I am considering making my own ceramic roofing tiles from the abundant clay in my area. My sister makes her living as a ceramic sculptor, so I have access to several options for large kilns, as well as a pile of fire brick large enough to make a custom wood burning kiln for this project. We are trying to keep our build around 1000 square feet, so we would need about 12 square (1200 sf) of tiles. This would equal out to about 1200 Spanish style "S" shaped tiles, or about 2000 mission barrel style tiles. Making an average of 30 tiles a week in my spare time, I could complete this project in a year, although I expect that I could do these in 100-200 piece batches and finish much faster. I am a letterpress printer by trade, so I am used to slow repetitive production, and wouldn't mind putting in 4-5 hours at a time to make these. The guys in the videos below make a tile in about a minute and a half. If I can manage 3 minutes per tile I would yield 80-100 pieces in a 4-5 hour workday. Honestly, I think that I could manage a Spanish tile in 2 minutes, which would mean 40 hours of labor for 1200 tiles. I anticipate spending 20 hours harvesting clay, 20 hours firing, and 20 hours experimenting, or 100 hours total. If I pay myself $15 an hour, this is only $1,500 of labor, and since I have no materials cost, the costs of this process should come in around the same as buying asphalt shingles from Lowes.
I am in the process of designing and developing my molds, and once I have them made I will begin testing tiles. I plan to harvest clay from several local sources and make a handful of tiles from each. With these I will do my best to conduct stress tests, impact tests, and permeability tests. I also want to play with some additives to help insulation values and decrease weight. As my experiments come to fruition I will try my best to keep you posted. I would appreciate any input, insight or ideas that you have to offer in the meantime.
For this house, I will undoubtedly be using a mix of hand harvested / handmade and store bought products, but it is my dream to one day make a home out of nothing but what I can harvest and build from the land that my home is on. Sadly, building codes in my area wouldn't let me live in such a house, but that is a rant for another post.