Rescheck SHGC Exceeds Maximum
Today on the Reschexpert blog we ran into an instance where the Mandatory SHGC of windows and glazed doors was exceeded on a project. To help future users of Rescheck Desktop and Rescheck Web meet U Value and SHGC requirements for their online Rescheck form we produced the following Rescheck SHGC FAQ below.
The Rescheck User is the person using Rescheck Web and Rescheck Desktop that is having difficulting passing their Rescheck because the SHGC of their window package is too high.
Rescheck.info is us at the Reschexpert blog trying to help the Rescheck User through the Rescheck process and give them ideas on why their project does not meet IECC compliance, and what remedies they might be able to take. Our responses are also in bold lettering.
Rescheck User: So I have ran into an issue with the SHGC coming in over maximum requirements. I have never used Rescheck software before but I have been trying to work with the program myself. I have kinda hit a brick wall. I have put in all the requirements as asked but even with a ridiculous amount of R-value insulation I am still not in compliance. So I feel like I’m not doing something right. Especially when the SHGC is only off by like .2 of maximum allowed. Please let me know if you can look thru this for me and help me out in any way.
Rescheck.info: SHGC is a mandatory maximum factor that will produce an automatic failure if you are over. That sounds like what you are running into.
Rescheck.info: What is the U-Value and SHGC of your window package?
Rescheck User: I’m not sure about the total average of the window package but I can say that the majority of the windows are listed with a U-factor of .31 and a SHGC as .30. Rescheck shows my UA at 405
Rescheck.info: Also looks like you have a 128 glass door and 48 glass door, what are the U-Value and SHGC?
Rescheck User: The doors did not have tags listing the numbers so for calculation purposes I used the same numbers as the windows just to see where I would be at. I was told by the Lumber store where we bought the doors that with Lowe E glass and being over 15 sq ft that they were exempt? Not sure about that.
Rescheck.info: Are the windows/doors already installed?
Rescheck User: All doors and windows are installed and bricked around
Rescheck.info: If your windows are .3 SHGC then they are .05 out of compliance. .25 SHGC is the Georgia requirement.
It may still be beneficial to get specific information about the exact SHGC of the doors in case they are lower, but you will have a hard time overcoming the .3 SHGC windows in the software.
Since they are installed and bricked around, one solution I have seen in the past is a window film. Similar to the way a car window is tinted a local window tinter may be able to install a residential window film with an SHGC of .25. I am sure that is not the desired solution, but definitely less costly than than removing, returning, and reinstalling a new window and door package.
In the end, your building inspector will have the final say as to what they will except. You might be able to get an exemption, but it is very rare.
As you can see from the example above, solving a SHGC that is too high on a Rescheck is difficult. If you live in a state that has a mandatory maximum SHGC, then you should be aware of this before you estimate, order, or install any window or glazed door onto your project.
If you need help with a Rescheck you can email us PDF plans, jobsite address and square footage to firstname.lastname@example.org and we will get you taken care of.