Help Creating Bill of Materials Using Building Materials

[Anonymous]

Hello All,

I have been a long time Archicad user and fan of the forum, and this is my first post. I am experimenting with Schedules to create a bill of quantities using expressions applied to materials. I want this to be able to react live in Archicad 23 without extracting information to excel or similar. I have created formulas that can take unit costs and calculate total costs, however I have found that this formula(cost(m2) x surface area (m2)) works with whole elements (walls, slabs, roofs etc) but doesn't seem to work when applied to Building Materials. As walls are often composites made of different Building materials it would be ideal to add unit costs to the Building Material (which is possible now with A23) and not the composition of the element (wall, slab, roof etc). However like I mentioned, the formula will not calculate the overall Building Material cost (cost(m2) x surface area (m2)). Does anyone know what I can do to calculate costs of Building Materials live in a schedule? or any other useful formulas for Archicad schedules?

[poco2013]

I suspect that the formula you've shown is not the one your actually using. However, if it is, you are multiplying m2 x m2 which gives area to the fourth power. To get cost, you must remove (cancel out) the area units from your calculation to get a raw number.

[Anonymous]

Apologies, for cost I meant to type $/m2 and not m2.

The formula that I am using is: CONCAT ( "$", STRCALCUNIT ( {Property:General Parameters/Surface Area} * {Property:QUANTYITY AND ESTIMATING/Cost (m2)} ) )

The formula works, but only for elements (their surfaces) and for some reason is not working for Building Materials despite being able to apply the same properties (which are the same expressions as are working for the elements).

[poco2013]

You might want to double check that the wall structure type (basic,compound,complex) matches the building material type. Other than that, there is still too little info here to trouble shoot.