We have a house in the Caribbean. It’s built entirely of cement block – No exterior covering, no interior covering. Just standard CMU. We want to replace the current windows, but would like to be prepared before we start pulling them out. The current windows are aluminum jalousie windows and are simply attached to the opening through the sides with Tapcons. I have no problem installing the new windows with this same fastener method – That seems to be pretty common here.
My issue is that I do not believe the openings are flashed / waterproofed. We always get rain from the same side of the house, and all of the windows on that side of the house leak profusely when it rains. I believe this is a combination of no waterproofing and improperly sloped sills (The sills are either level or tilted inward toward the house. None of them are tilted outward). So my questions I have are:
How do I fix the slope of the concrete sill? Just scrape off the top layer of paint and throw some cement down on top of what’s there, being careful to not resize my opening in the process?
What’s the best way to waterproof the opening? Since I don’t have a facade, I can’t really use a physical waterproofing membrane. I was thinking of just using Lanco White-Seal or Henri Top Coat (The same thing used on roofs here) but I’m questioning that – There must be a proper way to do this, and I’m not sure it’s that.
Is there a better way to attach the window to the opening than tapcons through the sides? Windows sold here don’t really have flanges, so I don’t know what other method you could possibly use to attach them.
Crappy Photos: https://imgur.com/a/11xwnVm