The actual production rates don't match the rates outlined in the Construct building tooltips. For example, the Construct Glass Furnace tooltip says 0.5 Glass, but once built it shows 0.6 when hovering over the actual building and shows 0.6 in the Resource Rate column. This seems to be the case for all production buildings except for ones that are harvesting from deposits. I've also verified, by hovering over the Resource Rate, that there's no additional modifiers affecting the rate.