As mountain log homes settle and expand through extreme seasonal humidity and freezing winter temperatures, traditional mortar chinking cracks and pulls loose from logs. Failed chinking allows cold drafts, driving rain, and insects to penetrate deep inside exterior walls. We install high-performance elastomeric synthetic chinking and log caulking from Perma-Chink and Sashco that moves dynamically with timber joints to seal out moisture and stop energy loss.
Modern synthetic chinking compounds like Perma-Chink and Sashco Log Jam stretch up to 250 percent of their original joint width without tearing or losing adhesion. The textured finish mimics traditional sandy masonry mortar while providing an impervious barrier against mountain rain and freezing drafts.
Applying sealant directly over wood backing causes three-point adhesion failure when logs shrink. We insert closed-cell polyethylene foam backer rods and bond-breaker tape into log channels, ensuring the sealant adheres strictly to the top and bottom logs while flexing freely in the center.
Natural drying creates lengthwise splits called checks in logs. When checks face upward, rainwater collects inside, accelerating interior rot. We clean out check cavities, insert miniature foam backer rods, and inject color-matched elastic caulking to shed water harmlessly down log faces.
Significant air leakage occurs where round logs meet flat window and door trim. We seal all timber-to-frame interfaces, corner saddle notches, and gable transitions with elastic log caulking, eliminating mountain air infiltration and dramatically lowering winter heating costs.
When professionally installed with proper backer rods, synthetic elastomeric chinking typically lasts 20 to 30 years without cracking or detaching from the wood.
If the old mortar is structurally sound and well-anchored, we can apply bond-breaker tape and install a fresh layer of synthetic chinking over it. Loose or crumbling mortar is always removed first.
Both Perma-Chink and Sashco offer multiple natural tones ranging from light sandstone and buff to rich grays, tans, and dark browns that complement your log stain.