Brick garden walls were sometimes built with a cavity in them to allow warm air move through, to encourage fruit growth. Came across one of these walls in Kildare recently. 

With large estates the guarantee of a food source was high on the agenda. This led to great innovation in gardening and food production. Brick faced walls rose in popularity because they absorbed the heat of the sun and provided a warm wall. This encouraged growth of fruit etc.  

The absence of a warm sun and the risk of frost meant that alternative solutions had to be considered. Heat sources such as a furnace with flues built into or adjacent to the walls directed heat/exhaust into the wall cavity through tunnels or pipes.

Evidence suggests that someone wanted to take advantage of this cavity more recently to run new services through them.    

#conservation #heritage #orchards #gardenwalls #brickgardenwalls #scsi #construction #gardening #innovation #growth #food