Window ratings numbers, air infiltration, U-factor

Ask replacement window questions & get answers!
Post Reply
Message
Author
Anlina
Posts: 29
Joined: Thu Jan 17, 2019 3:40 am

Window ratings numbers, air infiltration, U-factor

#1 Post by Anlina »

Are air leakage and air infiltration the same thing?
The air infiltration for Milgard Tuscany vinyl casements ranges from 0.05 to 0.08.
Are those numbers good enough if I want sound reduction? The STCs are okay, but
I don't want a high air infiltration to compromise the sound reduction capability.

With 7/32 laminated over 1/4, the ratings are: U-factor .32, SHGC: .34

And with 3/16" over 1/4" Clear, the ratings are: U-Factor: .27, SHGC: .19

From what I've read, the U-factor shouldn't be higher than .25.
I would think the thicker glass would have better numbers!

Thanks.

User avatar
HomeSealed
Posts: 2996
Joined: Mon Feb 15, 2010 3:46 pm
Location: Milwaukee, Madison, SE Wisconsin

Re: Window ratings numbers, air infiltration, U-factor

#2 Post by HomeSealed »

In my opinion, if the window is built reasonably well and properly installed, the air "tightness" of that window should not be any issue in mitigating sound. In the areas that its sold, Milgard is well regarded to my knowledge.

Yes, air infiltration and air leakage for the purpose of ratings are interchangeable.

On the U factor and SHGC, while a lower U factor is always better, the climate will affect the desired SHGC, and there can be some tradeoff in U value accordingly. Really depends on where you live and how much you heat your house vs cool it. To take it even further, it can be dialed in by the facing direction of each wall, landscaping and design features of the home (anything that enhances passive solar gain in colder climates, etc), although in most cases home design and the living habits of the occupants mitigate the smallish gains that could be seen... If you are in a hot region burning up your AC unit, you'll want the SHGC a bit lower.

Anlina
Posts: 29
Joined: Thu Jan 17, 2019 3:40 am

Re: Window ratings numbers, air infiltration, U-factor

#3 Post by Anlina »

Thanks so much, Home Sealed. That's very helpful.
I'm in Los Angeles, BTW. :)

Post Reply