According to the North Carolina Cooperative Extension, noticeable signs of termite damage to wood can take an average of 3 to 8 years to appear, depending on the width of the wood.
When you tap on wood that has been damaged by termites, the wood will sound hollow. The most effective way to check for termite damage using this sign is to tap the wood with the handle of a screwdriver or a hammer.
If the wood is painted and you notice the paint looks like it is buckling, you may have termite damage. Upon closer inspection, such as with a magnifying glass, you may notice pin holes in the paint.
As termites chew through wood, they make tunnels using a combination of feces, saliva and soil. This may look like a line of dirt on the wood, and, in some cases, you may see small wings in the area.
You may notice splinters of wood around the house, which is a sign of termite damage. This is especially true if the termites are chewing through hardwood floors.