What happens if you build without a plat in Houston?

Three separate consequences. Inside the city, violating Chapter 42 is a criminal offense and each day it continues is a separate one. In the extraterritorial jurisdiction it is not an offense at all and no fine applies. But everywhere the city may sue to enjoin the violation or recover the cost of fixing it — and the building official cannot issue permits, nor the utility official connect water or wastewater, to a tract that was not properly platted.
Applies toLand in Houston and its extraterritorial jurisdiction subject to Chapter 42 — but the consequences differ sharply between the two, and Sec. 42-5(b) is the reason. This page covers the enforcement provisions of Article I. It does NOT cover when a plat is required in the first place (that has its own page), the doubled application fees for unauthorised work under Sec. 42-54(b), enforcement of private deed restrictions, which are not city ordinances and are enforced by whoever holds them, or the penalty schedule in Sec. 1-6 of the Code, which is outside this chapter.

Three mechanisms, operating independently

Chapter 42 does not rely on a single enforcement route, and the three it provides are expressly cumulative. Sec. 42-5(a) states that prosecution or conviction "shall never be a bar to any other remedy or relief," and Sec. 42-5(c) confirms the city may pursue the judicial remedies in addition to criminal prosecution.

They are not equally important in practice. The criminal provision is limited by geography, the judicial one requires the city to go to court, and the third — withholding permits and utility service — requires nothing of the city at all beyond declining to act.

MechanismInside the cityIn the ETJ
Criminal offense (42-5)Punishable under Sec. 1-6; each day is a separate offenseNot an offense; no fine applies
Injunction (42-6(1))Available, including for a threatened violationAvailable — Sec. 42-5(c) reaches the ETJ
Damages to fund compliance work (42-6(2))AvailableAvailable
Building and utility-installation permits withheld (42-7(a))Yes, for unplatted lots and unapproved developmentsNot stated — subsection (a) is limited to tracts "within the city"
City water and wastewater service withheld (42-7(b))Yes, absent satisfactory evidence of compliance at the time of applicationYes — Sec. 42-7(b) says "any tract of land" and states no geographic limit
Wastewater, water and storm drainage plans not approved (42-7(c))Not stated — subsection (c) addresses the ETJYes, inside a utility district whose creation or enlargement the city consented to

Sec. 42-5 through Sec. 42-7. The criminal remedy is the one that stops at the city limits; the civil and utility remedies do not.

What the code says
The violation of any provision of this chapter outside the corporate limits of the city but within the city’s extraterritorial jurisdiction shall not constitute an offense, and no fine shall be applicable to the violation.
Houston Code of Ordinances — Penal provisions applicable — §42-5(b) · Read the full code

Inside the city, the clock runs daily

Sec. 42-5(a) does two things worth separating. It makes a violation of any provision of the chapter punishable under Sec. 1-6 of the Code — including, in its words, "the failure to do any act or perform any duty that is required herein," so an omission counts as much as an act. And it provides that each day a violation continues constitutes a separate offense.

That second clause is what changes the arithmetic. A continuing violation is not one penalty to be weighed against the cost of compliance; it is a penalty per day for as long as the condition persists. The schedule itself lives in Sec. 1-6, outside this chapter, and is not described here.

The provision with the most teeth is the quietest one

Sec. 42-7 does not punish anything. It simply directs three officials not to act — the building official, the utility official and the city engineer — and for most projects that is decisive.

The building official. Under Sec. 42-7(a), no building permit — and no other permit required to install any utility, public or private — may issue to serve a lot or tract inside the city with no properly recorded subdivision plat, or a development inside the city with no properly approved development plat. The words "or private" matter: routing around the city utility does not route around this.

The utility official. Under Sec. 42-7(b), no tract may receive any service from the city water or wastewater collection systems unless the applicant provides satisfactory evidence of compliance at the time of the application for service. The burden is on the applicant and the moment is fixed.

In the ETJ, one level up. Sec. 42-7(c) reaches the ETJ indirectly but effectively: within any utility district whose creation or enlargement the city consented to, the utility official may not approve wastewater or domestic water plans, and the city engineer may not approve storm drainage plans, until the chapter has been complied with for the tract the district serves. The ETJ carries no fine, but it can still be left without approved infrastructure plans.

The more restrictive rule governs. Sec. 42-9 makes Chapter 42 cumulative of other requirements imposed by ordinances and regulations of the city, and provides that to the extent of any inconsistency the more restrictive provision governs. Meeting the Chapter 42 figure does not discharge a stricter requirement located elsewhere in the Code. Note the reach of the provision: it speaks to ordinances and regulations of the city, so it settles conflicts within the Code and says nothing either way about private deed restrictions.

Common questions

Is it actually illegal to build without a plat in Houston?
Inside the city limits, yes — Sec. 42-5(a) makes any violation of Chapter 42 punishable under Sec. 1-6 of the Code, and states that each day a violation continues is a separate offense, so exposure accumulates daily rather than being a single fine. Outside the city but within the extraterritorial jurisdiction, no: Sec. 42-5(b) says plainly that a violation there "shall not constitute an offense, and no fine shall be applicable." That does not mean the chapter is unenforceable in the ETJ — the injunction and damages remedies in Sec. 42-6 expressly reach it, and so does the utility bar in Sec. 42-7(c).
What is the practical consequence of an unplatted tract?
You cannot get it served. Sec. 42-7(a) bars the building official from issuing a building permit — or any permit required to install a utility, public or private — for a tract inside the city with no properly recorded subdivision plat, or a development with no properly approved development plat. Sec. 42-7(b) then bars the utility official from letting the tract receive any city water or wastewater service unless the applicant produces satisfactory evidence of compliance at the time of application. For most projects this is the binding constraint, not the fine.
Can the city make me undo work already done?
It can ask a court to. Sec. 42-6 lets the city file suit either to enjoin a violation — or a <em>threatened</em> violation, so it need not wait until work has started — or to recover damages from the landowner "in an amount adequate for the city to undertake any construction or other activity necessary to bring about compliance." That second remedy is the cost of the city doing the corrective work itself, billed to the owner. Sec. 42-5(a) confirms these run alongside prosecution: conviction "shall never be a bar to any other remedy."
If two city rules conflict, which one applies?
The stricter one. Sec. 42-9 makes Chapter 42 cumulative of other requirements imposed by ordinances and regulations of the city, and provides that to the extent of any inconsistency the more restrictive provision governs. So satisfying Chapter 42 does not discharge an obligation imposed elsewhere in the Code, and where the two differ you meet the tighter figure. Note the wording covers city ordinances and regulations — private deed restrictions are not city rules, and they bind separately regardless.

This is how the code reads; confirm with the city — or ask a builder who's actually pulled this permit in Houston. The authoritative text is the Houston Code of Ordinances; permitting questions go to Houston Permitting Center.