Average Fenestration U Factor Exceeds Maximum Rescheck Error

Average Fenestration U Factor Exceeds Maximum Rescheck Error

Why are my window and door U factors failing? Today on the Reschexpert blog we want to discuss some reasons why your average fenestration in Rescheck may be causing an automatic failure for your Rescheck. We broke this blog post into some easy to use sections so let’s get started.

Recently we had a DIY Rescheck creator that could not get their Rescheck to pass because their window U value was triggering an automatic failure within Rescheck Web software. Here are some reasons that you might experience the same Rescheck fail on your own Reschecks.

Your windows are too old: If you go to the landfill or salvage yard and pick out older windows they may not have the insulation abilities of newer windows. You might pay much less for the window units, but over time the costs will even out as you pay more for your energy bills month to month. Also if the U Value or SHGC of these older windows exceeds certain values it can make it impossible to pass a your local IECC energy code and Rescheck.

Your windows were not made for your climate zone: If you designed your home in Maine and are building it in Texas it might have the wrong window specifications for the final destination your home will be built in. Architects or Engineers in the Northeast would spec windows they are familiar with in the plans. When they hit the ground in Texas they may not pass the Rescheck for the local energy code. This is because the difference in climate zones and energy codes from around the country. One big clue that the windows you have on your plans are not made for your area is that they may not be available for purchase locally. If you have to have your windows shipped more than 200 miles to your jobsite it might be a good idea to double check your windows SHGC and U values versus your Rescheck energy report.

Imperial U values versus Metric U Values: The United States uses the Imperial system for numbers and so do Rescheck Desktop and Rescheck Web. This includes the U Value and SHGC. Recently on a United States project near the Canadian borders a project had a ridiculously high U Value on the windows. As I dug deeper into the window package these were very expensive and well made windows. Something was off with the U Values listed on the window stickers and the invoices. After contacting the salesman for the windows we realized the the windows were manufactured in Canada and the U values were listed in the Metric system.

In Utah any U Value over .53 will generate an automatic failure. These windows had an average of 1.54 U value and the building inspector had put a stop work order on the entire project. After solving the Imperial Value to Metric U Value puzzle, I was able to determine that the average U Value of this window package for Rescheck was actually closer to .25.  This is a very well made window that will pass Rescheck in almost any climate zone.

Overall, having a window with too high of a U value can be troublesome for your entire project. Plenty of energy for a home is lost through windows and doors, because they just do not have the insulation capabilities of a fully insulated roof, wall, or subfloor. The heat loss and heat gain of your home will flow through the areas of least resistance and this is almost always your windows and doors. Once you bump up against the automatic failure points of Rescheck Web and Rescheck Desktop in terms of window Rescheck U values it can be hard to reign your project back in. If you understand the limitation of your windows and doors before you order and accept delivery of your window and door package it can save you many heart aches and thousands of dollars.

Thanks for reading the Reschexpert blog and we look forward to helping with your Rescheck. Email PDF plans, jobsite address, and square footage to service@rescheck.info and we will get you taken care of.