Window Installation 101- Step 2

I have found that different products stand up under pressure in different ways. Some products in the construction industry have been around for 100 years & longer, while some are still under development. As a general rule, I opt for good-old-fashioned-tried-&-true things. Window flashing is an area that has changed almost daily since the advent of "double-paned aluminum" windows w/an integrated installation fin. This has made product knowledge invaluable, & difficult to stay on top of, but I try. Basically I have found the old saying: "Everything is not created equal" to be true. As a general rule, you also get what you pay for. The products I am showing aren't the only ones on the market. I even know of a couple that might out-perform, but the Fortifiber line is among the best @ innovation & quality, while remaining readily available and affordable.

Caulking is placed @ the bottom corners (a healthy bead @ approximately 1/4"). I choose Moistop here and a couple other places due to it's excellent adhesion to vinyl windows & other flashing materials.

Then, place the corner shields @ the bottom corners. These are another product that I believe is money well spent. Again, they

are manufactured by Fortifiber.

Next, place a strip of at least 6" butyl based flashing membrane. I like the FortiFlash, but several manufacturers make quality products. I look for good flexibility & adhesion. Some other options are: BlueSkin, Grace, & WetFlash. Make sure that the inside will wrap onto the flat portion of the sill past where the inside of the window will be (if you keep it in 2" or more, it should be adequate.

Continue applying the flashing membrane. The idea, with all exterior weather-proofing systems, is "shingling". Think of bird feathers or fish scales. Always overlay & work from the bottom up. The outer-most layer will be @ the top, always. Whether you are laying roof shingles, horizontal plank siding, or flashing in a window. So, think like water & layer things starting at the bottom.

The pictures should give a good idea of what the product will look like at the stage we are at. If it seems redundant, complicated, or over-technical; it is. But that is what keeps the weather were it should stay, out-side.

Next: Actually Installing the Window!