Modeling "misaligned" insulation and worse

[Gamaliel Lodge]

Since we have not been able to find a technical definition for the term “misaligned” as it is applied to insulation, we have mapped it to a Grade III installation quality. A Grade III installation has gaps or voids covering 5% of the insulated area. This is modeled in the parallel path calculations view able using the ||Path buttons on the detailed envelope component pages

If the actual installation that you are modeling is worse than Grade III, then you should set the quality to Grade I and manually modify the R-value of the insulation itself. If the insulation is so poorly installed that it is making little to no contact with the interior cavity surface then you should model it as uninsulated. If there are significant portions of contact and no-contact, then follow these steps:

1. Model both insulated and uninsulated scenarios and record the Assembly R-values (reported on the ||Path popups) for each scenario
2. Estimate the area and compute the UA=Area/AssemblyR for each scenario
3. Sum the UA values, divide by the total area, and invert the number (1/x) to determine the properly weighted average Assembly R-value
4. Enter this value in the Assembly R control or increment the Insul R control until the correct Assembly R-value is calculated

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