BS 8103-1:2011

This standard BS 8103-1:2011 Structural design of low-rise buildings is classified in these ICS categories:

• 93.020 Earthworks. Excavations. Foundation construction. Underground works
• 91.040.30 Residential buildings

This part of BS 8103 gives recommendations for the structural design of low-rise housing and covers the stability of the structure, site investigation and foundations and ground floor slabs used in the construction. Foundations comprising strip footings or trench fill founded in normal ground are the only type described.

Low-rise housing comprises detached, semi-detached and terraced houses and flats (with not more than four self-contained dwelling units per floor accessible from one staircase), of not more than three storeys above ground intended for domestic occupation and of traditional masonry construction with timber roofs and floors of timber or concrete. For the purposes of this standard, additional habitable accommodation in the roof space constitutes a storey of the house. The recommendations also apply to certain single storey, non-residential buildings, e.g. domestic garages and annexes to residential buildings with a floor area not exceeding 36 m². This standard does not include the design of basements but, providing the basement is of one level only and is designed to provide a firm platform at ground level, the provisions of this standard may apply to the superstructure.

Proprietary housing systems and houses of timber, steel or concrete framed construction are not covered by this standard.

The structural design recommendations described in this standard are not specifically intended to cover other considerations such as fire resistance, thermal and sound insulation, resistance to damp penetration and durability.

For the purposes of this part of BS 8103, the following limitations apply:

1. roof: maximum clear span 12.0 m;

2. floor: maximum clear span 6.0 m;

3. a dynamic wind pressure not exceeding a value of 1.2 kN/m² (see 4.3);

4. no part of wall or roof higher than 15 m above lowest adjacent ground level;

5. storey height: maximum 2.7 m;

6. maximum clear length of a loadbearing wall between vertical lateral supports of 9.0 m;

7. maximum length of any opening in loadbearing walls: 3.0 m;

8. only strip footings or trench fill foundations in normal ground conditions (see 6.1).

NOTE Where foundations other than those given in item h) have been designed by suitably qualified persons, the remainder of the building may be constructed in accordance with the relevant clauses of this standard.