Cordwood -- Glass Bottles and the Code

So I've spoken to a local building inspector about building with cordwood in my area. He's open to the idea, and says people can submit plans for any kind of material. As long as the walls conform to energy requirements, we just need to meet State energy code (currently R-21).

We plan on a couple bottle art formations and the occasional random bottle end. Has anyone had problems with code enforcement and glass bottles? I would think they're analogous to double-pane windows, but I'm sure an inspector would disagree.

Our jurisdiction follows international building code.

Good to hear that the building inspectors are open to alternative building.
If you don't have one, either get a copy of the IBC or go to the library for one you can read and make notes from.
Bottles are not going to be analogous to double pane windows because you won't have argon or an other gas contained within the double bottles.
They will however be able to offer a higher R-value than single pane windows and that can be improved with insulation as you do the construction.

You can use the Cord wood double wall construction technique and have a minimum R-30 wall, This technique uses shorter wood sections and is easier to construct since you don't have to put any insulation medium in the middle of the chord wood wall, between layers of mortar.
The double wall method also gives you easy chases for all wiring and plumbing should you want to do that as you build. (It has been used in Upper Mich. and that original house with a wood burning stove for heat uses 2 chords for an entire winter, not bad at all).