Boveda ceiling crumbling

[CHILLIN]

I know you probably have no intentions to become a mason. Good bricks, and good terracotta, give a strong, musical "tink' sound if you tap them with a piece of metal, bad bricks give a sort of "thud" sound. It will be the same when your mason checks out the boveda, tapping around. Wet, rotting areas will give off a "thud" sound. The worst sound you want to hear is a hollow "thoc" sound, which means the salitre has washed away all the cement holding your wall surface in place. While there are some complicated backfill solutions used in Europe, here it is cheaper and faster to just repair the same way they have always been doing it.