Insulation around windows ?

[MossRoad]

Don't pack insulation around windows. It should be put in so that it's not compressed. If you pack it, the insulation value will be greatly reduced.

 

[ROUSTABOUT]

No this house did not originally have insulation inside the walls but about 30 years ago I blew insulation into the walls and ceiling, obviously that doesn’t work very well but it’s better than nothing.

Always a pain with fire blocks.

 

[jaxs]

Since you say outside work is finished it's probably too late on this job but wrap windows on next job before installing siding and trim. That not only seals out air but prevents water soaking into foam then rotting surrounding wood.
Oh BTW USE FOAM SPECED FOR WINDOWS AND DOORS.

 

[timbatrader]

I have recently put windows into a new build I push a PEF foam rod into the back of the gap as a back stop before putting the foam in I found the cans don't work on cold days so wait until midday on a sunny day if in winter another tip is that what sets off the foaming reaction is contact with the moisture in the air or suroundings so spray water around the windows before foaming which makes the foam expand more predictably therefore easier to avoid over foaming with it expanding where you don't want it

 

[Have tractor did travel]

Don't pack insulation around windows. It should be put in so that it's not compressed. If you pack it, the insulation value will be greatly reduced.

From R-value (insulation) - Wikipedia
"Squashing two layers of batting into the thickness intended for one layer will increase but not double the R-value. (In other words, compressing a fiberglass batt decreases the R-value of the batt but increases the R-value per inch.)"
In other words, packing in insulation, as I suggested, has diminishing returns, but more R value is still obtained. Since insulation is cheap, and you're only doing around windows (not using much), I still recommend you seal where you can, and pack where you can, and the two are not mutually exclusive.

 

[oosik]

I built my PanAbode cedar timber home here in 1982. Used spray can foam around the two exterior doors and all the windows. The house is still sealed up - tight as a drum.

 

[IH2424]

Installed all 12 new windows in my 86 years old house. The outside work is mostly done but now I need to finish the inside work, need to insulate the small space around the windows and am wondering about using that spray foam type insulation that comes in aerosol cans , have you ever used the stuff and if you did how do you like it ? Maybe I’d be better off just using regular fiberglass insulation ? Thanks for your help.

Another vote for the Window and Door version of Great Stuff spray foam. I have replaced almost all the windows in our 100 year old farm house over the past 20 years and used it on every one. I did make the mistake of starting with the wrong foam and did spring one of the casings - i had to take the trim off and cut out the foam, then put in the right stuff. I use a hand miter saw to simply saw off any of the foam that sticks out of past the edge of the window.

 

[lpakiz]

We removed every 12" board and 3" batton of vertical Red Cedar siding to replace all windows and add 1/2" of "DowBoard" insulation. We replaced the boards exactly where they came off of, and I used that canned foam to stop insects and vermin from using the 3/4" voids between boards as a highway. I put a dab at the top, a dab in the middle and a dab at the bottom.
I found that a hot, wide putty knife and a propane torch to heat it would cut the excess foam perfectly. Like a hot knife thru warm butter, you could say.

 

[Buzzard7]

Use spray foam for best insulating value.

 

[dh206]

If you're going to use the window foam (which I highly recommend), and you have 12 windows, it's worth it to spend the extra $20 for the applicator. It will make your job easier and faster and more accurate. There's a "professional" spray foam gun that is reusable. The cans are bigger, so you get more out of a can for about the same price as the consumer can. You can get them at Lowes, HD, or Amazon. Get the spray foam cleaner too and rinse out the gun according to the instructions as SOON AS YOU ARE DONE FOR THE DAY. Don't wait or you'll make the gun a pretty stainless prop that is effectively sealed shut.
And, as somebody else said, the MOST IMPORTANT thing when doing windows is to get the taping/flashing done around the windows right! If you don't do this, you'll have water in the walls, and rot, and then your sheating and insulation and windows and framing all need to be replaced the hard way. Trust me on this, you don't want this. I had to have all my windows replaced and some of the framing around them as a result of this from a professional window installer not properly doing the flashing. It's a very, very important thing.