1994: Section 6.