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4
Single-Storey Frames, Shells and
Lightweight Coverings
This chapter describes the construction of single-storey buildings such as sheds, warehouses,
factories, lightweight mast and fabric structures, and other buildings, generally built
on one floor and constructed with a structural frame of steel or reinforced concrete supporting
lightweight roof and wall coverings (see also Chapters 5–7). A large proportion of
the buildings in this category are constructed to serve a very specific purpose for a relatively
short period of time, after which the market and hence the required performance of the
building will have changed. It is not uncommon for sheds and warehouses to have a specified
design life of between 15 and 30 years. After this time, the building is demolished or
deconstructed and materials recovered, reused and recycled. Alternatively (and less likely)
considerable works of repair and renewal are required to maintain minimum standards
of comfort and appearance. As a consequence, the materials used are selected primarily
for economy of initial cost, tend to have limited durability and are often prone to damage
in use.
In traditional building forms, one material could serve several functional requirements;
e.g. a solid loadbearing brick wall provides strength, stability, exclusion of wind and rain,
resistance to fire, and to a small extent thermal and sound insulation. In contrast the materials
used in the construction of lightweight structures are, in the main, selected to perform
specific functions. For example, steel sheeting is used as a weather envelope and to support
imposed loads, layers of insulation for thermal and sound resistance, thin plastic sheets for
daylight, and a slender frame to support the envelope and imposed loads. The inclusion of
one material for a specific purpose is likely to have a significant impact on the performance
of adjacent materials; thus the designer needs to look at the performance of individual
materials and the performance of the whole assembly.
4.1 Lattice truss, beam, portal frame and flat roof structures
To reduce the volume of roof space that has to be heated and also to reduce the visual
impact of the roof area, it is common practice to construct single-storey buildings with
low-pitch roof frames, either as portal frames or as lattice beam or rafter frames (Figure
4.1). The pitch may be as low as 2.5°. Alternatively flat roof structures may be used.
Barry’s Advanced Construction of Buildings, Third Edition. Stephen Emmitt and Christopher A. Gorse.
© 2014 John Wiley & Sons, Ltd. Published 2014 by John Wiley & Sons, Ltd.
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