This is a direct result of using the petroleum oil paint or acrylic paint. These modern types of paint will trap the moisture in the wood and rot the wood from the inside.

It is interesting to realize that this type of deck designs have been around for 100’s of years but it appear that there was no major problems until the petroleum paint was started to be used. This type of damage is directly linked to the type of paint. It has nothing to do with the quality of the wood. If purified linseed oil paint had been used, this porch would have been in perfect condition today.