Basement Waterproofing a Basement that has Structural Clay Walls Using Weep Holes

That's structural terra cotta. historicbldgs.com/terra_cotta.html If it is vitrified (and not just shiny from being wet) and the long edges are rounded, it could be telephone tile. historicbldgs.com/telephone_tile.html If it's not vitrified, then the shell is quite brittle. Ask your contractor to show you how well he drills the sides of flower pots. I've seen plenty of attempts at drilling - for termite treatments and installing anchors - that have blown out very large sections. I don't much care for adding interior drain systems. I never thought letting even more water into a basement and constantly pumping it back out is a good idea. At best, it's the absolute last resort after exhausting every other possible solution. The system, and even the installation, has caused serious problems in some buildings. I've had plenty of expert witness jobs that are from waterproofing contractors irreversibly damaging old building foundations, including catastrophic failures. These systems are intended for modern foundations with pretty standard footings.

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