Utility bill calibration alerts let users know if the heating and cooling usage in the energy model for a job is significantly different from what the utility bills tell us. Calibration alerts are only active if you provide the job with detailed utility bills. The alerts are not turned on when Simple Bills or No Bills are chosen. The alerts do not put a hold on the job, they do not interfere with any functions, and they cannot be seen on the homeowner report.

As explained in our Utility Bill video and in our Utility Bill Calibration Science knowledge base article, including detailed utility bills in your job is the best way to ensure the accuracy of the energy savings calculations. With the calibration alerts, you can now tell how close the energy model was to calibrating to the utility bills. If the data you entered into the Snugg Pro model was not representative of what actually exists in the home, you will likely see a calibration alert. You can tell how far off your data collection was and make adjustments to the energy model to get it to match the actual bills.
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An alert is only activated if the calibration to the heating or cooling usage is off by more than 10% in either direction. If there is an alert, you will see a red badge with a number in it next to the Alerts button at the top right hand corner of the job screen:

Here is an example of what a utility bill calibration alert looks like:

If you have a calibration alert, the very first thing to do is review the utility bills themselves to make sure they look correct. Check that you have entered the correct units (dollars, therms, kWh, etc). Make sure that you have entered meter read dates and not bill dates. Make sure there are no missing digits.
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Then, review the bills to see if there are clear indications of anomalies like electric heat or minimal cooling usage. For instance, if the electric bills show a large increase in the winter months, then the home must be using electric heat of some kind even if the primary heat is natural gas. Or, if the summer months show high usage compared to the shoulder months, the home probably has 100% cooling load, but if the summer months only have a slight kWh increase you probably only have a partial cooling load and that % of cooling load in the HVAC section should be reduced.
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Under each alert, you will see the Show details button. Click on that to see suggestions for how to correct the energy model. These base elements are the most important to look at when trying to calibrate, and usually in this order:
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Base insulation in the attic, vault, floors, and walls are large factors in the calibration of a job. If the calibration alert shows that modeled energy usage is higher than the utility bills, usually it is because the base insulation amount is understated. If the calibration alert shows that modeled energy usage is lower than the utility bills, it is usually because the base insulation values are overstated. Be sure to also consider knee walls, continuous insulation, and quality of installation.

All heating and cooling systems used in the home need to be entered. Space heaters, wood stoves, and windows AC units, for example, should all be entered with the appropriate percent of load. Remember that heating loads need to add up to 100%, but cooling loads can be less than 100%. Accurate AFUE/HSPF/SEER ratings are also important.

Use a range of thermostat setpoints instead of a single number, or if you're already using a range, expand it. You may have the heating temp too high, and/or the cooling temp too low. It may be hard for a homeowner to have a exact number for what temperature they keep the house at 24/7, so a range of temps is more realistic and allows the job to more easily calibrate automatically.

Windows sizes and overhangs can also throw off the calibration. You should check the refine screen details to see if the percentage of windows that you entered on the input screen is a good representation of the home. And remember that the length and width of the home play a factor in this (the % of window area for each wall orientation is calculated based on the length and width of the home). Also, consider the Window Venting option. If your calibration alerts are saying the modeled cooling usage is too high, it’s possible that the homeowners often open their windows when it’s mild outside. Setting the Window Venting field to yes, could easily bring cooling usage into calibration.

Be sure you’re entering the length, width, and number of floors of the home correctly. The length, width, and wall height calculates the total exterior walls. The exterior wall calculation is used when calculating the percent of glass on each wall. When measuring the home, an attached garage, unheated sunrooms, and large covered patios, porches should not be included in the length and width. Read a refresher on how length and width should be calculated.
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Also, be sure that you chose the right box under Conditioned Area for the Area Includes Basement field. Incorrectly checking this box can easily throw the job out of calibration.
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You can use fractions for the number of floors above grade (1.5, 1.8 etc). The Home Energy Score (HES) does not allow for partial floors - but HES will adjust accordingly on their end, the job should not be changed to 2 full floors for example.

Usually, adjustments to the above elements will bring the job into calibration. If you are having a hard time finding the right combination of adjustments, please contact support so that we can review the job.

Example 1: Electric heat is used more than what the model shows

In this case, the home has supplemental electric heat with natural gas for the primary heating fuel. The user estimated that the percent of load for the electric heat was 10% and the gas heating percent of load was 90%. The calibration alerts told us that this probably isn’t the case. If we adjust the electric heat to 20% and the gas heat to 80%, then both alerts go away.

​Example 2: Modeled Cooling load is more than what the bills show

In this case, the job was set to have room AC units that are set to 100% of load. The calibration alert is saying that our model is estimating too much cooling compared to the bills. There aren’t actually room AC units in all rooms of the house, so it’s unlikely that the full cooling load of the building is met by them. Changing the % of load to 75% will bring this job into calibration.

Please see the following video for more examples of calibration: