heat loss question

ddenny

thankyou that was helpful

ddenny

heatloss question

according to the hydronics institute's heatloss calculation guide H-22 the table giving the transmission losses for windows gives different factors for double glass windows, one for without a storm sash and one for with a storm sash. is a storm sash a storm window? the newer windows you can get from the wiindow and siding people; do they have storm sashes usually? thankyou.

Brad White_9

Storm Sash

That term was foreign to me when I started in this business almost 30 years ago, but yes, "storm sash" is the same as a "storm window".

"Sash" as you may imagine is a fixed pane of glass or one of two in a double-hung window arrangement. The older storm windows were really fixed sash and hung on metal hooks, taken down and put up every year, hence the term.

It is NOT an article of clothing

Nowadays we have a variety including Triple-Track storm windows so the original term is somewhat lost to antiquity.

The newer windows? What I have seen they all seem to be double-pane and low-E glass; for this reason I do not see them having a third pane except in certain extreme climates or humid areas like swimming pools. They are available, sure, just less necessary with good prime glass and sealed units.

TONY_22

For new style windows we use the with storm sash values. If you know the r-value of the window you can calculate the u-value. 1/r-value=u-value ie. 1/r-5=.2 u-value