Under our concrete entrance staircase, there is a space intended as a food//potato cellar.
When I was sanding off old paint and deposits today, I noticed that the plaster was loose in one corner and came off very easily. Behind the plaster, there are lightweight concrete blocks, and there was about 5 mm of air between the blocks and the plaster. Some of the lightweight concrete blocks are completely loose and could probably be manipulated off entirely, others have completely cracked. The mortar between the blocks has entirely turned to sand. See pictures below
As usual, water is the culprit, and it's probably due to the slightly skimpy entrance roof and its deficient drainage (runoff occurs via the small pin to the left in the picture, and when it rains, water often pools on top of the stairs) see exterior image:
I guess the first step is to remove the water. A proper gutter and downpipe to lead the water away would probably offer a clear improvement, but is there a simple way to address the roof size? The current construction is a (quite shabby) metal roof on a concrete slab. Can a larger roof be added without having to extend the concrete slab?
Once the moisture situation is improved, what's the best way to fix the food cellar? Should the loose and damaged lightweight concrete blocks be replaced and newly mortared in with fresh mortar, or is it better to just spread on some house fix or similar and secure them where they are?
