Energy standard inconsistencies

[kamilakrych]

In the documentation, it says that we use IECC 2006 for "standard" energy standard and IECC 2012 is used for "efficient" energy standard. However, Sahin and I found out that this is not the case. Below, you can see the U-values of external wall insulation (in blue). We see that BuildME values are not the same than the ones we found today when looking at the IECC archetypes. These were taken for the SFH, but I checked that the MFH has exactly the same values.

For this reason, a few questions to you @nheeren:

1. Should I fix the U-values of the "standard" and "non-standard" archetypes?
2. On another note: the U-value currently is being modified through insulation conductivity. Wouldn't it be better to change it using thickness? Because essentially, when we sum up the material demand using BuildME, it would seem like the three archetypes have the same amount of insulation.
3. The documention I mentioned at the beginning of this file could be improved:
   • The function apply_energy_standard() doesn't exist - probably you refer to one that's called apply_obj_name_change() (?)
   • Energy standards include also verying infiltration values. How were these obtained? I remember we discussed it at some point, but I don't remember this anymore, and anyway, this should be somehow documented (at least mention it should also be changed).

[kamilakrych]

Fixed by applying the same energy standard assumptions across all archetypes. The description can be found in docs/archetypes/US_archetypes.md