Broad regional and local patterning of the house and settlement record has been clear for decades, and underpinned Piggott's ( 1966) justification of the delineation of his provinces and regions (see theme 3.3). There is a broad distinction between the stone roundhouse forms of north and west Scotland and the timber houses of south and east Scotland, where the greater diversity of building structural form may imply the existence of a more complex or more varied society (Armit 2002; Henderson 2007a, 126-7). However, there were timber roundhouses in the former area, and stone ones in the latter. Distinct regional identities probably exist, but there are few well defined boundaries to distributions, and much transgression (Haselgrove et al. 2001, 23). Cunliffe ( 2005, 73-5) makes a broad distinction between Atlantic and western Scotland as dominated by strongly-defended homesteads of single family units, and southern and eastern Scotland as a hillfort-dominated zone interpreted as reflecting communal activity of large groups of people based in a range of other subsidiary settlements. This is an acknowledged over-simplification, masking intra-regional and local diversity (see also Harding 2006 ).
Different levels of archaeological survival are, broadly speaking, the product of an east versus west, lowland versus highland, timber versus stone divide. Better preservation of stone architecture in the west allows us to understand the characteristics of buildings, sequences and change over time better than the often plough-truncated remains of timber roundhouses in the eastern lowlands. In the south-east the unique preservation of timber structural traces in the resilient turf of the Cheviot Hills has, to some extent, counter-balanced this tendency and excavations at Kintore (Cook & Dunbar 2008) have shown that when examined intensively on a large enough scale developments over time in roundhouse form can be traced. Burnt-down houses present a particularly valuable resource, as Barber's (1997) analysis of the Bronze Age example from Tormore (Arran), Hodgson's (2001) work on the later Iron Age one from South Shields (Tyne & Wear), or Sharples' (1998) analysis of the burnt layers at Scalloway, amply illustrate. This requires considerable investment in careful excavation and analysis.
- Issues concerning raw materials and resource availability (particularly timber and stone) require further exploration, in both chronological and cultural terms, including comparisons between Atlantic and non-Atlantic traditions, but also more nuanced comparisons, including topics such as the South-east vs. South-west chronological distinction in timber usage for buildings (RCAHMS 1997).
- Burnt-down houses represent a particularly valuable resource which needs to be seized with careful work in the field and in the lab.