https://loghomejourney.wordpress.com...chinking-post/ I used the calculator at the permachink website - my average gap is about 4", and about 2" deep x 40 foot long walls x 20 feet tall (15 lines of chink x 2 (inside / outside)) x 4 walls is how they figured it = $14,000 for their stuff. Traditional mortar chink = 1 wall takes about a bag of portland cement ($18), 4 bags of lime ($4 each), and probably 1/2 ton of sand ($23). So 1 wall, outside only: 18 + 16 + ...