Recent window install

[mbgo60]

Live in North Georgia and recently had new double pane, double hung vinyl windows installed. They are the pocket windows so after the original double pane wood windows were removed the new windows were installed from the outside.
I question the install method. Once the new windows were placed in the openings left from the old windows, screws were installed thru the window frame. A bead of caulk was applied at the joint of the window and opening on the inside. On the outside an aluminum cover was cut and formed and placed over the window frame and house trim. The aluminum is about .020" thick and held in place by a couple nails and a bead of caulk around the top and bottom edges. The home is wood-framed with the cement siding.
I was only able to observe one window installation before the aluminum cover was installed and would say there was about a 1/8" to 1/4" gap between the window frame and opening. It was explained to me that this gap is 'dead air space' and acts as an insulator. I understand the 'dead air space' concept but the temperature of this air is going to be whatever the outside temp is since it's covered by a .020" thick piece of aluminum (a good thermal conductor).
This means, other than the inside flat surface, the entire window is subjected to the outside temperature.
The windows feel drafty (worse than the originals) but I cannot verify a draft with a lighter.
What do you guys think?

Thanks.

[toddinmn]

This method is common, execution is key. Some pictures would help to evaluate it further.
What brand and model of window did they use?
The gap should have been foamed in.

[Delaware Mike]

You will need a "tolerance" space around the wood opening to the size of the window to be able to square it and have all of the margin/reveals be uniform between the sashes to the frames. If it were super tightly measured with no spacing, the installers would have to lubricate and beat it into position with a clown hammer and the thing wouldn't work or possibly even lock. We never see perfectly square openings. That spacing gets filled with insulation preferably low-expansion spray foam. I've not heard a window pro under 100-years of age refer to not filling those voids as "dead air" is an insulator. Most pros take off .250" to .375" on the make size of a replacement window to opening. With new construction we take off more.

[WindowsDirectCinci]

Im with the others, the spacing between the window and frame is normal and expected. The only thing is if the gap is on the smaller side of the spectrum 1/8" foam insulation isn't really a good option imo as I prefer 1/4"-3/8" void for foam. Fiberglass insulation or filling the void with caulk would be preferred over just air. Just an air space wouldn't be acceptable to me. I'd rather stuff napkins in the voids than just leave air space.

[mbgo60]

Thanks for the replies.
When I asked the installer why he didn't fill the gaps he put me on the phone with his supervisor who said 'we have been installing windows for 30 years that way without any issues.' So, yeah.
They are Simonton windows.
I was only able to get a photo of one window after it was installed but before the aluminum cover was attached.
See pics.
The gap appears largest on the middle to upper left side. There is a slope on the bottom of the opening to allow rain water to drain.

[Windows on Washington]

Is that "finished"?

I can see what they maybe didn't want to cap with the shutter hinges, but you can still install some molding or something to cover that. And it should be sealed.

[HomeSealed]

All looks and sounds pretty normal outside of the fact that they didn't seem to insulate or seal around the perimeter. Conventionally that gap would be foamed, caulked (if too small for foam), or have some loose fiberglass stuffed in there. Is it possible that they caulked it prior to capping?

The important thing here is sealing to prevent air leakage. Even when foam is used it still doesn't entirely FILL the full depth of that space.