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Discussion Starter · #1 ·
why is it that 2 windows, one wood and the other a high quality vinyl with both the SAME EXACT glass packages,will the vinyl window have better performance numbers?
if the glass package is the exact same,why does the vinyl have a better u-factor and air leakage number? can anyone provide some clarity?
 

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I've never put much though into it, but i know when i redo my house again when we put the addition on next year, i'll be taking the 5yr old vinyl out and installing new wood....i'm tired of the vinyl acting like a big ice cube radiator.:censored:
 

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Just a thought..........

Vinyl windows have an air space. This is a great insulator over solid wood. Not too much different than using the air space in your fiberglass insulation in the walls. Slows the heat transfer.

This sound right to you guys?
 

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Just a thought..........

Vinyl windows have an air space. This is a great insulator over solid wood. Not too much different than using the air space in your fiberglass insulation in the walls. Slows the heat transfer.

This sound right to you guys?

You refering to the airspace inside the rails? as in, wood rails are solid, vinyle rails are not?GMOD
 

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Vinyl rails used to be solid, then they went with insulated, now they are hollow. With the air space, it is said to have better efficiency.

Is this not correct?
 

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We really need to see the data to discuss this intelligently, window brands, styles, conditions etc....GMOD
 

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My common sense thinking to the ole "hollow frame rails" since dead air space is such a great insulator is this:

IF hollow voids and dead air space are such fantastic insulators why is it that:
stud cavities require insualtion to be installed
why do attics require insulation be installed
why are'nt all homes built from cement blocks with all their many dead air spaces
Why do foam filled vinyl window manufacturers claim a MUCH higher overall R factor when comparing frames of theirs to hollow framed units that are a dime a dozen

Plastic itself is a horrible insulator, we know this...put hot coffee in a plastic cup, your hand gets hot immediately. Put cold water in a plastic cup, your hand gets cold immediately. NOW do that same test with a wooden container....i'd bet my life savings (which is'nt much so dont waste your time);) that the wood container will take MUCH longer to transmit the temperature variance from one side to the other. the problem, wood is not a maintenance free product, so they cost more initally and long term, and folks dont want that.

Personally we've installed tens of thousands of plastic windows over the years, some good, some bad, but the one common denominator between the ALL is they transform themselves into big cold radiators during the winter months since plastic has no insulating value that's worth noting and hollow frames/dead air spaces is a crock of chit....look around you and use some common sense and not what you've been told and have over heard over the years and the lights will come on and you'll smack your forehead saying DUH:laughing:
 

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And for the record, the test results.....somebody else hit the nail on the head, as much as they like to tell you there is a standard....they have the universal excuse that is not only used in the window testing industry, but in every industry that gives performance ratings on THEIR product: "test results may vary" and they chaulk it upto the equipment they use vs what somebody else may use. I see this in MANY components in my racing, big name companies all claim cylinder head flow numbers that are very very impressive...but once you get them and take them to a local head shop and they chuck it up on their flow bench, you realized you've been dupped. Head flow #'s can be manipulated with bore sized, fixture placement to give whatever the tester wants it to say.

Just like most things in life- smoke and mirrors to sell a product.
 

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I hear ya IHI.

Just for discussion sake of your coffe cup scenario........

Take a cup that is plastic and your hand gets warm, same with a styrofoam cup, but a cup that has an air space between the liquid and the outside, usually holds the heat in, right?

Same with fiberglass insulation......it really doesn't work if it is packed. The air space is what slows the heat loss. Although the same cannot be said for certain spray foams...............

I don't mean to argue, just questioning for the sake of the conversation here.
 

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I hear ya IHI.

Just for discussion sake of your coffe cup scenario........

Take a cup that is plastic and your hand gets warm, same with a styrofoam cup, but a cup that has an air space between the liquid and the outside, usually holds the heat in, right?

Same with fiberglass insulation......it really doesn't work if it is packed. The air space is what slows the heat loss. Although the same cannot be said for certain spray foams...............

I don't mean to argue, just questioning for the sake of the conversation here.

No, i agree with you since like you said "fiberglass insualtion" and "styrofoam cups" are products with thousands/millions of tiny air pockets, just like extruded foam, millions of tiny air pockets.....so it's safe to say the millions of tiny air pockets are much better than 1 large air pocket. Every cut away with every plastic window i've ever seen has a bunch of large air pockets, and i personsonally think it's a case of these manufacturers getting an inch and taking it a mile. They're using the air space "theory" and exploiting it. The windows i have in my house for instance exceeded energy star rating....yet, they aer bigger units and my couch is always cold over there, the other window the love seat is always cold to the touch during the winter....not too much insualting going on no way no how since the air exchange easily convecs through the plastic...no matter if it has multiple voids are not.

There's lots of good "theories" out there, and also alot of real life apps to squash theories. Dead air space...well, LARGE dead air space such as what comes standard with plastic windows, is no good...i'm yet to stand next to a "warm" plastic window in the winter time, they all transmit the cool through them, but going back to the tiny air spaces, i have stood next to vinyl windows that had filled frames (they fill the "dead air space" you all have seen in vinyl windows with "expanda foam" for lack of better term) and turns that big empty air space into a bunch of tiny/millions of tiny dead air spaces...and now, miraciously they are indeed warmer. Same as a styrofoam cup:) but very few windows come offered with foam filled frames, and the one's i've priced out equivilate to a wood window, so you lose the selling vantage there.

For my concious sake, i forewarn folks prior to commiting to one window type, i tell them the pro's/con's of all the species and how price affects them and why so once we're done, they cant call me back asking why their plastic windows are soo cold, what did i do wrong, what kind of junk did i sell them...

But to stay on topic, manufactuers claim what they claim. Let multiple independant shops test with their multiple brnad equipment and you will NEVER get a repeat answer, everybody's tests will yeild different results.
 

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Just a thought..........

Vinyl windows have an air space. This is a great insulator over solid wood. Not too much different than using the air space in your fiberglass insulation in the walls. Slows the heat transfer.

This sound right to you guys?
Vinyl rails used to be solid, then they went with insulated, now they are hollow. With the air space, it is said to have better efficiency.

Is this not correct?
No it's not. Wood has a R factor of 1 per inch. Pocketed vinyl .2

My common sense thinking to the ole "hollow frame rails" since dead air space is such a great insulator is this:


Why do foam filled vinyl window manufacturers claim a MUCH higher overall R factor when comparing frames of theirs to hollow framed units that are a dime a dozen
Actually tests have proven this to be a myth. The "overall" U factor is not significantly affected with foam frames. It's > .01.
 

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Discussion Starter · #15 ·
then why does a high qualityvinyl window with the same exact glass package from cardinal have better performance numbers than a Marvin with the same cardinal glass package? i am comparing 2 double panes.
 

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then why does a high qualityvinyl window with the same exact glass package from cardinal have better performance numbers than a Marvin with the same cardinal glass package? i am comparing 2 double panes.
Manufacturer testing THEIR product....."RESULTS MAY VARY"

nothing to argue there, they can stamp whatever the heck they want to and redirect questions should they be tested by an independant and drag it out to the point it gets dropped/forgot about. It's not just windows that fall into "rigged" testing.
 

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the vinyl windows i am referring too get tested my AAMA and the NFRC ...how is it rigged?
Like government testing....pocket padding and lobbying funds to keep it alive LOL!! I find it pretty amazing how the Pella Encompass vinyl windows can exceed energy standards to be eligible for the tax credit...yet have no seals other than the felt strip on the sides of the sashes....obivously standards are low to "get in the game"
 

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Discussion Starter · #19 ·
I am talking about high end vinyl windows. pella and andersen vinyl windows are about as LOW END as you can get.
 

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Like government testing....pocket padding and lobbying funds to keep it alive LOL!! I find it pretty amazing how the Pella Encompass vinyl windows can exceed energy standards to be eligible for the tax credit...yet have no seals other than the felt strip on the sides of the sashes....obivously standards are low to "get in the game"
I'm sorry but you are ridiculous. Are you alledging that the AAMA and NFRC are fudging numbers because Pella and Anderson are lining their pockets?! Now I don't believe that government only does things that are in our best interest, but come on! ...and btw, this is hardly the same as edelbrock publishing its own flow numbers for its heads.
 
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