If you are replacing all the windows in the house, it will also need to meet the new 2015 VBBL requirement U-value of 1.4. Most contractors out there are clueless and doesn't know this. So if the windows that you ordered is only double glazed, you are pretty much screwed. To meet U-value of 1.4, almost all windows needs to be tripled glazed.
https://www.biv.com/article/2014/11/...ilding-bylaw-/
Any changes to your plumbing will need a plumbing permit and any changes to walls or interior layout will need a building permit.