Big gaps happen!!! and when you don't have a stone stretcher YOU CAULK IT!!! But what is the best way?
Instagram @vancouver_carpenter
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Here is the backer rod:
1/4" https://amzn.to/3d128BE
3/8" https://amzn.to/2VR1kto
1/2" https://amzn.to/2yTdGIf
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