We often see mortar chinking in older log homes. It was mainly used from the 1950’s through the 1980’s. The problem with this type of chinking is twofold:1. It doesn’t make a proper seal between the logs.2. It tends to hold moisture up against the logs, possibly adding to the potential for rot.Today, synthetic chinking such as the Perma-Chink  brand is routinely used instead of mortar. This “modern” chinking has much the same appearance as the old mortar but, unlike mortar, it will seal completely and not soak up moisture, which will help to prevent rot.Many times, new chink can be applied over existing mortar chinking but in other situations, the mortar chink needs to be removed before the synthetic chink can be installed. It’s good to get a professional opinion to decide which is the right fix. Call 715-373-5744 to get your questions answered.