How do I get more factories built in Victoria 2?

Solution 1:

There could be several reason:

• do your capitalists have any money to spend? Check your capitalist pops in the relevant regions to see if they have any free capital. If they do not you might want to reduce taxes
• it is also possible that the resources required are in scarcity locally or on the world market. Remember that locally produced resources first get offered to the leading nation of your sphere of influence (if you are in one) and on the world market higher prestige nations are offered resources before you. You might want to do manual trades to build up a national stockpile and open up the national stockpile to local trades if this is the problem.

Also I believe I read on Paradox forumns that there are some bugs in v1.1 that impinge on capitalist factory projects but you I do not specifically what they are. Future patch v1.2 should contain a fix for capitalist projects (see here) but may not apply to your problem.

Apologies if I used any misleading terms in my explanation. It's been a few weeks since I played... :-)

Solution 2:

Have more capitalist (set a national focus) and drop taxes for them, once you have enough of them and they have the money, they will start building.

Other way is to get the right party elected, in this case you can build factories yourself.