You could try this Python script to see if it works Please note this has been written for the metric system, so if you’re in the US it will be a little different.
import clr
clr.AddReference("RevitServices")
import RevitServices
from RevitServices.Persistence import DocumentManager
from RevitServices.Transactions import TransactionManager
doc = DocumentManager.Instance.CurrentDBDocument
dimensions = UnwrapElement(IN[0])
text = IN[1]
value = IN[2]
TransactionManager.Instance.EnsureInTransaction(doc)
results = []
for dim in dimensions:
numOfSegs = dim.NumberOfSegments
if numOfSegs > 0:
for num in range(numOfSegs):
seg = dim.Segments.Item[num]
if seg.Value * 304.8 > value:
dim.Segments[num].Above = str(text)
results.append(dim)
else:
if dim.Value * 304.8 > value:
dim.Above = str(text)
results.append(dim)
TransactionManager.Instance.TransactionTaskDone()
OUT = results
It will set the chosen text above the dimension - but only if the dimension, or dimension segment, is greater than your chosen value