Going to have to find out if there 3/4 or 1- 1/2" thick.
Roofing's going to have to come off to replace the old board.
Some reasons why that last board may have rotted, lack of a drip edge, if your in a snow area lack of storm and ice shield, not enough over hang on the roofing, clogged up gutters if you have them.
I've never seen tonged and grooved beveled edge laps at HD or Lowes.
https://www.google.com/search?q=Ton...=pCRUV5TRDsLs-QGMxo6QAg#imgrc=L3k40eiiYS6fJM:
Roofing's going to have to come off to replace the old board.
Some reasons why that last board may have rotted, lack of a drip edge, if your in a snow area lack of storm and ice shield, not enough over hang on the roofing, clogged up gutters if you have them.
I've never seen tonged and grooved beveled edge laps at HD or Lowes.
https://www.google.com/search?q=Ton...=pCRUV5TRDsLs-QGMxo6QAg#imgrc=L3k40eiiYS6fJM: