Building Flood-Resistant Homes in Houston with Bautex ICFs
In response to the tragic flooding caused by Hurricane Harvey in 2018, Houston amended their Floodplain Code of Ordinances. Builders and architects of new construction and substantial improvements projects in Houston must design in accordance with both the City of Houston’s Code of Ordinances for Floodplains and the American Society of Civil Engineers 24 (ASCE 24).
Critical components of a successful flood-resistant design include elevated structures, materials that can get wet, and design assemblies that quickly dry when exposed to moisture, like Bautex insulated concrete forms (ICFs).
Hurricane Harvey Ravages Houston
On August 25, 2017, Hurricane Harvey, (a Category 4 storm) hit Houston. The storm centered over or near the Texas coast for four days, producing historic amounts of rainfall of more than 60 inches, resulting in catastrophic flooding over two-thirds of Houston. Furthermore, Harvey produced 52 tornadoes, about half of which occurred near and south of the Houston metro area.
The National Hurricane Center reports that Hurricane Harvey caused $125 billion in damage and 68 deaths. Hurricane Harvey damaged more than 204,000 homes and apartment buildings in Harris County, and the Greater Houston Builders Association reports Harvey destroyed an estimated 30,000 homes in Houston.
Houston Rebuilds with Flood-Resistant Design
Hurricane Harvey devastated the Houston area. However, it created the opportunity for Houston to bounce back and rebuild with more flood-resistant structures that will survive future hurricanes.
In response to the extensive flooding during Hurricane Harvey, the city of Houston reviewed their local floodplain regulations for new construction and substantial improvements, which resulted in amendments to Chapter 19 (Floodplains) of the City of Houston Code of Ordinances. The purpose of these amendments, which went into effect September 1, 2018, is to ensure permitting regulations that stop or mitigate flooding in Houston. The changes in the floodplain code of ordinances affected the regulated areas, elevation requirements, and zero net fill.
Floodplain Regulated Areas
As of September 2018, Houston requires enforcement of floodplain development permits and guidelines for properties within the 500-year and 100-year floodplain and floodway. Before September 2018, the requirement for floodplain development permits and guidelines was for properties that were partially or entirely within the 100-year floodplain and floodway.
Importantly, when building within a regulatory floodplain and Special Flood Hazard Area (SFHA) in the City of Houston, a contractor must first obtain a Floodplain Development Permit before drawing a plat map or getting a demolition, building, or site permit. The City of Houston’s Floodplain Management Office (FMO), reviews and enforces the permits, which carries a fee ranging from $110 to $2,697.
Floodplain Elevation Required
As of September 2018, the finished floor elevation (FFE) of a proposed building or addition increased to at or above the 500-year base flood elevation (BFE) plus 2 feet. Before September 2018, the FFE only needed to meet or exceed the 100-year BFE plus 1 foot.
Zero Net Fill in Floodplains
As of September 2018, Houston mandated a zero net fill regulation for earthwork, paving, building, and grading within floodplain regulated areas.
What is Zero Net Fill?
Both fill that is added to reach the new elevation and the structure adds to the water displacement and cause the floodplain width of the property to increase. Zero net fill requires removing land equal to the fill and build amounts so to offsets the volume of water and decrease the floodplain width, which will help protect the structure during a flood event.
Building a Flood-Resistant Structure in Houston
In Houston, the design of a flood-resistant structure must be compliant with the City of Houston Code of Ordinances for Floodplains and the American Society of Civil Engineers 24 (ASCE 24). An effective flood-resistant design includes elevated structures, materials that can get wet, and design assemblies that easily dry when exposed to moisture, like Bautex Blocks. While foundations within the floodplains of Houston continue to allow any foundation in the 100-year or 500-year floodplain, Harris County current floodplain regulations specifies pier & beam.
The Bautex Block is a moisture- resistant composite material of EPS foam beads and cement. Application of the Bautex AMB 20 Air and Moisture Barrier over the Bautex Blocks prevents moisture from getting into the walls.
Bautex Block are Mold-Resistant
The water resistance and inorganic composition of the Bautex Wall System prevent the growth of mold and mildew in a home. No mold and mildew on the wall mean less clean up than a wall built with non-water resistant, organic materials, like wood framing and oriented strand board (OSB) used for exterior wall sheathing.
Bautex Blocks are Durable
Bautex Block reinforced concrete construction does not degrade when wet and maintains its original durability during and after a flood.
The Bautex Wall System has all the vital elements of a flood-resistant wall: the durability and strength to resist water intrusion before and after a flood, water‑, mold‑, and mildew- resistance, and permeability. Bautex walls are also quick and easy to clean after a flood.
Houston’s amended Floodplain Code of Ordinances aim to protect homes from flooding disasters. Builders and architects that design in accordance with both the City of Houston Code of Ordinances for Floodplains and the American Society of Civil Engineers 24 (ASCE 24) will ensure the integrity of the structure against excessive flooding.
A successful flood-resistant design includes elevated structures, products that can get wet, and design assemblies that dry fast when exposed to water, like Bautex insulated concrete block.