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T H E B U I L D I N G C O N S E R VAT I O N D I R E C T O R Y 2 0 1 4
T W E N T Y F I R S T E D I T I O N
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PROFESSIONAL SERVICES
staircases in a building may denote differences
in status between different areas and help
to identify the ways in which a building was
occupied and used. The means by which a
staircase is constructed may also demonstrate
historic methods of joinery and craftsmanship.
The fabric of the staircase not only
provides the tangible evidence upon which an
understanding of it is based but may also yield
further information through more in-depth
investigation. It is sometimes possible to date
a staircase by dendrochronological means but
more frequently the potential to learn more
lies in concealed historic fabric which may be
exposed through repair or alteration work.
Significance might also be derived
through association, for example if the
staircase is known to have been designed by
a particular architect or commissioned by
a well-known person or family. It may also
derive significance by virtue of its belonging to
a particular building.
Where a staircase is not bounded on both
sides by a wall, there is an obvious need to
provide a safety barrier. The incorporation
of a balustrade not only satisfies this basic
function but, frequently being located in the
main entrance or thoroughfare of a building,
also provides the perfect opportunity to use
design to impress. As such, there is often
substantial scope to ascribe significance on
account of a staircase’s aesthetic value.
COMMON DEFECTS, MANAGEMENT
AND MAINTENANCE
Most defects are likely to arise through
general wear and tear, accidental damage,
inadequate control of damp, repeated
exposure to fluctuations in temperature and
relative humidity, or inappropriate repairs.
Many of these risks can be minimised
and their consequences delayed through
appropriate management and maintenance,
which will prolong the structural safety of
a staircase and safeguard sensitive historic
fabric for as long as possible.
A degree of wear and tear is usually
inevitable but the volume of traffic can be
reduced in some buildings, particularly those
with more than one staircase or where there
is the potential to add another one in a less
historically sensitive part of the building. If
traffic cannot be reduced, other protective
measures might prove viable, such as the use
of a carpet to form a protective layer. However,
care must be taken when choosing and
fitting a carpet to avoid causing harm to the
underlying structure. An appropriate cleaning
regime will also serve to prevent the build-up
of harmful agents of decay.
Excessive moisture and poor ventilation
can facilitate fungal decay (wet or dry rot)
or provide ideal conditions for wood-boring
beetles. Particularly susceptible areas include
those where a staircase borders an outer wall
or a void over a cellar. Good general building
maintenance will minimise the risks but some
issues, such as moisture in cellars, remain
notoriously problematic.
Frequent fluctuations in temperature
and relative humidity can exacerbate
problems with damp but also lead to problems
associated with the drying-out of timber,
including loosening of components, splitting
and cracking. This is most likely to be a
problem where a staircase is close to a main
entrance, where the repeated opening and
closing of doors to the exterior, coupled with
modern central heating is likely to cause
frequent fluctuations. The general aim here
is to maintain a temperature and relative
humidity within a more stable range, which
might be achieved by lowering heating
controls, or perhaps employing humidifiers or
dehumidifiers.
Prior to the late 16th century, most
staircases were composed of solid timber
or stone treads. Medieval timber staircases
characteristically had triangular-section
treads but these are now rare and the vast
majority of surviving timber staircases are of
composite form, with treads and risers formed
of individual pieces of timber. These are
generally secured by a series of timber wedges
which serve to tighten up the individual
components. Sometimes these become loose
through general wear and tear, or through
fluctuations in atmospheric conditions.
However, if the underside of the stair is readily
accessible it is relatively easy to tighten-up the
joints by tapping the wedges back into place.
REINFORCEMENT, REPAIR AND RENEWAL
Even with appropriate cleaning and
maintenance, a staircase which is in regular
use will eventually need some strengthening
or repair work. This is particularly important
where the safety of the stair is compromised,
for example where treads or nosings are
unstable or excessively worn, or where
balusters or handrails are damaged.
In accordance with English Heritage
guidance, any repair should involve minimum
intervention. This will ensure maximum
retention of historic fabric but should also
reduce the potential for any conflict with
building regulations, and in the case of listed
buildings may avoid the need to obtain listed
building consent.
In some cases the existing structure can
be reinforced with no loss of historic fabric.
For example, unstable treads can be reinforced
through the addition of secondary support.
Where possible, any reinforcement should
be carried out from the underside of the
stair: this might easily be achieved where the
structure is exposed, for example in an under-
stairs cupboard, or over a cellar access, but in
some cases might require removal of discrete
areas of a historic lath and plaster finish.
In such cases, the area of plaster removed
should be kept to a minimum and should be
reinstated in a like-for-like manner. If the
underside of a stair is intended to be seen, the
sweep of the treads forms an essential element
of its design aesthetic so secondary support to
the underside is unlikely to be appropriate.
Some repairs can be undertaken in situ,
for example the gluing of a split baluster or
damaged nosing, while other repairs might
require the fabrication of new pieces, such as
This simple but elegant late 18th-century balustrade
provides a pleasing visual effect. (All photos:
Archaeology South-East)
A decayed stair tread caused by wood-boring beetle infestation
The secondary supports introduced beneath this existing staircase structure have
not resulted in any loss of historic material.
