Proper Caulk JoinT Design for Log Home Chinking
Proper Joint Design
- Round backer rod is best, especially when substantial movement is expected, which means with new logs orāgreenā logs.
- Ideally, when caulking and chinking between log courses, the caulking line should be no less than 15% of the log width. For example, with 10″ diameter logs, a chink joint should be about 1-1/2″ wide. If you choose to apply a smaller bead, expect more repairs.
- Ideal sealant depth is half of the joint width, but no less than ¼”, nor more than ½ā.

Ā Steps to Proper Joint Design
- A stained surface: Caulking and chinking actually adhere better to a stained surface than bare wood, so stain with a compatible stain first. If you arenāt sure if your product is compatible, contact us first.
- A clean surface: If your surface is already stained, make sure itās clean, too. Remove all dirt, dust, oils, old caulking, peeling stain, bird poo, pollen, etc. etc. If caulk is applied over any of these things, it wonāt stick properly.
- Insert a bond breaker: Caulk works like a rubber band. It stretches really well when pulled from just 2 sides. Pull from 3 and it wonāt go as far and will break more quickly. A bond breaker, in the form of backer rod or clear packing tape, ensures you have just two points of adhesion – on the sides of the joint. You donāt want the caulk to stick to the backside of the joint.
- Tool to an hourglass shape: Round backer rod helps you accomplish this pretty easily. The caulk should be slightly (yes, only slightly) thinner at the center where it needs to stretch, slightly thicker and wider at the edges for good adhesion.
- TIP: Donāt wipe off more than you put on! A light touch with a slightly damp foam brush or a trowel will do the trick. You donāt want to starve the joint of caulk, either.Ā