I provide a overview training / new hire orientation that covers how the company process works and what is expected of their position. This training is completed in a video format that I created with a power-point presentation. This reviews more of the safety policy and requirements than how the actual roof is installed.
After they have been in the ropes for 90 days and are starting to get into the mix of things, they are started on learning the basics of field install.
Mock up roof at the shop is used at quarterly meetings and examples of how the roof details are measured, calculated and installed. This is used for training technical inspectors for the sales team and completing installation reviews with the installers.
Everyone is having the same issue with finding the crews to complete the work.
Cast a bigger net on the hiring pool, I did this by simply hiring more people at $14 on a 90 day period instead of $16 right off the bat for laborers. Instead of terminating 25% of the people after the 90 days I was closer to 75% but the few I did have left were already getting into field installing so I feel like I get an extra 3-4 really good people at the end of the season instead of 1 mediocre and 4 that were a waste.
Hope this helps.