To the many visitors to this area no doubt the drystone field walls and the apparently similar house walls all look much the same.

In fact even when built there were already differences in construction between a field wall and a house or outbuilding wall.

The general construction of an outer layer, an inner layer and 'through' stones to bind the two layers together seems to have emerged in the 17th C. The great building boom seems to have started in 1661, given the number of date stones I've seen from around this time in Grasmere. There are one or two buildings in the area which date from 1570s but have later additions disguising them. These earlier buildings tend to have thicker walls than the 17th C building walls. Barns are built with ventilation in mind but houses much less so, other than for smoke-hoods which sat on the last ceiling beam before the fire and connected to a stone chimney.

From observation a general standard seems to have emerged during the 17th C of having house and barn walls approximately 2 feet (603 mm) thick overall plus plaster internally on house walls with small outbuildings and internal walls at 1 foot (304 mm) or 1 foot 6 inch (450 mm).

It is thought that clay was sometimes used in building walls to bed the inner stone walls but set well back from the external face to avoid being washed out by rain. Clay was eventually replaced with lime mortar during the 18th C but the practice of keeping it well back from the external face persisted.

Generally the older the building the bigger the stones at the base of walls it seems (or sometimes the builders set off from a large cobble (boulder) in a field or a shelf of rock (leading to problems if you decided to lower the floor of the building).

Despite the massive waste heaps from past mining and quarrying of slate obtaining building and roofing slate has become very tricky. Honister mine, beyond the end of Borrowdale still produces a high quality green slate but it is expensive. 2nd hand Westmorland Green is often hard to find nowadays in any quantity. 'Diminished courses' - where rows of slates become shorter towards the apex of the roof - is a local feature of slate roofs and often quoted in Conditions on planning approvals. Lack of suitable slate leads some roofers to skimp on the number of courses diminishing or avoid the detail altogether, risking an argument with knowledgeable locals and the LDNPA enforcement team.

Walling stone tends to come from leased areas of old workings and spoil heaps such as at Hodge Close, off the road to Coniston from Ambleside. We are fortunate to still have skilled wallers working locally.

Burlington Slate own or control most of the slate quarries in the area apart from Honister. They offer a range of stone colours and finishes but probably best to talk to them about availability if you need a particular stone or slate well in advance of building work.