The development of cracks in wood, known throughout the industry as “checking,” can be quite upsetting to unsuspecting home and business owners. Whether these checks appear in a wood deck, floor, or the large supporting timbers in a timber frame structure, they can leave customers feeling dissatisfied or even downright angry. So what can be done about checking? In this final article in our series (see Part 1 & 2), we’ll take a look at a few tips for mitigating the impact of checking as well as a few other helpful pointers for dealing with checks in your timbers.
Are There Any Solutions to Checking Besides Kerfing?
As we mentioned in the previous article, kerfing is an ancient technique that was developed to help prevent major checking in wood. It’s done by sawing one surface before the wood begins to dry. But since most lumber dealers don’t get the boards fresh from the sawmill in time to kerf them, it’s not really practical a majority of the time.
So what else can be done to prevent checking? Another technique that can help keep your wood as check-free as possible is simply sealing the ends of the timbers. You can also try storing them in the shade until they’re sold and moved to the worksite. Once they’re at the worksite, they can still be kept in the shade until they’re ready to install. Keep in mind, however, that if they are installed in direct sunlight, such as on a deck or in a room with big windows, the lumber can still check months and years after application.
Are Checks in Lumber Permanent?
Because wood is an organic product, it will continue to move the entire time it’s in use. This isn’t a bad thing. Checks will open up and close. New checks will open up and then close later. It’s a continual process that happens based on a variety of environmental factors. It boils down to tension that builds up due to the retaining and releasing of moisture in the wood. Lumber that’s used in outdoor applications is especially susceptible to checking.
Should You Try to Put Some Sort of Filler in the Checks?
Someone who is inexperienced with wood and doesn’t realize that checking won’t harm the wood’s structural integrity may decide to try to fill in the checks they see starting to open up in their timbers. This is definitely not a good idea. Whether you use epoxy or some other filling substance to try to plug up these cracks, it’s not going to work. It can actually interfere with the process of your wood naturally gaining or losing moisture in its outer layers. Checks that opened up and get filled won’t be able to close properly when the moisture content changes. This misguided attempt to fix the problem will actually do more harm than good in the long run.
Should Lumber Dealers Educate Customers About Checking?
By all means, yes, they should. That way a customer won’t come into the lumber yard irate and thinking they were sold defective wood when their large timber deck or floor begins to crack and pop. Instead, they’ll understand why it’s happening and have peace of mind knowing that it’s a natural response of healthy wood to changes in moisture content. Checking is nothing to worry about, and it can even add charm and character to a wooden deck, floor, or structure.
