Unexplained sudden mortar deterioration
A family member sent me these pictures from the exterior of his house in Ohio. The house is a little over 100 years old. You can see the mortar is seriously deteriorating. A ton of powder is at the base of the brick. It is near a downspout but covered by the roof overhang. I told him it needed to be repointed but he insists the mortar was fine last month. He walks by the area regularly. It appeared out of nowhere. He said nobody has been to work on the house, no seismic activity, etc. Normal freeze thaw cycle can do this but I’d expect it to happen more gradually.
Could any critter be responsible for this? Any ideas what the root cause is? I said type N mortar is probably best but I’m not 100% sure.
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