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The Mass Wall R-value is editable on the main Walls interface, but not on the ||Path popup.
8″ walls are selectable with the mass wall controls on the main interface. They will be easier to do, because we already have an option for insulated cores. You won’t have to change the Mass Wall R-value control. You can just change the option selected in the second Mass Wall Type control, which defines thickness and core insulation.
I definitely wouldn’t model this as an uninsulated attic. I think you could go a few different ways with this.
- Model it as a conditioned attic, as I described above. Model the roof on the Vault tab and the gable on the Walls tab. This will probably still give you an overestimation, because the attic is still acting as a bit of a buffer space and won’t be maintained at the indoor temperature.
- Model it as an unconditioned attic with the roof insulation moved to the attic floor. You would still model it as two separate sections: 95% insulated and 5% uninsulated. This will probably give you an underestimation of savings, because the total surface insulated surface area will be underrepresented, but you will get the buffering effect of the attic.
- You could follow option 2, but modify the attic area to be equal to the combined roof and gable area. That may swing you back towards a slight overestimation, but is probably the best of the three options. If you have good billing information, then you could try to find a sweet spot between the attic floor area and combined roof/gable area that yields a good calibration.
The Cavity Insulation controls describe insulation added to frame wall cavities. Unless you have a wall framing described, there is no place to put the the cavity insulation. That is why you are getting that message. I can see why this is confusing. I think we could make the interface more clear by disabling the Cavity Insulation controls, when the Framing is None. These Cavity Insulation controls are not the proper place to model insulation poured into concrete block holes.
We do not have a direct method to model this measure, but I can give you a workaround. The options that we have in the Mass Wall control currently limited to items published in the AHSRAE HoF. We don’t have data for a 12″ wall with insulated cores, but we can infer it from the 8″ wall. In the 8″ wall the perlite insulation adds about R-3.1 to the total R-value. (Note that these R-values include an adjustment for benefits of the thermal capacitance of the mass wall). Adding insulate to the 12″ wall may improve the R-value a little more, but due to the dominance of the thermal bridging it wouldn’t be much. I think that the R-3.1 would still be a good conservative estimate. (If you wanted a generous estimate you could assume that the R-value doubles for the 12″ block, as it does for the 8″ block. ) Here are steps to generate an improvement that represents adding the insulation:
- Setup the base wall
- Click the ||Path button to open the parallel path calculator.
- Check that all layers are described correctly.
- Change the Mass Wall R-value to 7.1 (adding 3.1 to the existing 4.0)
- Record the resulting Base Assembly R-value displayed in the calculator.
- Change the Mass Wall R back to 4.0
- Set the Improved Cavity Insulation to None
- Set the Improved Continuous insulation to Other (or a custom entry that you create).
- Set the Improved Continuous depth as desired
- Increase the Improved Continuous Insulation R-Value until the Improve Assembly R-value reaches the number that you recorded in step 5
I think these are usable bills for the following reasons:
- You have one period of known usage that is probably all baseload
- You have other periods of known usage covering a significant portion of a heating season
However, I doesn’t sound like you have a good understanding of how to enter these bills. These dates should be entered in consecutive bill controls in the interface. The controls do not have to represent one month each. You would put the first date (4/13) in the Start Date Bill 1 control. Then put the second date and usage (10/13) in the End Bill 1 control. Thus the first bill will be a long period representing the summer base load usage. Then enter the remaining dates and usages in the next three controls.
You can’t use the usage of the first bill, because you don’t know exactly what period it represents. Unless, the owner knows the delivery date of the preceding delivery within a couple days accuracy. In that case you can put that date in the Start Date Bill 1 control and use the usage from that first receipt.
The Omit boxes are used to make bills that have usages that you suspect to be atypical. If you used the Scrape tool to put in a full 12 months of bills, but you knew that they had a 2 week vacation in August, then you would Omit the August bill. There is no need to check Omit on any row that already has zero usage.
Is the propane used for anything besides heat?
Are all of the deliveries top-offs?
Where there any deliveries between 4/13 and 10/13 ?
If you ever see a red X like that, please send an error report immediate. It is a stability issue with our display of spreadsheet ranges that crops up from time to time. We can’t debug it without an error report, though.
Unless the client has a fixed $/kWh rate or a simple tiered rate without a demand component, you can’t get usage data from bills that have costs only.Unless you have run the Calibration routine at the end of the Wizard, then deleting the utility bills will result in the same state as if you had never entered the bills at all. If you have run the Calibration, then it’s probably best to start from a new file. I could give you an extensive list of actions that you could take to restore most of the defaults, if you think that would be preferable.
Door sweeps and weather stripping belong in the Air Sealing improvement. The Doors and Windows improvements are intended to represent upgrades that improve the conductive or solar properties of those components. Savings due to air sealing can only be calculated with changes to the Infiltration (CFM50) controls and are restricted to the Air Sealing improvement. The cost for these items should be included in the Air Sealing cost.
We are working on improvements to allow multiple options to be more easily specified. There are some methods and workarounds that can be used now, but I am not familiar with them. I’ll get someone else to write them up shortly.
