Multi-generational house - regulations and the addition, guest house, breezeway design

Olathe ADU presentation

When we first decided on the modern farmhouse (and the multi-generational design), we originally hoped to have two homes.  In a prior POST, I talked about how zoning regulations will often dictate whether a guest house plan will work.  This post focuses on the regulations we encountered when planing and designing the farmhouse with an addition or breezeway concept.

The pasture we picked was zoned single family, therefore the opportunity to divide it into two parcels was out of the question.  However, I thought to myself, "No biggie, we will just put two houses on the property--problem solved!"  Like many of the twists and turns of this adventure, my initial ideas turned out to be far more complicated than originally thought.

It turns out, many counties and cities have regulations that dictate whether you can build a guest house, and if allowed, the size and location of the guest house. Our little pasture is located in unincorporated Johnson County, Kansas. The county created refers to guest houses or in-law suite additions as accessory dwelling units (or ADUs).  

Question 1:  Why do I care what the county thinks?  

Well, fair question, I often wondered this very thing. However, every builder will likely need to obtain a building permit from the city and/or county in which you are building.  It is so much better to know and adhere to the regulations upfront rather than risk your permit not being approved and having to start the whole architecture and design process over again (and all the associated costs).

Question 2:  Okay, what the heck are these regulations then? 

Here is a link to the regulations - ADU regulations

Flip down to page 18-11 and you will see the particular regulations on a guest house or in-law suite addition.  The parts I cared about were the performance standards, or in normal-people speak, the requirements your structure must meet to be approved.   Here are some of the key sections:

First, you need to have a lot that is at least two acres and you can only have one of these ADUs.

Then the regulations are broken up between attached and detached ADUs.  Again, normal-people speak translates these into either a guest house (detached ADU) or an in-law suite (attached ADU).

The distinction between the attached/detached ADU matters a lot...as they often say, size matters!

For attached ADUs, or in-law suites, they can only be up to 50% of the main house square footage (ex:  if your main house is 3,000 sq ft, then attached in-law suite can only be up to 1,500 sq ft).  However, if you build a detached ADU, like a guest house, it can only be up to 900 sq ft.  Clarification:  finished square footage does not include unfinished basements or garages.

Well, this part of the regulations primarily drove our decision -- attached it is!  My parents were not at all okay with only 900 sq ft.  

Question 3:  What makes something "attached"?  So, not that I try to bend the rules or anything, but I wanted to know if we could perhaps have an attached guest house that was connected to the main house by a breezeway.  I actually just called the county up and talked with the individual who actually drafted the regulations and was the person who would approve/disprove the permit.  She was extremely helpful!  In fact, she offered to review any preliminary sketches we had from the architect to provide her insights.  She shared that a breezeway connection would likely be considered a detached ADU unless it had a conditioned (meaning enclosed, heated/cooled, finished) conveyance between the main house and the ADU.  You will see how these choices impacted the floor plan in our next post!

Question 4:  Why all the regulations?  I know, I know, I had the same feelings.  However, it did sort-of make sense to me when I called the county.  The county mentioned that it was difficult to write regulations that supported multi-generational housing but prevented people from building a duplex on a single family zoned lot.  

Let me know if you have any questions!  Reminder that regulations and laws change all the time, so make sure to check with the municipality/county in which your pasture is located to confirm.