Accessory Dwelling Units (ADUs)

From AURAWiki
(Redirected from ADUs)
Jump to: navigation, search


ADUs, also known as garage apartments, granny flats, or backyard cottages make housing more affordable, improve tax base, provide income opportunities for homeowners, increase neighborhood diversity, and reduce sprawl - at no cost to taxpayers. ADUs should be allowed on every neighborhood lot in Austin.

The Problem

As written, the CodeNEXT draft does not easily allow the construction of the simplest form of infill. In 2015, Austin City Council allowed more ADUs to be built, and disappointingly, CodeNEXT has further restricted those amendments. Constraints such as setbacks, height limits, footprint requirements, and placement make it extremely difficult, if not impossible, to build ADUs in both transect zones and new nontransect zones.

Recommendations

Comment Sections/Pages
The code should not mandate that the ADU have a smaller footprint, a narrower width, and a depth not greater than the primary building or to be smaller than the adjacent building. These provisions would frequently require older homes that are small and near the street to be torn down so that the new ADU can fit within the rules. Instead, we should eliminate this requirement so that the entire lot doesn’t have to be demolished and reconstructed—just the ADU behind the old, small house. 23-4D-2060 (section E) pg 11

(pdf 95)

The code should allow ADUs in front of or to the side of the primary unit. Again, depending on the placement of the older home on the lot, this could force the unit to be torn down to build an ADU. There’s no reason to mandate specific placement—especially when considering that some lots are not deep, but are wide. Allowing the ADU in the front could even allow some small old houses to be preserved: designate the existing small house as the ADU and build a larger house in the back. 4D-2 pg. 11

(p. 95)

The side, rear, and front setbacks leave very little room for an ADU on most lots. In particular, the 20’ rear setback is the same for the primary structure and the ADU where alleys do not exist.

The rear setback should be five or ten foot setbacks for the ADU. The code should encourage ADUs by allowing for smaller setbacks when an ADU is built.

  • T3NE.WL 23-4D-2080 Section E page 21 pdf 105
  • T3NE 23-4D-2090 Section E page 27 pdf 111
  • T3N.DS 23-4D-2090 Section E page 33 pdf 117
  • T3N.IS 23-4D-2090 Section E page 41 pdf 125
Requiring ADU's to fit in a 28x24 footprint is overly restrictive. Considering that front houses have irregular shapes and other site constraints (trees, floodplain, drainage and other easements). If an ADU is under 1100 sq ft the ADU should not have to abide by the 28x24 footprint. This would also not allow 1 story 1100 sq ft ADU's.
  • T3NE.WL 23-4D-2080 Section D page 20 pdf 104
  • T3NE 23-4D-2090 Section D page 26 pdf 110
  • T3N.DS 23-4D-2090 Section D page 32 pdf 116
  • T3N.IS 23-4D-2090 Section D page 40 pdf 124


Requiring parking behind the front facade of the building should be taken out. It will make it difficult to build ADU's and keep this existing house since currently many houses have parking pads in front of the front facade of the building. Most central Austin lots don't have room for rear parking for the front house and a ADU on the back part of the lot. Additionally this will increase impervious cover and hurt affordability by requiring longer driveways.

Requiring lots with an alley to only have parking accessed from the Alley should be taken out. This should remain as an option and not a requirement. This will increase impervious cover and hurt affordability by in many cases requiring longer driveways. In addition this will not be possible in many cases because of trees, floodplain and other site constraints. It will also make ADU's more difficult because the back of the lot is where most ADU's are placed. Additionally by increasing impervious cover it will be difficult to do much on these lots besides have a primary house and a long parking driveway from the back of the lot to the front house.


  • T3NE.WL 23-4D-2080 Section I page 22 pdf 106
  • T3NE 23-4D-2090 Section I page 28 pdf 112
  • T3N.DS 23-4D-2090 Section I page 34 pdf 118
  • T3N.IS 23-4D-2090 Section I page 42 pdf 126


The restrictive covenant agreement requirement for the non-transect zone should be completely removed. It’s unenforceable and abhorrent, but will also significantly restrict the production of new units and creates a code enforcement nightmare for the owner and lender. For example, from the perspective of the lender, what happens if the property is foreclosed? How can the owner reside in one of the units? It may be safer for the lender to pass on the loan rather than possibly violate the covenant. What’s more, an occupancy requirement was specifically rejected by Austin City Council in the 2015 ADU reform ordinance. 4E-6 pg. 4 (p. 424)
Remove the restriction that ADUs aren’t allowed for large form houses. If the ADU can fit, it should be allowed. Why create that restriction and block more housing? 4D 2060, pg 10 (pdf 95)
The tree ordinance of the code allows for reasonable use. Reasonable use needs to be defined. Here is how it should be defined. A reasonable use allows to meet all current other codes and for A) A main house with 1000 sq ft ground floor and a ADU with 600 sq ft of ground floor OR if the front house is to be preserved (and its over 10 years old) reasonable use should always allow for the current house to stay in place and a ADU with 600 sq ft of ground floor to be built. 23-3C-2020 D-2 pg. 2 pdf 32 (Under General Planning Standards)
There are exceptions to the 100 year floodplain that apply to duplexes and houses but not to ADU's because at the time they were written people didn't think of ADU's. This section of the code is left out what we see in codenext but we can comment at the top of the floodplain section. Here are the two main ones.

1) Houses and Duplexes are allowed to be built on previously subdivided lots in the 100 year floodplain if the finished floor elevation is 1 foot above the floodplain. ADU's should be included in this exception. 2) Houses and duplexes that are out of the floodplain are not required to have a point on the exterior of the property abutting public land that is one foot above the floodplain. ADU's should be included in this exception. 3) A general statement that an exception provided for duplexes and houses should also apply to ADU's.

We can make these comments at the top of this section

23-3D-4 D-2 pg. 1 pdf 67 (Under General Planning Standards)
Page 99 defines the ADU type. This a good place to describe how all the issues combined make ADUs impossible. In transect zones behind the facade of the main building codenext requires ALL the parking for the 2 units. The ADU which now can't be wider than 28 feet. A 10 foot setback between the units. A 20 foot rear setback. Zero impact include parking pads on the 1/2 CRZ zone of protected trees. A combined 15 foot side setback. A open space that is 8x10. The code seems to assume lots are 200 feet deep while most lots are only 120 or 130 feet deep. LMDR is not much better with a restriction that nothing can be a 2 story beyond 80 feet. 23-4D-2060.A (last form listed) pg. 15 pdf 99
ADUs shouldn’t have its own height restrictions— just rely on the primary building limits. Again, sometimes the ADU may be the “larger” unit when an old small home is preserved.