Barndominium and barn builders in Blanco, Texas

The City of Blanco sits on the Blanco River around Blanco State Park, with US-281 running through and lavender farms and small ranches in the surrounding hills. It was the original county seat before the seat moved to Johnson City. Buyers are often looking for value and quiet on a few acres, with barndominium homes and shops leading the building mix.

Barndominiums and metal building homes lead, with workshops, equipment barns, and the occasional horse barn on the surrounding acreage. Practical, mid-range builds are the norm here more than high-end showpieces.

Custom barndominium construction around Blanco is practical and mid-range: a general contractor putting up a post-frame or steel metal home with a shop on a few acres near the river or out toward the lavender farms. Blanco County ties the septic permit to whether the tract was legally platted, so a Blanco barndominium contractor should ask about the plat before pricing the job, and a turnkey quote should say whether the septic system, the well and the driveway are in it.

How to check a builder before you sign

Inside the City of Blanco, city building permits apply, and the city's site development permit reaches into its extraterritorial jurisdiction (the Blanco city permits section below says which projects need it). Out in unincorporated Blanco County, there is no general building code, but the county ties the septic permit to subdivision platting: it will not issue a septic permit for a lot in a subdivision unless a final plat has been approved and filed of record. If you are buying a lot in an older or informal subdivision, confirm the platting status before you count on permitting a septic system. The Blanco County permitting page explains this.

Blanco County permitting reference

River-adjacent tracts bring floodplain considerations, and most of the county sits on the Trinity aquifer under thin limestone soils. Plan an aerobic septic unit, budget for a well drill, and engineer for roughly 105 to 115 mph design wind, more on the exposed rises.

Inside the city, a house, an addition or an accessory building starts with the residential permit application (revised July 2024), emailed with its drawings to City Hall at 300 Pecan Street, phone (830) 833-4525. Starting work before the permit issues can bring fines, a permitted project has 180 days to be finished, and every permit ends with a final inspection booked through Bureau Veritas. The submittal set asks for a plot plan at 1 inch to 20 feet showing setbacks, platted building lines and easements, floor and elevation drawings, engineered wind bracing plans, an energy compliance report, and a foundation plan with a design letter, sealed by a Texas engineer, saying the slab was designed for that lot's soil. A surveyor's sealed form survey has to be on site when the plumbing rough-in is inspected.

The rule most buyers miss is Section 5.9 of the city's Unified Development Code (adopted November 10, 2020). It applies both within Blanco's corporate limits and across the extraterritorial jurisdiction around them, and it bars development there until the city issues a site development permit, which follows a site plan review for nonresidential and certain residential projects. Barns, silos, livestock pens, sheds and other farm structures are exempt, and so are single-family detached homes unless the subdivision has private streets or a private amenity such as a pool or clubhouse. A commercial shop or an event barn is a nonresidential project, so it needs the plan. City staff may approve a small project, 3,500 square feet or less of disturbed ground counting parking, landscaping and the building pad, without the public notice step; larger ones go to the Planning and Zoning Commission and the City Council. An approved plan lapses if construction has not begun within two years, the owner pays the city back for any outside expert's review, and fill on a building site is capped at six feet deep unless the City Engineer approves more, with cuts held to six feet unless the Council allows deeper.

A new drive off a city street needs a driveway permit (form revised July 31, 2024) before any work in the right-of-way, filed by a contractor registered with the city, with a dimensioned plan that shows the culvert size. The concrete is inspected before it is poured. No driveway may be steeper than 15 percent, none may sit within 30 feet of a corner's curb return or 100 feet of a signalized intersection, a residential drive may not front an arterial, and a shared drive must be at least 15 feet wide with a recorded access easement for each owner. A drive onto a state highway, US 281 through town among them, needs its TxDOT permit before the city approves the plan.

The city's water and sewer tap application prices a water tap at $1,200 inside the city limits and $1,750 outside them, and a sewer tap at the same two amounts, all non-refundable and based on a 5/8-inch or 3/4-inch meter, with the owner paying the difference for anything larger. A residential account also carries a $195 deposit that covers the connect and inspection fees. Plan on it: the form says to allow 60 business days for the service to be installed, and it suspends every application for a new or larger connection or a main extension while the city's drought plan sits at Stage 4 or higher.

Ordinance 2026-O-005, passed April 14, 2026, sets water at $10.91 per 1,000 gallons whatever the tap size and sewer usage at 80 percent of the water rate, with base fees of $43.46 for water and $33.48 for sewer on a 5/8-inch meter, rising to $111.70 and $86.13 on a 1-inch meter. The availability fee for a property outside the city limits stays at $16.12.

A barndominium that keeps a private well alongside city water has one more rule. Under the city's water service agreement, the city inspects for cross-connections before new service begins, and the two systems may never be joined: the owner fits an air gap or a pressure-zone backflow preventer at the service connection and pays to test and maintain it, at $80 for a city backflow test. The Blanco-Pedernales district's well rules, including the 50-foot gap it keeps around a water utility's service area, are set out on the Johnson City page.

The National Weather Service forecasts the river at its Blanco River at Blanco gauge (BRBT2). Action stage is 14 feet, minor flooding starts at 18 feet, about 10,701 cubic feet a second, moderate at 24 feet and major at 30 feet. The service's own impact notes say that at 18 feet the picnic tables and parking areas nearest the river begin to flood, and at 21 feet Park Road 23 goes under. Ask a seller or surveyor where a riverside tract sits against those stages before choosing a pad.

The city's water resources assessment maps the smaller streams. Town Creek and Paradise Creek both rise north of town and run south into the river, and Durham Branch joins it south of town. A Soil Conservation Service pond on the Moore property controls the headwaters of Town Creek, but its releases can fill the whole 50-foot drainage easement through the Garden Oaks subdivision downstream, where occasional flooding of homes has been reported, so the city asks owners to keep fences, buildings and stored material out of that channel. The assessment also notes that the Paradise Creek crossing at 6th Street is a low-water crossing with a single 24-inch culvert, that public works staff call structural flooding from the town creeks rare, and that NOAA Weather Radio covers Blanco on 162.425 MHz.