I have a front garden wall approx 50cm high x 5 meters. It is straight and level but the bricks are well weathered. I am to take this down and replace it with a wall constructed of a brick pillar at each end and single skin breeze block connecting the pillars (which will be rendered and painted) approx 1200mm in height. Therefore this is a lightweight construction? I would like to use the existing foundation due to costs mainly. Is there any way of checking how good the foundation is? Does this sound feasible? Advice welcome please.