Bug Fix: Too many bedrooms for small units

[afontani]

Pull Request Description

Companion PR: resstock-estimation (#104)

This pull request updates the number of bedrooms for small units.

Problem

For small buildings "0-499", there is a possibility for the unit to have up to 5 bedrooms. The large number of bedrooms do not satisfy the following constraint in the geometry measures:

(CFA-120)/70 >= BEDS

CFA: Conditioned Floor Area
BEDS: Number of Bedrooms

As a result, HPXML is throwing an error.

Solution

After taking a look at the ffa values for the different model types in options_lookup.tsv, the smallest dwelling units have some bedroom constraints:

Bedroom limits based on current ffa in options_lookup.tsv

• Single Family Detached, 0-499 ft2
  • total_ffa=328 only permits 1 and 2 bedrooms
• Single-Family Attached, 0-499 ft2
  • total_ffa=317 only permits 1 and 2 bedrooms
• Multi-Family, 0-499 ft2
  • total_ffa=333 only permits 1, 2, and 3 bedrooms

Implemented Assumption: Dwelling units that are 0-499 ft2 will have a maximum of 2 bedrooms.

According to the constraint and the ffa values in options_lookup.tsv, multi-family units can have 3 bedrooms. However, these dwelling units are close to the constraint above. As a result, a more uniform assumption is applied to the building stock.

Checklist

Not all may apply:

• Unit tests have been added or updated
• All rake tasks have been run, and pass
• Documentation has been modified appropriately
• Any new options are added to project_testing
• project_testing runs without any failures
• No unexpected regression test changes
• All tests are passing
• The changelog has been updated appropriately
• This branch is up-to-date with develop

For more information on how to perform these checklist items, see the documentation's Advanced Tutorial.