Surface Preparation

Before applying chinking, the surface of the logs/wood must be clean of all dirt, oils, pollen, sawdust or any other loose material so that the chinking can achieve good adhesion. The surface temperature should not be above 90ºF or below 40ºF. If the logs are too cold the pores of the wood tighten and do not allow proper wetting out of the surface; if the logs are too hot the liquid in the chinking can evaporate too quickly, causing lack of adhesion or blisters.


If you are staining your wood, we recommend that you apply the stain before applying the chinking. Allow the stain to cure for at least 3 to 4 weeks before applying chinking (or see the application instructions supplied by the stain manufacturer). Some stains contain waxes that can interfere with adhesion so you will need to make sure the chinking and stain are compatible before chinking. Oily stains can also affect adhesion negatively so it is important that they be completely cured before chinking. Doing a small test application before doing the entire chinking job can save a lot of headaches later.

Remember also that newly put-up logs will settle quite a bit over the first year or so and, depending on the moisture content of the logs, they will also shrink to varying degrees as they release this moisture. Do not chink until you have an understanding of your particular home in these regards.


Our chinking is packaged in various size containers, from 5-gallon pails down to 30 oz. tubes, to facilitate different methods of application. For larger jobs, 5-gallon pails are the most economical and they can be resealed to minimize waste. Our chinking can be applied with a trowel directly out of the pail, or with a grout bag or a bulk loading caulk gun. There are even chink pumps, which are fairly costly, for those doing a lot of chinking.

Apply the chinking down the middle section of the area to be chinked for starters, taking care to apply only as much chinking as you can reasonably tool before it begins to skin over, then begin tooling your chinking to achieve the finish you desire and to smooth it up against the edges of the chink joint.

In general, Vimasco chinkings should be applied between 1/4″ and 1/2″ wet thickness; sagging or running can occur if the chinking is applied too thick. You will find that Vimasco chinkings, which are safe, non hazardous latex emulsions, are easy to work with and, once you have a little experience, applying chinking is not really much more difficult than doing your own paint job.

Our chinkings also incorporate modern latex formulation technology and are much easier to apply and longer lasting and maintenance-free than the old mortar chinkings that were used in years past.

Bond Breaker Tapes and Backer Rods

Many chinking applications will require either a “bond breaker” tape or backer rod underneath the chinking. If there is a gap between the logs/timber that needs to be filled in, use a backer rod, which is basically a piece of foam insulation, to fill in the space. Backer rod comes in various sizes and shapes and should be selected depending on the type of gap being filled. It is available in closed cell and open cell foams, you can select the one most suitable for your application.

Closed cell is firmer and repels water, Manufacturers of Quality VIMASCO CORPORATION Chinkings Since 1985 P.O. Box 516 * Nitro * W.Va. 25143 (304) 755-3328 or (800) 624-8288 8/03 so is normally recommended for outside jobs. Open cell is softer and breathable and allows for a faster cure, but it will absorb water.

Smaller joints between the logs which are too small to fill with backer rod should be covered with a mylar faced, or similar type, tape. The purpose of this “bond breaker” is to provide a surface to which the chinking will not bond entirely. This area enables the chinking to release slightly from the bond breaker surface when expansion/contraction or movement occurs, enabling the chinking to stretch and move to more effectively resist cracking or delamination from the wood. Experienced chinkers will all confirm that this bond breaker can be a critical part of a successful and long-lasting chink job.


There are a number of different chinking tools, including spatulas (rubber, teflon, etc.), paintbrushes, putty knives, and trowels. Use whatever you are most comfortable using and select the appropriate size tool for your chink joint.

It is not necessary to spray Vimasco chinkings with water to make them easy to tool, however we find that a slightly damp polyethylene brush will give you the best possible finish and make this step a lot easier. Finish tooling this section of your chinking completely before you go on to another section otherwise it can set up and become difficult to change.

You will note that tooling is easier on a stained surface than it is on an unstained surface. Some chinkers use tape to facilitate a clean, straight chink line.


Water may be used for clean up of hands, surface and equipment. Make sure to clean up while the chinking is still wet, otherwise cleanup is more difficult. Make sure to follow all state and local regulations on clean up and disposal, as you would with any latex paint.


Blisters can form when moisture from the chinking or from an external source accumulates in voids beneath the chinking and the heat draws the moisture to the surface causing a blister. Most blisters occur early in the curing process.

To avoid this, try not to chink in direct sunlight or use a tarp to keep the sunlight off the chinking during application and curing. If this is not possible, keep an eye on the chinking for the first 24 to 72 hours. If a blister pops up, puncture a hole in the middle of it (releasing the trapped air) and push it gently back into place. After 3 or 4 days repair the blister by applying a small amount of chinking in the hole.

There are other factors you should watch for in order to minimize the possibility of blistering. These include: cracks in the backer rod or in the wood where water might enter, air bubbles created in the application process or caused by out-gassing of the backer rod, and accumulated sap on the logs.

Curing & Maintenance

After application the chinking will be dry to the touch in 24 to 48 hours, depending on the weather conditions, but will likely not be cured all the way through for another 2 to 4 weeks. In colder climates, or areas with extreme weather changes, curing can take longer.

Make sure the chinking is not subjected to rain or freezing temperatures for at least the first 48 hours, and observe it during the first few weeks for any signs of curing problems.

Vimasco chinkings are designed to last for many years without replacement or repair, but, as with any field applied product, conditions can vary and routine inspection and repair where necessary will ensure a long-lasting and attractive chink application. The quality of our products is something we have taken seriously for almost 50 years. Call us with any questions about your chinking at (800) 624-8288.