Insulating around new windows/top flashing

[SolarAndWood]

I have 30 metal clad wood windows that have just been in with 4 screws and fiberglass stuffed around them. I have heard warnings about using even the non-expanding foam for around windows? Is this nonsense or is there some concern here?

My wall buildup is 2x6-3/4 cdx-felt-1"XPS-Tyvek-vertical shiplap. Currently the wall is just plywood. The windows have to come out either way as part of the process so all options are open.

On the flashing, are the newer products like Protecto Wrap good enough that I don't need to worry about tin over the windows? The house also has big overhangs so there isn't going to be a large volume of water running down the outside of the wall anyway. Or, is it one of those things that you do it anyway because it is a lot easier to do now than after you finish and regret not doing it?

 

[woodsmaster]

I do a lot of windows and doors and use the window and door foam with no problems. A nice beed of silicone under the nail flange is all thats really needed on the outside but the protecto wrap and a drip cap make good insurance. With a large overhang I would probably skip the drip cap.

 

[Huskyforlife]

In my opinion Protecto Wrap is sufficient, assuming you are siding over it and it will not be broken down by the sun/UV rays. Foam is much better than fiberglass for sealing around the window, just make sure to use the non-expanding stuff and go easy with it. Good luck and take your time, properly shimming and installing a window takes a while, that's why I would never hire the Home Depot $99 install contractor that throws the windows in in 20 minutes (and all out of square).

 

[fishingpol]

x1. Window and door foam are minimally expanding and softer when set than the great stuff products out there. I use Grace ice and water shield sold in narrow rolls around window perimeter before installing the window. Silicone as mentioned above. You can put a piece of wrap over the top nailing flange once nailed in, but with large overhang, probably not needed.

 

[semipro]

I'd definitely use foam and I'd definitely use the low-expanding type. If you're really concerned about the windows bowing in perhaps you could install a few carefully cut 2x4s horizontally inside them to prevent movement.

Proper installation of windows requires that the opening be flashed correctly before the window is installed. If the windows have nailing flanges some may think this is overkill but I don't think you can do enough to prevent water damage, especially if you are using a vertical orientation on siding, which, in theory, would present less of a barrier to water getting to the water-shield beneath. Fine Home building magazine has some good articles on this including the one below.

http://www.finehomebuilding.com/how-to/install-replacement-windows-and-flashing-correctly.aspx

 

[SolarAndWood]

Thanks guys. That article was great Semipro. Looks like I am going to spend most of my free time for the foreseeable future installing windows.

 

[gpcollen1]

Thanks guys. That article was great Semipro. Looks like I am going to spend most of my free time for the foreseeable future installing windows.

I just got done with 2 windows and 2 sliders. I did it pretty much just like this. Some of my friends said why the spray foam, why the tape, why why why? Of course I told them why...

That window and door spray foam is awesome. There is no way that the fiberglass can touch it. It does suck to have to trim it once you are done but it is worth it. People just don't realize how easy it is to get water or air leaking into your house.

Good Luck

 

[billb3]

Even though the low expanding foam is much improved I developed a habit of spraying about 9 inches of foam, then skipping 6 inches, repeating all the way around and coming back the next day to fill in the gaps.
Didn't have problems with bowing or bending anything that way.

 

[flyingcow]

Slowly been taking off window trim and removing all old F/G around windows and replacing with window and door foam. Amazing difference. If i ever get a chance to build a house again, no F/G. Foam only throughout.

 

[SolarAndWood]

I am pretty sold on foam. Might use this product from a local company for the stud bays...

http://www.airkrete.com/

But, the DIY foam kits will probably be the way i go though as I will probably only be able to do a section of the house at a time. I'm looking forward to eventually having a foot of foam in the ceiling, 5.5 inches in the stud bays and the inch of XPS I am installing under the siding outside the sheathing. Should significantly reduce my wood consumption.