I have worked on Poplar log homes in the past and they do well if they are kept absolutely dry. Large overhangs are a must – 4′. They must be dry when used and a good borate like Shell Guard a must also. Mortar would be the cheapest, but it will allow leaking which can lead to rot. Do it right the first time and use Grip Strip backer and Perma Chink chinking. Cal Dave at 800-564-2987 for the materials you will need or go to www.timelesswoodcare.com
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