Some of the luxury homes I am rating have features that can use additional energy, but may or may not be outside of the thermal envelope.
I would like to have a document to give the designer that clearly states how I would account for these in a rating. I also want to give an accurate and honest rating and discourage energy-hogging features.
In some cases, there is a question of whether or not an area is part of the thermal envelope. For the sake of discussion, let me give some examples of what I have run into, or could run into in the future:
- an outdoor swimming pool that is heated by the boiler that provides the home's indoor heat and DHW heat.
- an attached garage with its own zone for in-floor heat.
- an attached multi-season porch with its own zone for in-floor heat
- a basement storage area that is under an outdoor porch floor. No heat source and separated from basement by insulated wall and door.
- driveway snow melt system (I haven't run into that one yet, but it could happen)
Frankly, I'm going to be the bad guy here and I don't want it to sound like its just my opinion.
You have 5 items.
# 4 is obviously outside the Thermal Enclosure
# 5 should have its own source of heat and would be a non-rated item; if it shares a heat source then it is up to your provider
The rest need a decision by your provider. Perhaps even RESNET.
I don't have any good advice, but my opinion is that the owners of homes with obvious energy waste "just because I want it" need to include the usage in the rating, and compensate otherwise if they want a reasonable rating. Energy use is energy use no matter where it is used.
A couple that I've seen (on the same house): N. gas space heater on a screened porch and a 250K BTU patio heater.
And the most ridiculous one that I've read about (so far): air conditioned open patio, along with two patio heaters at the "Vision House".
So, there are at least two bad guys so far...