KVPT’s Patan Darbar Earthquake Response Campaign - Work to Date - September 2016

Manimandapa south
The rotten base beam for the pillars
and timber pillars in storage.
Photographs by Rohit Ranjitkar, July and
August, 2015.
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our priority is to return to the original materials and
configuration of the historic structure, and provide improved
performance as needed (where historic materials
are not sufficient) through concealed, or unobtrusive,
modern interventions.
In roofing assemblies, this translates to achieving improved
waterproofing and seismic bracing via the addition,
concealed above the planking on the rafters, of
marine grade plywood and a waterproofing membrane
under the traditional mud setting bed and jhinghati roof
tiles. The Mul Cok and Sundari Cok projects in Patan
Palace are recent examples of this approach to roof assembly.
The word “traditional” today is a confused term which
is often unwittingly used in a way that conflates original
and later materials. For example, in addition to the
larger tiles and bricks mentioned above, later materials
include wood planking over rafters. Most people in Nepal
today consider this a traditional material and would
be surprised to learn that the use of planking in this way
dates back only to the Hanuman Dhoka and Bhaktapur
Development Projects (1970’s-80’s). Where roofing
materials of 85 years or more survive, one probably
finds a mixture of reeds and lathe used to cover the rafters
under the mud bed; and while this may have been
conventional practice for centuries, there have also been
found early surviving fragments of specialty tiles used to
span the rafters, - possibly the earliest building practice,
according to Gutschow.
Certain clearly modern materials are such common and
obvious improvements to the performance of traditional
buildings that they have become de facto strategy for historic
buildings. One of the most common examples is
the waterproofing membrane under the mud bed of the
roof. This ahistorical material is generally accepted as
a modern intervention which the old buildings require
to survive the monsoon cycle. There is no controversy
over whether this modern innovation is the best way
to waterproof roofs. One could consider that any such
modification shifts the balance, subtly or less so, of historical
and traditional assemblies, and with it, some not
fully determinate factors in the structures’ durability and
earthquake resistance - for better or for worse. But this
membrane is concealed, it works, and it is rarely discussed.
This is also important because of the existence of a vocal
faction which argues today against the use of modern
materials. Like everyone else, this group accepts such
modern materials as the waterproof membrane, and it
has even proposed the use of laminated timber - (wood,
yes, but a very industrial, ahistorical material-arguably
more modern than concrete). The ideology here of rejecting
modern materials is restricted to concrete, as discussed
elsewhere in this chapter. There has been some
discussion about the use of timbers in ahistorical configurations
- even a proposal for a timber ring beam in
a foundation. Mention has even been made of substituting
an enormous monolithic stone for our proposed
concealed foundation slab on a project in order to avoid
any use of concrete.
It is our conclusion that these ideas are not practical in
terms of implementation and durability, and they do not
withstand scientific scrutiny or conform to international
norms of preservation. It is worth reemphasizing that -
with the rare exception of an historical change that was
of a high quality of design and material, rather than a
downgrading of materials - our priority is rather a return
to the original historic configuration (form and dimensions)
and materials wherever possible, with a carefully
considered intervention using concealed or unobtrusive
modern materials only when traditional materials
cannot meet the need. This is Article 10 of the Venice
Charter, painstakingly applied.