A nice elegant solution which if you don't mind I might borrow.
I do have one small observation, I notice that you have left many of your pieces touching face to face and given that the solution was to overcome a single skin wall I suspect you may get high humidity in winter, if so you run the risk of mould between the least used pieces, I would recommend that you interleave each piece with a thin sticker 5mmx5mm at 50cm intervals so as to allow air to circulate between each piece and avoid mould. If you were outside then it would be 10 or 15mm pieces. Just a thought .
PG