Pin small concrete porch to ICF Basement Wall?
tbanwart
| Posted in General Questions on
I am building a small 8×6 front porch in front of our ICF home. We have a peel n’ stick membrane / dimple board and clean gravel against basement ICF wall and want to pour a monolithic footer / short 20″ tall wall / slab in single pour. My question is if we should drill in & rebar tie the slab / footing of the porch into the ICF wall. It could help with any movement, but also heard some advise against connecting the porch to the wall this way. It would thermally bridge porch slab to ICF wall, but may not be a huge penalty. What is everyone’s thoughts? Pin or not pin. See picture (still have more rebar to add)
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Replies
Pins will have a very small impact on thermal performance and will help with differential settling. If the ground is properly prepared, the porch shouldn't settle so the pins should not be necessary, but they are easy insurance in case there is settling.
ss dowels or epoxy-coated rebar is good. Extend the WP membrane out onto the dowel in accordance with the peel-and-stick membrane manufacturer's requirements for penetrations. typically that's 4"-6" onto the rebar which puts it into the new slab/footer.