Data Conversion

[Down2Earth50]

I am trying to create a formula to convert data in C1 to something else in C2, for example. I am working with wood/board lengths. If in C1 I enter 2 x 4 x 91.5", I want the same data entered into C2 but converted to 2 x 4 x 8’ or 2 x 4 x 96”. C1 will contain an actual measured length needed for a project and C2 will convert to a length needed to be purchased based on purchasable lengths being 8’, 10’, 12’, 14’, 16', 20’, etc.. Example: This formula in C2 =LEFT(C1,8) & (ROUNDUP(MID(C1,8,4)/12,0)). The issue I am having is that when the string entered in C1 becomes longer or shorter the formula does not work. The other issue is that if C1 contains 2 x 4 x 8’-5”, C2 has to convert to 2 x 4 x 10’ and so on. So my attempt to add to the formula is =IF(MID(C9,9,2)< 96,8,10) but I can't figure out how to intertwine this formula into the 1st formula. Then there is the issue of when C1 is 4 x 8 x ½” and so on. Or its 3’-5”x 3’-5” x ½”. The question is, am I even using the correct formula for what I want to accomplish? Can anyone assist me with this?