In this blog post you will find some helpful Formulas for schedules in Revit.

Calculating Costs for Concrete
Choose the Floors category, add the scheduled fields Cost and Volume from the list of available fields to begin calculating the Cost for Materials.

Concrete is measured by Cubic Yards. So you need to convert the volume of concrete you have into the number of Cubic Yards needed using the formula:

Cubic Yards Needed = Volume / 27

 To determine the Total Cost of Slab Concrete, you will need a second calculated value using the formula:

Total Cost of Slab Concrete = Cubic Yards Needed * Cost

After you have created the Schedule using these custom formulas, enter Cost into your Schedule and Revit will calculate the Total Cost of Slab Concrete using the custom formulas you created.

Calculating Costs for Walls
Choose  the Walls category. From the list of available fields, add the Family and Type field (if you have more than one type of wall), Length and Cost to your scheduled fields. To calculate the Cost of Material, use the following formula:

Cost of Material = Length * (Cost) / 1

After you have added the custom formula above to your Schedule, enter Cost and Revit will calculate the Cost of Material using the custom formula you created.

Calculating Costs for Roofs
A Square is calculated as:

1 Square = Area of Roof / 100 sq ft

To calculate the cost of the roof, first choose the Roofs category and, using the formula above, select Area and Cost from the list of available fields. Then, create your Calculated Value called Square. With Square calculated, you can now move on to determine Cost of Roof System, which is defined as:

Cost of Roof System = Square * Cost

After you have added the custom formula above to your Schedule, enter Cost and Revit will calculate the Cost of Roof System using the custom formulas you created.