Step 1 s Dig soil away farm the rotted post. «: inspect the splash board for decay, it may need to be. replaced = Brace the rotted post by fastening & support beam underpart truss and lifting with an adequate sized Bette jack: * Make sure the brace and jack assembly are installed securely and safely. Tepid = Saw off the rotted post approximately 3" below the top. of tha splash board. s Her move the rotted section of the post.