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by Howard Maple
Houston’s tradition of ADUs
Fans of Shirley MacLaine might remember this Depression-era ADU from Terms of Endearment, the classic 1983 tearjerker that was filmed in Houston.
Although this ADU is no longer standing, the surrounding Houston Heights neighborhood is known for its extensive inventory of accessory dwelling units, which are known locally as “garage apartments.”
Here you can see a typical garage apartment peeking out between two houses in the Montrose area:
In both of these thriving neighborhoods near downtown, ADUs became an important part of the residential landscape during the Great Depression, and in the 1950s, when inner-city neighborhoods saw increased demand for affordable rental housing.
The role of garage apartments today
These same garage apartments that helped Houston homeowners make ends meet during hard times are now helping them deal with soaring inner-city land values and property taxes in the booming local economy. ADU rental income (often over $1,000 per month for an updated unit) can easily cover a homeowner’s annual property-tax bill. (This overheated rental market has led to several blocks in Midtown and Montrose being completely redeveloped into mid-rise luxury apartment projects.)
For individual apartment investors who prefer the traditional charm of Houston’s older neighborhoods, having an ADU on a multi-unit property can be the deciding factor when evaluating whether or not a renovation project is feasible.
“I base many of my property-buying decisions on the existence of one or more accessory dwelling units,”
says Houston apartment developer Mike Ayers, owner of Antiquarian Homes.
“I love old homes, but I’ve turned down purchase proposals on some of the nicest ones simply because they had too much land and not enough rentable units to cover expenses.”
New garage apartments in Houston are often built as an unfinished shell along with a new primary residence, giving buyers the option to create an apartment or guest quarters, a home office, or just an added space for hobbies. Houston contractor Mike Shelton, owner of Harvard Heights Construction, reports strong demand for studio- or loft-style ADU interiors that provide more flexibility than traditional living room/bedroom plans.
How to build one
It is relatively easy to build an ADU in Houston (compared with other urban areas) since this city has always lacked traditional zoning laws. In most older neighborhoods with no deed restrictions, city-wide codes can only dictate basic parameters such as setbacks, insulation standards, and parking requirements. No city-wide ordinance can prohibit specific uses for a building unless health and safety laws are being violated. (Two-story structures must comply with rather stringent utility easement setback rules intended to protect construction crews working near power lines.)
In short, ADUs are allowed “by right” without a conditional use process. There is one important exception: some of the more prosperous inner-city neighborhoods still have deed restrictions that prevent ADUs from being rented.
Here are the documents required to obtain a Houston ADU Building Permit:
There are some design challenges and opportunities.
Parking: The off-street parking ordinance for ADUs can be a design challenge on Houston’s narrow 50’x100′ inner-city lots. Contractor Mike Shelton notes two options for the required third parking space: a 17-foot-wide parallel-parking area, or even a space at the front of the property. Here you can see an approved parking layout for three cars at one of Shelton’s recent garage apartment projects:
Because Houston has a great need for neighborhoods that are denser and less car-dependent, I believe it would make sense to eliminate the ADU parking requirement in the six “Urban Corridors” along the slowly developing light rail system. This development incentive could result in many smaller ADUs being built in neighborhoods within walking distance of a light rail station. (With the growing national interest in simplified lifestyles, housing options for seniors who no longer drive, and even “tiny house” living, demand surely exists for ADUs in walkable, transit-oriented neighborhoods.)
Style: There may or may not be restrictions. Houston neighborhoods that are at least 50 years old and have not experienced significant new development can apply for Historic District status, whereby a petition signed by two-thirds of the property owners usually results in the mandated preservation of every original façade within that district. Garages that were added later, usually in conflicting architectural styles, are considered “non-contributing” structures exempt from preservation restrictions.
Houston’s unique set of rules raises an interesting possibility — could this Texas city, whose metropolitan area is top-ranked for sprawl among metro areas of its size (table 6 in this report) — become a hotbed of housing invention?
“All the discussion on the table is really good and pointed in the right direction,”
“The City of Houston has decided that now’s the time to become a place with walkable neighborhoods and better transit.”
Crossley’s comments reflect the ambitious spirit of reinvention that is always at work in Houston. Indeed, all of the ingredients seem to be in place for a boom in ADU development here:
As Houston prepares for unprecedented population growth in the coming decades, I predict that the versatile ADU concept will continue to help make our inner-city neighborhoods more affordable and sustainable.