HISTORIC SCOTLAND TAN 15 EXTE~YAL LIAIBCOATINGS ON TRADITIONAL BUILDINGS
Smooth rendel; sometimes krlown as stucco, is less common in vernacular building. It sometimes had 'lining-out' drawn o~ltothe surface in imitation of ashlar blocks. As flat finishes (or 'renders') became more common on many town buildings and couiltry houses throughout Britain during the eighteenth and nineteenth centuries new materials were being developed, including hydraulic lime mortars, Roman cements, other patented cements such as Keene's cement, and mastic stuccoes. The extent to which such materials were used, and the frequency of occuisence of smoother finishes in Scotland is not well understood at present.
1.3.3 Modelled arzd decorative srirfaces. External coatings in Scotland are generally found to be quite plain, with little evidence of applied decoration when compared with finishes such as plaster pargetting in England and decorative renaissance plaster relief work found in parts of Europe. This is not to say, however, that more elaborate external finishes never existed, and any evidence which might be found for more decorative finishes should be carefully protected and recorded.
Fig. 7 Herklei-11,ickHouse. 'Tirize ' A sigiz$cuizt esanzple of e.rteriza1 rlecorntii~eplnsfei71,ol-kis recorded in photoglz~phsof tlze Olcl Ho~lseof Hedclei~~ick, izeni-Moiitlase (held iiz tlze Nr~tionalMorz~l17zeizt.s Records irz EdiilD~~rgh). NOIVdeiizoli~I~eCI, this h o u ~ eof c. 1700 lznd n lined-ant siiiootl~li171erenrlei; 17~ii~zicking$ize a.shla7; ,t,if/z plaster egg-and-clart ii~o~~lrlerl ltiirzdoir, 01-chitm~ses, nrid n high relief .fplnster sc~iI~)tz~i.e.
Locally distinctive characteristics in surface finishes can derive from variations in the underlying construction, variations in methods of applicatio~land finishing, and from variations in the constituents of the mortar inixes used for surfacc coating. A common surface finish in the north east of Scotland is sneck harling, which appears as a partial harling to the walls, with the faces of larger stones remaining uncovered. This type of finish may originally have been caisied out by casting a coarse lime mortar into the hollows between rounded field boulders (which were used in construction dui-ing first stage agricultural improvements of the second half of the eighteenth century) or it might result from the partial weathering away of a fill1 harl coating. The resultant appearance may thus be a function of the technology rather than a conscioi~sdesign decision, although later examples of sneck harling may be a deliberate technique derived earlier traditions.
Fzg. S Siieck harlzrzg, Barzffshire.