By 1113 AD the Cistercian order had ruled that any new monastery must have an oratory, a porter’s cell, a dormitory, a refectory and a guest-house before it could be occupied. This would immediately allow the new community to serve God and live in religious discipline. In general, monks were expected to remain cloistered within their monastery and perform liturgy on behalf of all Christians. Consequently, they were viewed by the general populace as being closer to God and more likely to secure divine intercession on behalf of mankind. If monks were to remain cloistered they needed land or estates, worked by lay-brothers, which would produce income to pay for clothing, buildings, vestments and books.
A monastery was sustained by revenues and produce from lands granted to the house by the founder and subsequent secular patrons. Often, these lands formed a discrete block of territory and surplus cash revenue belonging to the monastery could be used to make further investments in land and property. Monasteries probably specialised in particular economic fields: Melrose , for example, found a ready market for wool in Berwick and quickly concentrated on sheep farming. Initially, it is clear that the Cistercian order developed a simple framework for their ideal of monastic life. The first Cistercian buildings in France were wooden structures, built to an exact plan, and roofed with thatch. Archaeologists have also found traces of such buildings in some of the early Cistercian establishments in England . However, as soon as a new establishment acquired sufficient lands, monks and lay-brothers to ensure that the foundation would succeed, new buildings were built in stone. As with the original wooden structures, the Cistercians built in stone to an exact plan and, on occasion, communities were ordered to demolish buildings that did not conform to the Cistercian norm.
It would appear that from c.1150 AD the Cistercians built two different types of monasteries in Britain. Larger establishments, like Rievaulx and Melrose , housed communities of more than one hundred monks, and smaller communities might consist of around fifty monks. Judging by the architecture, Deer abbey would have been one of these smaller communities. In a monastery the lay-brothers occupied the west range of buildings: archaeological evidence from Rievaulx and Melrose shows that the west range could be two stories high but that internal walling kept the lay-brothers quite separate from the cloister and contact with the monks. It is likely that the nave of the church would also have been divided into two discrete areas by a screen: one area for lay-brothers and one for monks. Contact with lay-brothers would have diverted the monks from their allotted tasks.
However, unlike the twelfth-century Cistercian foundations in Scotland, such as Melrose, Kinloss, Dundrennan and Newbattle, the thirteenth-century foundations – Balmerino, Deer and Sweetheart – do not seem to have built extensive, or any, West ranges to accommodate lay-brothers. There is some evidence to suggest that by the late twelfth century lay-brothers had begun to resent the harsh working and living conditions imposed on them by the Cistercian order. From c.1208 AD, Cistercian monasteries began to lease out some of their lands rather than rely on lay-brothers to work them. Another factor in the decline in recruitment of lay-brothers may have been the formation (around 1200 AD) of orders of Friars, particularly Franciscans and Dominicans. Initially, these new orders did not need endowments of lands and Friars were not cloistered. They could move freely throughout Christendom to wherever they would do most good. Consequently, the monastic orders began to decline in popularity and the orders of Friars largely took over the job of advancing the frontiers of Latin Christendom.