Sandstone · New Braunfels, Texas

Home additions in New Braunfels, TX

Sandstone Construction & Remodeling builds room additions, primary suites, garage conversions and casitas in New Braunfels and across Comal County. Inside city limits, plans are checked against New Braunfels’ amended version of the 2021 International Residential Code, starting with a site plan and a foundation plan. River lots may need floodplain approval, and hillside lots raise rock and grade questions.

Call (830) 400-4369

Office hours 8 AM–11 PM daily

What the city asks for

The City of New Braunfels requires a residential permit to enlarge a home, and accepts addition applications online. Its Residential Addition Application Checklist (July 2022 edition) includes:

A scaled site plan marking the new footprint, setbacks, easements, lot lines, existing buildings and any new flatwork.
A foundation plan under chapter 4 of the 2021 IRC. Above 500 square feet, or when foundation repair is involved, it must be engineered and sealed by a Texas professional engineer.
Wall bracing plans, also engineered above 500 square feet.
Roof and ceiling framing plans, plus beam and header details wherever an existing wall is opened.
Mechanical, electrical and plumbing plans if the room has them, an erosion control plan, and REScheck-style energy compliance paperwork.

Every contractor, the general contractor too, needs city registration. The application goes in before work starts, and the permit is issued to the contractor of record. For the wider picture, see New Braunfels remodel permits.

A New Braunfels mailing address doesn’t always mean city limits. In unincorporated Comal County, the County Engineer’s Office on David Jonas Drive handles floodplain development, septic design review and driveway permits; around McQueeney and much of Lake Dunlap, unincorporated lots instead go to Guadalupe County, whose Environmental Health Department handles septic and floodplain permits. Confirm jurisdiction first.

River and creek lots

Floodplain rules near the Guadalupe and Comal

Your lot’s FEMA flood zone settles this, not how close the water looks. In a Special Flood Hazard Area an addition counts as development, so it needs a city floodplain development permit, separate from the building permit, before construction.

The city’s floodplain application puts the lowest floor, with its utilities, 2 feet above base flood elevation, shown on an elevation certificate prepared by a land surveyor or engineer. An addition inside a regulatory floodway needs a No-Rise Certificate. If the addition’s cost, counted with earlier improvements, reaches half the structure’s market value, the whole house must meet current floodplain rules. The new rooms can’t be used until a Certificate of Compliance is issued.

Get a flood zone determination before sketching, especially on river streets near Gruene or lake lots around Lake Dunlap and McQueeney. In unincorporated areas, county floodplain rules apply instead.

Slopes and limestone on Hill Country lots

Toward Canyon Lake, in Bulverde and Spring Branch and on many New Braunfels streets, lots fall away from the house and limestone sits near the surface.

Grade. The new floor must meet the old one, so on a falling lot the downhill side of an addition can stand well above the dirt. Deeper grade beams, a stepped foundation, a pier-and-beam floor or a retaining wall may be the answer, and each one changes the engineering.

Rock. Shallow limestone bears weight well, but trenching beams and drain lines through it can take a rock saw or hammer. A soils report or an engineer’s site visit before design beats finding out mid-dig.

Runoff. Hill Country downpours need a path. Shape swales and place downspout outlets so water coming down the slope passes around the addition.

Where old meets new

Tying into the roof and the slab

Roof. Matching the existing pitch and overhang usually looks right and drains simply. If a matching ridge would climb too high or run into an upstairs window, a lower hip or shed roof can work instead. Valleys and flashing at the joint need room to shed water.

Slab. The foundation plan shows how the new slab attaches to the old, often with steel dowels epoxied into the existing beam. Floor heights, the vapor retarder and under-slab plumbing are set and inspected before concrete is placed.

Systems. Confirm early whether the heating and cooling equipment can carry the added square footage and whether the electrical panel has spare capacity.

Exposed timber wall and roof framing on a house under construction

Other ways to add room

Garage conversions and casitas

The city lists converting a garage and putting up an accessory building among the projects that need a residential permit.

01 / Inside existing walls

Garage conversion

Garage slabs usually sit lower than the house and slope to the door, so the floor gets built up. The door opening becomes framed wall with a window, and the room needs insulation and conditioned air. The city’s remodel checklist requires energy compliance when the building envelope changes.

02 / Attached

Room or primary suite

A bedroom wing or primary suite follows the full addition checklist and the roof and slab tie-in above.

03 / Detached

Casita or guest house

A casita leaves the house intact, but water, sewer or septic, and power must reach it, and zoning and setbacks shape where it stands and how it is used. Planning a rental? Read short-term rental remodels. On a county septic lot, bring in the county’s environmental health staff early.

Questions to settle before design

Is the lot inside city limits, and does any of it fall in a FEMA flood zone?
Do you have a survey or plat showing easements, setbacks and any septic field?
Does an HOA need to approve plans before the city sees them?
Which existing room becomes the path into the addition, and what does it give up?
Would a covered patio or a whole-home remodel solve the problem without new square footage?

Start with a phone call

Call (830) 400-4369 with your address, rough measurements and a photo of the wall you want to build from. Office hours 8 AM–11 PM daily.

Home addition answers

Common questions

Do I need an engineer for a home addition in New Braunfels?

Above 500 square feet, yes: the city’s addition checklist then requires foundation and wall bracing plans engineered and sealed by a Texas professional engineer. If the job includes foundation repair, the foundation plan must be engineered whatever the size. Engineered details may also be required where a load-bearing wall is changed.

Can I add on to a house near the Guadalupe or Comal River?

Often, with extra steps. In a FEMA Special Flood Hazard Area, a city floodplain development permit is needed alongside the building permit, and its application calls for an elevation certificate and a lowest floor 2 feet above the base flood elevation. If an addition plus earlier improvements costs half the structure’s market value or more, the whole house must meet current floodplain rules.

Does a garage conversion need a permit in New Braunfels?

Yes. The city names converting a garage among the projects that need a residential permit. The plans should show how the floor is raised, the door opening framed in, and the room insulated, heated and cooled.

Is a detached casita permitted the same way as an attached addition?

Not exactly. The city lists an accessory building as its own residential permit type, and zoning, setbacks and utility runs weigh more on a detached structure. In unincorporated Comal County, the County Engineer’s Office reviews septic designs and floodplain development.