When mortaring bottle ends for a house in northern climes, it is best to not use too many and have the precious heat escape. However, when doing a chapel or an outdoor wall the imagination can run wild. Here is an outstanding example at the Arlie Chapel in North Carolina. www.cordwoodconstruction.org
Bottle ends make for a stunning stained glass statement at the Towers Earthship "build." This photo is courtesy of the Earthship website http://earthship.com/Designs/earthship-village-ecologies. To learn to do this in a cordwood wall without having to cut the bottles, go to www.cordwoodconstruction.org and click on What's New?