any ex-mason's out there?

Originally Posted By: jnosworthy
This post was automatically imported from our archived forum.

What would you think if: the house is two years old, level lot, fair drainage, sandy soil, dry crawl space, no current signs of moisture infiltation. We have about 2 1/2 courses of cinder block foundation showing. the face of which is parged. 13 out of 15 standard metal foundation vents show a single vertical hairline crack in the block course immediately below the vent, at the vertical mortar joint joining the two blocks below. These same cinder blocks do show a crack on the inside face of the same block. Only one other foundation block crack is apparent, and that is located at a corner. Got any ideas as to what may have helped allow this to happen ?? Thanks, John

Originally Posted By: mcyr
This post was automatically imported from our archived forum.


Hi John;

Not knowing the exacts, I would have to assume that the hairline cracks are similar to concrete. The parging on the blocks will not be as conducive to movement as exposed block. The mortar joints and the block will move without to much noticeable hairline cracks. Since the blockwork was parged, the thin coating is not as elastic as the bare block and joint. Therefore, cracking of this skin coat will be more prominent.

Hope this helps.