It is impossible to view the details on that image. Perhaps you can attach an un-resized variant.

The casement is always going to be an air tight operator so there is no surprise there.

The number out of the triple glider is very good if that is the case but with all triple gliders, the number will be a bit artificially depressed as a result of the size of the unit.

Air infiltration numbers are expressed as a air leakage/per square foot.

So...if you have a very large unit, the relatively high amount of air leakage will appear as a fairly small number.

Like I said, I can't read that report image and this somewhat artificially low numbers on sliders is nothing Marvin specific.

What operators are you considering for your home?

As windows on washington said, a casement is NOT a true measure of air leakage since its almost a fixed unit.
The slider is very large and not the size a company would use for structural testing. The best measure for air leakage is a double hung. The standard size for a double hung that is tested is usually 36x63 or somewhere close.
The Infinity double hung as a very high air leakage rate.

This post was edited by mmarse1 on Mon, Sep 2, 13 at 9:59

As windows on washington said, a casement is NOT a true measure of air leakage since its almost a fixed unit.
The slider is very large and not the size a company would use for structural testing. The best measure for air leakage is a double hung. The standard size for a double hung that is tested is usually 36x 63 or somewhere close.
The Infinity double hung as a very high air leakage rate.

...and that is not even a operating casement, it is a FIXED casement which is essentially a picture window. It had BETTER have a great AI rating, lol... The guys above addressed the slider as well. For comparison purposes and because they are the most common by a large margin, double hungs ratings are most commonly cited and is the reason for the discrepancy between what you hear and see... although even with DH's, you have to look at the size of the window to make sure it is an apples to apples comparison. My guess is that if you simply contacted Marvin and asked for the structural reports in regards to air leakage, they just pulled up the best ones that they have and sent them over.

Thank you for all your responses. Very interesting how they attempt to improve their numbers. The triple slider was very large at 115x48".

I did solicit the double-hung numbers and it looks like it tested out at .16, though it was for a 40x86" unit.

WoW - regarding the operators, I hadn't given it any thought. Any recommendations?

Double hungs and Casements will be tighter by design as compared to sliders and larger sliders.

That is a large for a tested unit on the DH as well.

It is somewhat of an accepted industry standard to keep the unit size in the 100 - 105 united inch (width + height).