The more absorbent bricks often do better. As the majority of moisture tends to enter through the cross joints, a wall built from a non porous brick sends even more water into the joints. Known as the raincoat/overcoat effect.
Indeed, they are a good sponge buffer, but like lime. It didn’t happen many times, but the serious sideways constant stuff found its way…!
It's easier to build a 9inch wall without flushing the internal joints. The headers are not a problem, it's the wall joints in the stretcher courses which tend to make the wall belly out when filled. Once they have gone out there's no chance of getting them back in. Unfortunately all these voids leave loads of passageways for water.
Yup, and these are early 1700s, or a touch before, locally handmade beauties, so wildly irregular meaning lots of packing/voids between stretchers.
