I have seen from the discussion on the Supermarket thread http://forums.civfanatics.com/showthread.php?t=69580 that it isn't possible to have more than one Granary-type building working in a city. But I have a related question. If I create several Granary-type buildings in the game, could any of them be built in a city for the effect (with only one working per city), or would the game not allow the additional Granary-type buildings to work at all?

I want to make 4 Granaries in my game, each requiring one of the following strategic resources: Wheat, Corn, Barley, or Rice. My desired effect is that you would need a strategic resource to build a Granary (a grain, go figure), but I don't just want a generic "grains" resource.

I think you would be able to build all of them, and all give the effect, and if you got more then one in a city, everyone except for one would have no effect

Thanks! I could find it out by testing, but if someone else knew, I'd rather know first and then implement it. Much obliged, Kenta'arka. And thank you for your building files, I've been using some.

I believe that multiple granary-type buildings could be easily do-able, if you treated them in the same way that the standard game treats Power Plants: building one type will replace any other already in the city (since multiple would have no positive effects). So, if the mod you're making DOESN'T have power plants, OR perhaps just one type of power plant, OR you're fine with stacking multiple power plants in a city (not sure if the effects would stack, you'd have to try and see), THEN: you can mark the flag that says "Replace other improvements w/ this flag marked" (or some such thing) for all you Granary-type buildings and make sure to unmark it for all power plants.

And that's my 2 cents. ;)

Yes, it is possible to stack power plants, and it is also realistic. The main argument against it that I see is that it would send the city's production skyrocketing. To counter this effect, it would be more balancing to increase all building and unit costs as more plants become available for building. The only problem is that the AI doesnt' understand the need for building all power plants available before embarking on the construction of a costly-but-vitally-important building. This itself is unbalancing, since the human players make the choice to increase production first; while the AI gets bogged down in lengthy building projects. At least, that's what I've seen in my mod.

All that said, I think I would prefer to limit the number of power plants per city to one, and see if I can get the game to allow the first granary built in a city (of whatever type) to work.