You are scheduling the cost which I assume is a property calculated via an expression.
Because you have created it as a text property, the schedule will not sum them (can't sum text) and it assumes each wall is 'unique' due to this different value in each wall - therefore they will not merge as one item in the schedule.
I am not 100% sure, but if you change you property from a text value to a number, then it may ignore that they are different values and merge them all as one surface.
Also you may need to use a surface schedule rather than an element schedule.
Barry.
One of the forum moderators.
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