> For the complete documentation index, see [llms.txt](https://metropolitan-area-planning-counc.gitbook.io/zoning-atlas-appendix/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://metropolitan-area-planning-counc.gitbook.io/zoning-atlas-appendix/interpretation-of-base-zoning-districts.md).

# Interpretation of Zoning Districts

The section of the technical documentation pertains to base zoning districts.

For the base zoning districts in the Zoning Atlas, MAPC defined a basic set of “core fields” covering use allowances and dimensional requirements to populate. The core fields are as follows: 

* Minimum lot size 
* Dwelling units allowed per acre 
* Maximum height 
* Maximum floor-area-ratio (FAR)  
* Whether multifamily housing was a permitted use, and if a special permit was required  

The values in the Zoning Atlas for these fields generally reflect the by-right regulations of a zone as they appeared in the bylaw or ordinance on the date it was accessed by MAPC. The exception to this rule is the four multifamily fields (`MULFAM2`, `MULFAM3_4`, `MULFAM5_19`, and `MULFAM20_`), which capture uses allowed by special permit, in addition to those allowed by-right. 

The pages below describe two our approach to two common interpretation challenges:

{% content-ref url="/pages/-MObDTxIaeAq2\_Z3RZDf" %}
[Not Referenced or Unspecified Core Fields](/zoning-atlas-appendix/interpretation-of-base-zoning-districts/specifies-all-five-priority-fields.md)
{% endcontent-ref %}

{% content-ref url="/pages/-MObDze7v7pMZeJYAULR" %}
[Multiple By-Right Dimensional Regulations](/zoning-atlas-appendix/interpretation-of-base-zoning-districts/specifies-several-but-not-all-priority-fields.md)
{% endcontent-ref %}