Cities | Houston

Houston Multiplex Rules 2026: No Zoning, Chapter 42 Lot Sizes

Houston has no zoning code, so no city map assigns your lot to a "single-family" or "multifamily" zone. Four other sets of rules decide what you can build: Chapter 42 of the City code (lots, plats and building lines), Chapter 26 (parking), Chapter 19 (flood elevation), and the deed restrictions recorded on your subdivision. This page gives the numbers in each, with the section that sets them.

State Law in Houston, in Brief

Houston had 2,304,580 people in the 2020 Census, and Harris County had 4,731,145, so Houston passes the size test in the 2025 laws, by VanPlex count from 2020 Census figures. Those laws are written for cities with zoning. SB 15 reaches tracts "located in an area zoned for single-family homes," and SB 840 reaches land in a "zoning classification" that allows commercial use. Houston has neither zones nor zoning classifications, and its Chapter 42 already allows lots inside the city to average 1,400 square feet, below the 3,000 square feet SB 15 sets. Ask the City's planning staff how they apply the two laws to your land. HB 24 governs protests against zoning changes, which Houston does not make. Texas has no statewide accessory dwelling unit (ADU) law.

Two Homes on a Single-Family Lot

Chapter 42 defines the uses that matter. Its Sec. 42-1 says "single-family residential" means a lot with one building "containing not more than two separate" units, and adds: "A lot upon which is located a free-standing building containing one dwelling unit and a detached second dwelling unit of not more than 1500 square feet shall also be considered single-family residential."

So under the City code, a single-family lot can hold a duplex, or a house plus a detached second unit such as a garage apartment of up to 1,500 square feet. The City's Livable Places FAQ puts it this way: "the City's development code allows duplexes on a single-family lot. However, the City does not allow construction of a duplex if deed restrictions prohibit more than one dwelling unit on a lot."

The same FAQ covers narrow lots. Lots under 33 feet wide that take access only from the street must use a shared driveway with one entrance no wider than 16 feet.

Lot Size Rules in Chapter 42

Houston's extraterritorial jurisdiction (ETJ) is the unincorporated land outside the city limits where the City applies its plat rules. A plat is the recorded map that divides land into lots. Lot size depends on which side of the city limit you are on, and inside the city it can go below 3,500 square feet when the plat meets the performance standards or provides shared open space.

Source: Houston Code of Ordinances, Chapter 42, Article III, Division 4. Sec. 42-184 as amended by Ord. No. 2023-801, effective November 27, 2023.

Some terms need a plain reading. A gross acre counts the whole tract, streets included. A permeable area is ground that water can soak into, such as grass or gravel. A shared driveway serves several lots, and a permanent access easement is a recorded right for lots to cross another piece of land to reach the street. A flag staff is the narrow strip that connects a rear lot to the street.

The 1,400 figure is an average. A plat may include a lot under 1,400 square feet only inside the city, only when every lot takes access from a shared driveway or permanent access easement, and only when the average lot is at least 1,400 square feet. For that average, Sec. 42-181(c) counts any lot over 3,500 square feet as 3,500. The compensating open space route works another way: a plat with an average lot of 1,400 to 1,999 square feet must set aside 600 square feet of shared open space for each lot inside the city, or 720 in the ETJ.

Multi-Unit Residential: Three to Eight Homes

Sec. 42-1 defines "multi-unit residential (MUR)" as one or more buildings on a tract inside the city with a total of three to eight units, "which may include multiple duplexes, triplexes, quadraplexes, and apartments and condominiums." It defines "multi-family residential" separately as three or more units on a parcel.

Sec. 42-237, added by Ordinance No. 2023-801 and in force since November 27, 2023, sets the standards for an MUR site:

• a site of at least 3,500 square feet, with at least 50 feet of frontage on a 50-foot street, and no more than 150 feet deep;
• at least 3 and no more than 8 units, and no more than 4 units on a site along a local street;
• a 5-foot building line on public streets other than major thoroughfares, and 15 feet on a major thoroughfare with a right-of-way of 80 feet or less;
• building height of no more than 30 feet, measured from average grade to the highest roof;
• parking on site at the side or rear, one driveway of no more than 16 feet when there is no alley, and one guest space for every 6 units.

A building line is the required distance between a building and the street. For a fourplex on a local street, Sec. 42-237 is the City code section that applies, and any deed restrictions recorded on the site still apply.

Courtyard Developments: 1,800 sq ft per Unit

Sec. 42-194 sets rules for courtyard-style development: small lots grouped around a shared open court. No lot may be more than 3,500 square feet, and the code says "no unit on a site can exceed 1800 square feet in floor area." The site needs at least 50 feet of frontage, no part may sit more than 150 feet from a street, and the main courtyard must have at least 480 square feet plus 150 square feet of courtyard for each lot.

One City document disagrees with the code. The December 2023 Livable Places user guide gives a "maximum unit size of 1,500 square foot." The City's FAQ says the Planning Commission raised the cap "from 1,500 SF to 1,800 SF," and the adopted code says 1,800. The code controls, so 1,800 square feet is the cap.

Parking Under Chapter 26

Houston kept parking minimums and tied them to unit size. The table comes from the off-street parking table in Sec. 26-492, amended by Ordinance No. 2023-802.

Unit size changes the count. A garage apartment of 1,000 square feet or less adds no parking space when the main house already meets its own parking. Four MUR units of 1,000 square feet or less need four spaces plus the guest space rule in Sec. 42-237.

Special Minimum Lot Size Areas

Neighborhoods without a minimum lot size in their deed restrictions can ask City Council to set one. Under Sec. 42-197, a special minimum lot size block is one blockface, or two blockfaces facing each other, where at least 60 percent of the lots are single-family. A special minimum lot size area has at least five blockfaces of five or more lots each, up to 500 lots in one plat or 400 across several plats, and at least 80 percent single-family use. Under Sec. 42-207, a designation made on an application completed after May 24, 2013 lasts 40 years unless Council ends it sooner.

A blockface is the row of lots on one side of a street between two cross streets. Ask the City whether your block or area has a special minimum lot size designation before you plan a replat into smaller lots.

Deed Restrictions and How They Are Enforced

The City's September 27, 2023 release says: "The new standards will not override active deed restrictions." The FAQ adds: "The City has no authority to override or supersede active, private deed restrictions."

The City also enforces them. The Legal Department's deed restriction page says the City may enforce, by suit for injunction, certain restrictions that affect subdivisions in the city, under Local Government Code chapter 212 and Sections 10-551 to 10-555 of the City code. Its hotline is 832.393.6333. Under Local Government Code 212.153, the city may not sue if a property owners association with power to enforce the restriction files suit first.

Owners can also extend or change restrictions by petition. Property Code chapter 204 applies in a county of 3.3 million people or more; Harris County had 4,731,145 in the 2020 Census. A petition approved by owners of at least 75 percent of the real property in the subdivision, or a smaller share if the original instrument allows it, can extend or modify the restrictions. Courts read restrictions broadly under Property Code 202.003.

Floodplain Rules in Chapter 19

Houston's flood rules came from Ordinance No. 2018-258, adopted April 4, 2018 and in force since September 1, 2018. Sec. 19-33 requires new residential construction, additions and substantial improvements in the 1 percent flood zones (A, AE, AH and A99), and new residential construction in the X Shaded (0.2 percent) zone, to have "the lowest floor and all utilities" at or above the minimum flood protection elevation. Sec. 19-2 defines that elevation as "the 0.2 percent flood elevation, plus 2 feet."

A 1 percent flood zone is land with a 1 in 100 chance of flooding in any year. The 0.2 percent flood is the 500-year flood. In an AO zone, new homes must raise the lowest floor at least two feet above the depth number on the Federal Emergency Management Agency (FEMA) map, or three feet above the highest nearby ground if no depth is shown. The insurance and flood page covers flood insurance.

What the Numbers Show

Houston had 2,397,315 people on July 1, 2025, by the Census Bureau's Vintage 2025 estimate. In 2025 it issued permits for more two-unit buildings than any other Texas city in this guide.

Source: Census Bureau Building Permits Survey, South Region places, 2025 annual, estimates with imputation.

The 1,054 two-unit buildings held 2,108 homes. Houston permitted 2 buildings of three or four units in the same year. The Census counts a building by the number of homes it holds, and cities classify attached townhouses in their own ways, so read the rows as permit counts only.

Permits and Fees

Plats follow Chapter 42, and the City's Chapter 42 amendments page lists the recent changes. For the building permit, Local Government Code 214.904 gives a Texas city 45 days to grant or deny an application, give written reasons it cannot yet decide, or agree on a deadline. If it misses the deadline it may not collect the permit fees and must refund any it took. VanPlex did not verify Houston's adopted fee schedule, so this page gives no fee amounts. Ask the City for the current schedule.

Where to Go Next

Related on VanPlex: Houston in the global multiplex zoning comparison, the how Texas zoning works page and the Texas multiplex guide overview.

Frequently Asked Questions

Official sources (checked October 2026)