EIFS and WRB questions
We are at the design phase of our new home. We live in a Nicosia, Cyprus and we enjoy a Mediterranean climate with mild winters and hot summers with only a few inches of rain per year, and relative long sunny periods between wetting events (rain). Our design calls for large overhangs (4-5 feet) around most of the building, mainly for shading purposes during the summer.
Most of the construction in our country (95% if not more) is done with reinforced concrete structural members and brick walls, however we are planning of using I-beams for structural members and light gauge steel for wall framing purposes with glass-mat or cement board sheathing. Now the majority of insulation is done with a face sealed EIFS (EPS and XPS) on traditional construction and since our steel members will probably reduce the value of our cavity insulation to half its name value I am thinking that the best insulation method for our case is also EIFS. However, having read here that the face sealed EIFS is not a good idea with a wall that cannot store moisture has raised concerns. So my questions are the following:
1. Should I be worried or even avoid using face-sealed EIFS, even if it is hard to get a WRB installed? (House wrap is a new thing here and liquid WRBs, which I really like from what I read, are virtually unheard of). I am thinking that I might not be in such a risk given our weather.
2. Almost all systems of drained EIFS I have read about, call for drainage channels between the WRB and the insulation. Given that the insulation is not in full contact with the wall does this change its effective R-value?
3. All of the windows I have seen installed are held in place via screws through the sill, jambs and head of the casement. Are flashing tapes and liquid applied flashing products self healing if perforated by screws or is there a certain way that you need to treat these perforations to keep the waterproofing of the flashing.
4. What would be the best/easiest way to air seal the building envelope in my case if I use rockwool for the external insulation and synthetic stucco as a finish.
Sorry for the long post.
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