Trying to figure out what caused this damage to a couple of isolated spots on joists in my attic.
It seems flaky, but it seems like it just stopped at one specific layer of the wood - as though if I scraped it off, it would look like nicely finished wood underneath. You can see in the cross-section that the damage is a pretty consistent thickness. But if I just scrape it off, how do I know whatever caused it isn't going to come back and really start to eat away at theses joist?
In a quick scan of the attic, I only found 2 locations, 1 about 16" long, the other about 10" long. The 16" is on a roof joist, and the 10" one is on the main center beam. None of the wood around it appears to be damaged, and the floor underneath these 2 spots also appears to have no evidence of damage.
Any suggestions you have are welcome. I don't really know where to start.
It appears this may be a case of all "bark" and no bite.
Remember wood comes from trees. Dimensional lumber is made by slicing trees into uniform pieces. Most of the rough edges usually get cut off. It seems a little left over bark may be present due to uneven surface of original tree trunk. Two small isolated spots in the photos indicate a couple of bad spots on the lumber. No harm, no foul.
InspectorMark
Posts: 87 | Location: OmahaNE | Registered: 26 July 2005
Sometimes outer layers of the tree have fungus that cause this, the wood may have appeared in better condition some time ago, but as it dries the natural bonding in layers of the wood becomes brittle, like dried sap. The discoloration of the wood suggests this may be the case, and the layer coming off is simply due to the drastic temp changes that occur in attics. Nothing to be concerned about in most cases this layer will be the last you see of it.
After looking back at the pics again, I agree with everyone else, in pic 8 you can even see what appears to be the trails of bark dwelling insects that are common on the surface of lumber beneath the bark. These trails are identified by the pale "pathways" on the surface, creating almost a maze effect. The only thing that throws me off is the color of your wood, has it been stained or sealed?
The 'bark' left on wood in processing is called 'wane' and should not be selected by quality builders, who hand pick the wood for your home. Mold and fungus can be killed by soaking lightly with a 50% chlorine solution in water.
Standing dead Ponderosa can still have 'Pine Bark Beetles' in the bark or just under it. Scrape a little spot and see if you have little trails under the bark - if so, use the chlorine and sleep tight.
It definately appears to be bark- if the builder was paying attention, he may have placed the joist it it's proper direction- long boards tend to be "crowned" and it just may have turned out that the bark side was left in view so the joist could be properly placed. Other than the pine beetle comment, I wouldn't worry about it at all.
