Wattle & Daub: Craft, Conservation & Wiltshire Case Study
Contents 2 History
3 Craft
3.3 Panel Types
3.4 Staves
3.6 Daub
3.7 Decoration
4.1 Soils
4.1.1 Constituents
4.1.2 Plasticity
4.1.3 Strength
4.1.4 Field Testing
4.1.5 Selection
4.2 Dung
4.2.2 Lignin
4.2.3 Urine
4.2.4 Microbial Debris
4.2.5 The Role of Dung
4.3 Fibre
5.2.3 Maintenance
5.3 Repair
5.3.1 Partial Renewal
5.4 Replacement
5.4.1 Brick Infill
5.4.2 Renewal
6.3 Fieldwork
6.5 Evaluation
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4.2 DungCow dung was habitually used in daub and so one may suppose
there were particular benefits in its inclusion. Unfortunately, there appears to
be no historic reference as to the properties of dung that encouraged its
specification. Recent publications suggest that dung may improve workability and
durability or may act as an additional binder, but supporting evidence is not
given.[62]
Knowledge has also been lost as to whether fresh, old or
weathered dung was
used.[63]
Since there is no historic reference to the dung being old or weathered, it is
conceivable that this is a recent invention resulting from modern attitudes
toward odour and hygiene. In any case, dried and fresh dung differ mainly in the
water content and so are likely to effect only the amount of water, if any,
added during mixing of the daub.
Additionally, it has recently been proposed that the mucus
in cow dung has two effects on earth used for walling: it reacts with lime to
form a gel, increasing strength prior to carbonation of the lime and it
stabilises
clay.[64]
However, most cobs and daubs do not contain lime and so the formation of a gel
seems unconvincing as to why the dung was added.
This illustrates how the literature is unclear as to the active dung component in daub. Therefore, as an attempt to identify the active constituent(s) of dung, a more thorough review of this topic was undertaken, the results of which are presented below. [62]
Ashurst and Ashurst (1988a), p.117 suggest dung was added to improve workability
and durability. Pearson (1992), p.6, and Holmes and Wingate (1997), p.163, both
suggest dung modifies plasticity, acts as a binder and so improves durability.
Wright (1991), p.98, also offers benefits as being improved strength and
resistance to damp. Minke (2000). pp.44-46 states that manure and urine
improve binding, undigested fibre acts as reinforcement and ammonia compounds
are a disinfectant..
[63]
Ashurst and Ashurst (1988a), p.117 suggest ‘old or weathered dung’
was used, yet fresh dung is stated by Reid (1989) and Forrester (1959), p.37.
Minke (2000), p.45, suggests dung should be left one to four days to ferment but
does not state a historical precendent.
[64]
Ashurst and Ashurst (1988a), p.96.
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