no window insulation????in a mavin infinity

A place to ask all your replacement window questions
Post Reply
Message
Author
kc
Posts: 7
Joined: Thu Oct 06, 2005 7:04 am

no window insulation????in a mavin infinity

#1 Post by kc » Thu Jan 12, 2006 10:57 am

Hey guys- I have been on this site way more than I ever thought (last post in October!) Anyway- had Shucco out- not NES, but was happy to find another dealer at the home show, but when he cursed out my husband in the driveway- !!!!!
So had a Marvin infinity salesman- asked about the insulation type and where- he said they don't use it since it is fitted to within a 1/4 inch of the dimensions. I know I wrote down a suggestion from one of you pro's that insulation be "around all 4 units of the window" so What am I missing-? He did say there would be beading around the edge (caulking I assume), but it "ain't the same "right? thanks :D

eberry
Posts: 42
Joined: Fri Jan 13, 2006 1:25 am
Location: Central US

#2 Post by eberry » Fri Jan 13, 2006 1:36 am

The gaps need to be filled by something to prevent air penetration. If the gap is small enough, caulk/foam will work. If the gaps are larger than the caulk will easily fill, insulation is a common option. This seems to be the general pattern I see with the installers I've talked to and the DIY tutorials you see on the web.

Guy
Posts: 537
Joined: Thu Oct 07, 2004 12:41 pm
Location: Minnesota

#3 Post by Guy » Fri Jan 13, 2006 10:54 am

You never leave a gap around your frame any time. Like FeneX said, "Air doesn't see the gap and figure it's to small to get through". You must use a good caulking if the gap is to small to insulate. You must also never use fiberglass insulation like others say here. Fiberglass insulation works only in it's uncompressed form. Ounce you compress it, you've lost it's effective uses. Air will pass through it like a light sweater on a cold day.

eberry
Posts: 42
Joined: Fri Jan 13, 2006 1:25 am
Location: Central US

#4 Post by eberry » Fri Jan 13, 2006 12:57 pm

I would like to understand how compressing fiberglass can make it more porous to air. I definitely see how compressing it can decrease the air pockets that are present in the fiberglass and thus decrease the insulative capabilities by removing the well-insulating air. If compressing the fiberglass fibers realigned the fibers in some way to make it more porous, I could see that, but I don't believe (in the fiberglass I've seen) that the fibers are arranged in an organized enough fashion that compressing would introduce new channels for air to pass, instead of just collapsing the existing airspaces.

(I am not a window expert - I'm asking this as an engineer)

windowrep
Posts: 181
Joined: Thu Dec 02, 2004 11:54 am
Location: ne ohio

#5 Post by windowrep » Fri Jan 13, 2006 5:02 pm

i also would like to know. your telling me the more insulation i cram into a crack the worse off i am. if i cram hard enough, i will eventually have a solid matter. what better insulator? same theory as osb sheets. your trying to tell me if i unglue all the particles and have air spaces between them it will be a better insulator? fiberglass insulation should be tucked loosely into any possible crevice. it must be pushed in firmly to be sure that it is contacting all points and if settling occurs it has the ability to move or allow movement. in my opinion. got a buddy at owens corning i will talk to and post more later as to his thoughts. if he says different then i will retract and stand corrected. guy, who is taking over hc for vikings since tice is out?

kc
Posts: 7
Joined: Thu Oct 06, 2005 7:04 am

#6 Post by kc » Fri Jan 13, 2006 5:28 pm

Thank you guys- I will print this and show it to him when and if we get to the negotiation stage-

eberry
Posts: 42
Joined: Fri Jan 13, 2006 1:25 am
Location: Central US

#7 Post by eberry » Fri Jan 13, 2006 6:03 pm


windowmann2000
Posts: 345
Joined: Sun Feb 27, 2005 4:16 pm

Insulation around the frames

#8 Post by windowmann2000 » Sat Jan 14, 2006 7:55 am

All of these post about the insulation around the window seem to have merit but which is best. Some of the people I work for order their windows so tight you can only caulk the edges. While this stops the air flow around the window, what would we see if a thermograph was done-would it show a cold spot all around the window allowing for cold to conduct it's way through and condensation to form on the inside of the home? Would it mean more heat loss? On the other hand if a quarter of an inch is left on the sides to insulate with fiberglass would'nt that solve that potential problem.
My preferred method if the application permits is to foam wrap the window allowing about a quarter of an inch on two sides and 3/8's on top and tuck fiberglass in the corners ( where the foam may not fit right) and caulk both sides-in and out. In my mind now I've secured it from the weather.
What I find is most dealers won't pay for all that and their instructions are just caulk it. Oberon where are you? I"ve been doing this forever but I'm really not sure about that small gap on the sides, how about your imput.

FenEx
Posts: 553
Joined: Thu Oct 07, 2004 11:18 am
Location: Illinois

Reply

#9 Post by FenEx » Sat Jan 14, 2006 11:13 am

Interesting thread. I am interpreting the last two sentences of guy's post to be two separate thoughts. Compressing fiberglass does indeed defeat it's intended purpose and insulating abilty... and, fiberglass by itself is not an effective air barrier.

I read another post pertaining to the use of R-11 verses a higher rated fiberglass batt to be stuffed in around windows. In this application, the rated R-value no longer applies to the product at all. Fiberglass insulation ratings only apply when the product is installed in it's designed and relaxed form and without any voids or variations in it's thickness. For instance, even when it's slightly compressed behind conduit or electrical boxes in a wall, it's R-value drops considerably. Fiberglass itself is not the insulator, the dead air it traps when properly installed is and when it's applied without an adjacent air barrier, it becomes little more than an air filter.

I prefer the use of low-expanding foams. They insulate and air-seal in one step. The foams have a set expansion rate that gives them a more consistant R-value too. The better foams stay flexible to allow movement with expansion and contraction of the surrounding products. At a meeting in DC about two months ago, I was sitting and chatting with an R&D exec. from Dow and he shared that in Canada virtually every window is installed with foam. When airsealing a replacement window that is being installed into an existing jamb, I also strongly recommend caulking around the original brickmould before capping and caulking both edges of the existing interior casing. Clear, paintable caulking works nicely for this as it dries invisible over any existing wall and trim finished surfaces.

eberry
Posts: 42
Joined: Fri Jan 13, 2006 1:25 am
Location: Central US

#10 Post by eberry » Sat Jan 14, 2006 1:40 pm

Sorry, Guy, if you meant your last two sentences as separate thoughts (no cause and effect), I think we probably agree on this, and I apologize for misinterpreting you.

windowmann2000, I would guess it is impossible to restrict airflow enough using fiberglass + caulk combinations. And as we mentioned, once you disturb the air pockets in the fiberglass insulation, the insulative ability (R-value) will go down by some unpredictable but potentially large amount. So though it is commonly used and probably acceptable to many people, I don't see how fiberglass is a great option, given that there are other well-tested and likely better performing alternatives.

From an engineering perspective (I don't have hard data), I agree that the foams make the most sense to me because they seal, insulate, and expand/contract fairly well, which the other options do not do. I would guess that the closed cell foam wraps are the next best option, maybe with more foam in any remaining areas the foam wrap does not cover. That said, I'm sure it is hard to change years of training, and I'm guessing we'll continue to see fiberglass around windows for decades.

FenEx, I was the one that said I would prefer higher R-Value fiberglass to lower R-Value (if I was using fiberglass with my windows, as most around here seem to). I wouldn't be surprised if the R-Value of fiberglass placed in window gaps will change dramatically enough, due to deformation of the structure, that higher R-Values have a greatly diminishing return and that even larger R-Value differences are not adding enough value for the extra money (given the other areas where most homes are busy being energy inefficient).

FenEx, can you recommend any specific foams you've seen tested/used used that have these good properties we're talking about and are also cost-effective and available?

Thanks to everyone for their contributions to this message board - I enjoy discussing and continuing to learn about these things.

FenEx
Posts: 553
Joined: Thu Oct 07, 2004 11:18 am
Location: Illinois

Reply

#11 Post by FenEx » Sat Jan 14, 2006 4:53 pm

Eberry

The R-values given to fiberglass batts/blankets only apply when installed as designed and based upon their density in relaxed form. These R-values are due to their overall thickness and ability to trap air (the insulator), not the fiberglass itself. In 2x4 construction, you can obtain batts that have R-11 or R-13 for the 3.5" cavity but this is because shorter fibers are used for the R-13 and the greater density creates more/smaller air spaces. R-19 and R-30 batts are simply thicker for larger available framing areas allowing them to hold more air, not different products per inch. Compress any of the above and you drastically reduce it's effectiveness.

Closed cell foams cure in their applied surroungs unlike foam tapes which are compressed upon install, changing their engineered and manufactured pre-set attributes. There are several good commerically available products but they are not easily accessible by homeowners. Homeowners and most contractors will do just fine with the DOW Great Stuff Window and Door (blue can). Here's a link I found with a good info page. It's for the Pro-Series which gives a greater yield and has a gun applicator but the chain store cans will work too. Professional guns on the market have skewed tips available to get into smaller crevices without the mess.

http://www.wind-lock.com/sys/docs/pdf_p ... sal_83.pdf

eberry
Posts: 42
Joined: Fri Jan 13, 2006 1:25 am
Location: Central US

Re: Reply

#12 Post by eberry » Sat Jan 14, 2006 5:53 pm

FenEx wrote:R-19 and R-30 batts are simply thicker for larger available framing areas allowing them to hold more air, not different products per inch.
Thanks for the more detailed info. I'm leaning even more towards foam after learning a little more about the design of the higher-R fiberglass isulators and their limitations in tight spaces. I guess it would be best to remove the closed cell foam wrap from the windows, even if it comes with it, if appropriate can/tube foams are used.
FenEx wrote:contractors will do just fine with the DOW Great Stuff Window and Door (blue can).
This is exactly what I was loking for - Thanks again!

Guy
Posts: 537
Joined: Thu Oct 07, 2004 12:41 pm
Location: Minnesota

#13 Post by Guy » Sun Jan 15, 2006 3:13 pm

Sorry I was out of town so I couldn't post back. Thanks for interpretation of my statement Fen. They were two separate issues that I see look combined. My apologies to those who misunderstood.

FeneX has answered most of these issues at hand. I will just add that you can pack insulation until it bows the frame or you can't fit any more in there. You will still not stop air infiltration to pass through it. Windowrep your comparison of fiberglass insulation to OSB is not fair. Since OSB is a combination of resin glue and wood shavings that create a solid substance. A better comparison would be a thick wool sweater pulled apart vs bat insulation.

Just for the record I did this study on my own home. When I replaced windows I used fiberglass insulation in a couple and Great Stuff low expansion foam in some of the others. I then capped and sealed up the exterior the same on all the windows. I tested with smoke to see if the air was coming past the fiberglass or the foam. The foamed windows showed no air movement in any place. The fiberglass windows were showing leaks in about four spots on each window, all in different places. Needless to say the fiberglass can't expand to fill those spots that are inset or unseen by the installer. The foam on the other hand will expand enough to fill any unforeseen areas. So seeing is believing for me!!

We use either Great Stuff (Blue Can) or Dow's low expansion foam. Either one will work well.

As for the Vikings, they hired offensive coordinator Brad Chlldress from the Eagles as Head Coach. He hired Darrell Bevell from Green Bay as Offensive Coordinator, Defensive Coordinator Mike Tomlin from Tampa, Darrell Wyatt as receivers coach from Oklahoma Sooners, former Detroit Lions assistant Pat Morris as offensive line coach, Wisconsin Badgers assistant Jim Hueber as assistant line coach, former NFL tight end Jimmie Johnson as tight ends coach and Wisconsin Badgers assistant Brian Murphy as assistant special teams coach. Thats all I know about so far!!

Post Reply