u/Illustrious_Owl1197

Working on a SFH addition project. Existing is rubble foundation (very good condition).

Wondering how others handle the transition between existing and new foundation walls/footings.

Curious what the typical approach is in your practice..

Are you doweling/pinning the new footing/wall into the existing?Or keeping them independent with a joint?

Doweling/pinning the old and new foundation together feels right from a continuity standpoint, but seems weird doing it to a rubble foundation. Also doweling/pinning foundations always made me think about the possibilties of differential settlement

And no ... there is no geotech report (which honestly seems to be the norm for these smaller residential additions) but almost certain this isnt clay