Enlarge/Reduce on a wall or roof

[kbob]

My question is simple: would enlarge reduce work on a part of a building like a wall or roof? A door is given in the DMG (I believe) as an object. That is part of a building. If a wall or roof is not, what about a large stone in the wall or a panel on the roof?
I ask cuz in a game I played in recently, we came across a steeple to a temple sticking out of a body of water. I was playing a wizard and casted E/R to shrink the steeple. The DM allowed it and we flew into the Temple. Could this be allowed as per rules? They seem a bit foggy in the description. An object according to the DMG is not building or something with a lot of parts like a vehicle. But what about part of the building, like a steeple in the example above? Or an axle to a stage coach?

[Chronos]

I have a hunch that, if you were to ask the devs, they'd tell you "You can't shrink a building, because it's not an object; it's a whole bunch of separate objects. And you can't shrink a part of a building, because it's not a whole object, just a part of the whole building, which is an object."

Which means, yeah, ask your DM, because the rules aren't clear at all.

[stoutstien]

And my head canon, enlarge/reduce is a relatively simple magical principle, the issue comes into applying it. So if somebody wants to enlarge or reduce a object that is detached then it's simple and there's no problem but the more questionable the item is as far as being it's own object the harder it is to get the results that you want. The caster can either up cast or make a ability check to get the desired results.

I've also remodeled the saving throw effect as well.

[firelistener]

Since the range of the spell is 30 feet and the largest size creature, gargantuan, is ruled as 20x20 feet, then I would limit objects to anything completely within a 30 foot range. So a small cottage would probably be a valid target, but a large temple would not be. I would also lean towards letting the wizard target a building as a whole, not single parts of a structure. To me, this is similar to how you must target a creature and it affects everything they have on them.

[Damon_Tor]

It's up to your DM, there's not much more to say about it except how we rule things. Generally my rule of thumb is this: if an infinitely strong entity took ahold of something and moved it around, whatever comes with it in a single rigid mass is "one object". For a stone building, this would usually mean each stone, or maybe a clump of a few stones, is its own object because mortar just isn't strong enough to keep a stone wall "hanging" together if you grab one part of it and lift it up. It keeps the stones stacked nicely, but it can't hold it together if a giant game and tried to pick up the wall.

Also, anything engineered to move independently even if affixed in some way (wheels, doors, the rigging of a ship, the cork in a bottle) are separate objects and treated as such by the spell. And loose gasses and liquids are never objects or parts of objects, so a bottle of wine is three things, the bottle (one object) the cork (a second object) and the wine (a fluid).