Existing foundation on left, addition to be on right. Existing not down to frost line, addition will be down to frost line. Not built yet. Soil is decomposed granite, rocky, drains well. Addition is single story, as is existing cabin. Gable wall to gable wall. Best way to tie these together, or isolate the two? Thanks in advance.
A properly installed 4-in. corrugated drainage pipe running under a driveway can withstand the pressure of a 40,000-lb. truck.
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Replies
You have to decide whether you want to tie them together or isolate them. If the soil were clay or loam then a frozen foundation would produce significant heave, and if the foundations were tied together there would be serious damage. Hard to say in your specific conditions.
You probably need to tie them together to stop the addition from pulling away from the older part. Rebar in drilled holes and epoxied in place is the standard technique. Your mason can tell you more.
Yes, DanH is right.