I am trying to update my 20 year old that was originally built with the house. For starters, I tried replacing two joists. There are two beams that are holding the joists (one in the middle and one in front). My issue that is, when I sit the two new joists, it does sit/rest on the front beam but not in the middle beam. I do need to shim it. My question - is it okay to shim ALL joist to beam connections if I decide to replace more joists? or this is only happening because my PT 2X8X16 is really bowed and I need to try to get new one? If somebody can chime in that would be great! Thank you in advance.