Our first real scheduling delay.
The supplier delivered the wrong under-slab insulation; XPS instead of EPS.
Supplier doesn't have what we need on hand, so it pushes our slab pour out a week.
We want to use EPS to avoid using a nasty chemical blowing agent that is used in the XPS manufacture. But since the XPS was onsite, we had a tough choice to make; do we use it instead? What is the negative value compared to the positive value of increased R-value and years of energy savings? Hard position to be in.
Turns out the supplier was charging us a couple grand more for the XPS, so it made sticking to our morals easy. If only the market always rewarded doing the right thing...