Anyone know what is needed to trigger the third hut? I have 2 huts at max population and seem to be stuck. I can't do any more puzzles because I don't have the right god powers. But, I can't get more energy because I need to increase my population (which I can't without another hut). I am slowly converting blue heathens but they are all surrounded by red and yellow ones so it is hard to get them alone. Help!

As in VV3 and VV4, you will need to attain Level 3 of construction tech. If you click on the "?" for each technology on the Tech screen, you will see what each of them provides to your tribe.

Thanks. I looked through all those but somehow missed it.