How strong is finger jointed timber?

The strength of finger-jointed timber varies, but its mean strength is approximately 80% of the strength of unjointed timber.

Here's a breakdown of finger-jointed timber strength:

• Mean Strength: Approximately 80% of unjointed timber.
• 5-Percentiles: The 5-percentiles vary between 9 and 20 MPa (MegaPascals)

The 5-percentile values are important in structural design because they represent the lower bound of strength. The coefficient of variation, which is the ratio of the standard deviation to the mean, affects the 5-percentile values. In finger-jointed timber, the 5-percentiles differ less than the mean strength due to a smaller coefficient of variation.