Flashings are one of the most important, not seen, items that we could ever talk about. Water is the most destructive element that our long term house has to defend itself from. Water and condensation almost single handedly is responsible for 90% of your new homes damage.
A great way to put it bluntly is "Fire and Water always Wins". Our job as builders is to manage water, not to water proof. Water comes from inside as well as outside and it moves through your walls on a daily basis. As a Builder, I have to recognize these different situations and adapt your home to manage these water intrusions so that they do not damage your Home. We have 2 types of water to manage, Gas Vapor, and Liquid Water.
In our part of the world Vapor moves through our walls from both directions, seasonally. Vapor moves from Hot to Cold, and from More to Less. In plain English, In the Summer months it is Hot outside and Airconditioned inside, so Vapor moves toward your nice conditioned air space inside and the reverse is true in the Winter months. An example of this is static electricity. Ever walk across the carpet and touch a light switch and think you just got electrocuted? Did it ever happen in the summer time? Well that is real life of humidity leaving your house in the Winter and coming-in in the Summer. If we try to stop it, it condensates (turns liquid) and runs down our walls somewhere that we do not want it to. So our mixed climate dictates that we let it through in vapor form and deal with it in the air and not in the wall cavity.
We should consider adding both demumidifiers and humidifiers. If you understand this we can talk about what is right for you and your budget. You should know that this is strickly a comfort issue and is not terribly hard on your house unless we cause it to condensate in the walls.
Next let's talk about "Liquid Water "