IRONWORK REPAIRS IN TIMBER-FRAMED BUILDINGS.
It has been seen from
the gathering of samples during fieldwork that there is a very definite assemblage
of types of iron-work repairs that can be identified. Above all there are
a number of fixed forms which have passed down the centuries with the most
prevalent being the L-ties.
The age of these components
can be estimated by their typological features: how they are made and of what
material. There are some very definite historical cut-off points. Charcoal
iron precedes coak produced iron which was available only from the 18th century.
Puddled milled iron became available after 1784.
such as Neve in 1726 indicate that only English and German iron was used for
the base work such as the making of firebars and undoubtedly wrought-iron
ties, then commonly known as dogs. Quality and large work may have been made
of Spanish iron.
of the properties of wrought iron was achieved by experimentation in the mid
19th century and led to the reduction of material cross-sections. This coupled
with the availability of mass-produced components meant a Victorian uniformity
was achieved in iron-work repairs.
Availability of wrought
iron peaked in the mid 1800's until in 1856 mild steel was discovered and
quickly superseded wrought iron for most uses. The simple iron tie most certainly
would have been made of mild steel within only a few decades of its discovery.
Fixtures such as nails
and screws have a closely recorded typological sequence and could be invaluable
for dating repairs. Other fixtures such as staples may prove to be of no use
in trying to establish a dating sequence as their form is virtually unchanged
until the 20th century.
By developing an appreciation
of the engineering principles of the wrought-iron tie, components that are
both ductile, strong and resistant to repetitive stress failure we may draw
on historic precednts to designs today's repair solutions.
8.3 Future Directions
It has been the aim of
this work to promote a general awareness of the chronologies and typologies
of historic ironwork repairs and their fixings and thus encourage effective
recording of ironwork repairs to timber-framed buildings. These records could
be descriptive photographic, drawn or even physical archives of removed fixings.
It is hoped that by doing
so there will be a development of general and regional typologies that may
be used in the accurate dating of building repairs and also to promote further
research into the historic and technological value of ironwork repairs.
It may be possible to
expand our knowledge as to why timber-frames fail and how ironwork repairs
can indicate these failures. This knowledge would be invaluable when condition
surveys are required or repair strategies formulated.
Repair strategies based
on historical repairs contemporary with the timber-frame and its existing
ironwork repairs can then be employed in preference to modern, intrusive repairs
where cost is artificially given priority over form and function.
The use of real wrought
iron must be considered as the preferred metal for historic ironwork repairs
and this demands an awareness of the availability of wrought iron and compatible
There is a genuine need
for archaeologists and architects alike to recognise that historic repairs
are of great interest, both as an intrinsic part of the history of the buildings
but also as steer for modern repair strategies.