Windows Doors Wrong SHGC U Value for Rescheck

This was written by Jobe Leonard as a blog post for Rescheck.info and the coveted Reschexpert blog.  Jobe likes creating Rescheck FAQs for others to learn the art of creating their own Reschecks.

Jobe Leonard Rescheck.info

We provide help on Reschecks and all related components on a daily basis.  To help others who have issues getting their windows, doors, and glass to pass in Rescheck Web and Rescheck Desktop we included this interaction with a Rescheck User helping them to find a solution for their issue when they have installed an addition to an existing home using window and door units with to high of U value and SHGC for IECC 2015 and Texas energy codes.  See interaction and picture gallery below.  Thanks for reading the Reschexpert blog.

Hi there,

I’m applying for a building permit in Texas through the City of Houston.

They have asked for the following….

“Please provide an energy report for all windows and doors being replaced. The windows and doors should comply with the 2015 IECC energy code”

Can you help with this?

I’ve attached the drawing I submitted to city.

The U-factors:

(1) Sliding Glass Door – 0.33

(1-3) Windows – 0.46

(4) Window – 0.91

(5) Window – 0.33

The R-value of the insulation in the new wall areas around them:

R-13

Thank you
Anonymous Rescheck Service User

The follow up email from Rescheck.info to Anonymous Rescheck Service User

Anonymous Rescheck Service User

I ran the report but the window information provided exceeds the maximum allowed average of .4 in Texas.  Are you sure those window specs are correct?  A typical window we see sold in Texas typically falls in the .29 to .32 u factor range.

Best regards

Rescheck.info Texas Rescheck Help Provider

The Next Email From Anonymous Rescheck Service User

I could have misinterpreted the labels. I’ve attached them.

I have 3 of these windows:

1 of these windows:

1 large window (16×6) with the Optifloat Clear 3/8 specs:

1 of these sliding glass doors:

This insulation: R 13

Thanks

Anonymous Rescheck Service User

The follow up email from Rescheck.info to Anonymous Rescheck Service User

Anonymous Rescheck Service User

Thank you for the pics and info that was exactly what I needed.  It looks like you read the labels correctly in the original email but those labels definitely give me some more usable data.

Using the new data it actually presents 2 issues.

Your U value is too high, this is your windows insulation capability.  Texas allows .4 average and below.  Your Average is .6

Your SHGC is too high.  Texas allows a .25 and below average.  Your average is .48.  See Rescheck software below.

The only way to lower these scores is with different window units.  The .91 and .77 SHGC window with 104 sq ft is really driving up your averages to the point where it is difficult to get the project back in range.

I am glad to run any additional scenarios for you.  Just let me know what you want to see.

Best regards

Rescheck.info Texas Rescheck Help Provider

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