That is Oriented Strand Board (OSB), typically used for sheathing. Looks like it has been used exposed to weather, which is not its intended use. There is no reasonable repair for that, other than r ... read more
Check out this "How It's Made Video" and see for yourself:
https://youtu.be/LuxGDH9KVLM
James Hardie Siding (i.e. Hardieplank) is the best exterior cladding material (outside of true masonry) on the ... read more