Can Any Home Builder Build an Elevated House?

Not all custom home builders may have the expertise or experience required to build elevated houses. Constructing elevated homes involves specific engineering and design considerations that address flood risks and comply with local building codes. Builders need to be familiar with:

Specialized Construction Techniques

In the Tampa and St. Petersburg areas, elevated houses are commonly constructed using specific techniques to mitigate the risks of flooding and storm damage. Here are some of the primary construction techniques used:

Building on Stilts or Pilings

• Stilts (Pilings): This method involves driving wooden, steel, or reinforced concrete piles deep into the ground to support the structure above. This technique is particularly effective in coastal and flood-prone areas like Tampa Bay because it elevates the home above potential floodwaters and storm surges. The open space beneath the house allows water to flow freely without damaging the structure, providing natural ventilation that can help reduce energy costs.
• How It Works: The piles are driven into the ground to a depth where they can support the weight of the house through soil friction or end-bearing strength. This creates a stable foundation that is resistant to lateral forces from floodwaters and wind. The living area is then constructed above these piles, often with breakaway walls or flood vents at ground level to allow water to pass through without causing structural damage.

Pier and Beam Foundations

• Pier Foundations: Similar to stilt construction, pier foundations use concrete or stone piers placed strategically under the house’s load-bearing points. These piers elevate the home off the ground, protecting it from flooding while providing easy access to plumbing and electrical systems for maintenance.
• How It Works: Piers are typically made of concrete blocks or bricks and are spaced evenly under the house. Beams rest on these piers, supporting the floor joists and the rest of the structure. This method is advantageous for its cost-effectiveness and ease of repair compared to slab foundations.

Use of Breakaway Walls and Flood Vents

• Breakaway Walls: In some elevated homes, especially those built on stilts or pilings, non-load-bearing walls are constructed at ground level. These walls are designed to “break away” under pressure from floodwaters, allowing water to flow through without causing significant damage to the main structure.
• Flood Vents: These are installed in enclosed areas below elevated homes to allow water to enter and exit freely during a flood, reducing pressure on walls and minimizing potential damage.

These construction techniques not only provide protection against flooding but also enhance structural stability against strong winds and storm debris, making them highly suitable for homes in Florida’s coastal regions.

Local Building Codes and Regulations:

Building elevated homes in the Tampa and St. Petersburg areas requires adherence to specific local codes and regulations designed to mitigate flood risks and ensure structural integrity. Here are some key regulations that new home builders need to understand:

Florida Building Code (FBC) Requirements

• Base Flood Elevation (BFE): Homes must be built or elevated at or above the BFE, which is the computed elevation to which floodwater is anticipated to rise during a base flood. The FBC mandates that the lowest floor, including basements, must be at or above the BFE plus one foot or at the Design Flood Elevation (DFE), whichever is higher.
• Flood Design Requirements: In coastal high-hazard areas and Coastal A Zones, buildings must be elevated so that the bottom of the lowest horizontal structural member is above the BFE plus any required freeboard. This ensures that homes are protected from floodwaters.

Local Ordinances and Permits

• Floodplain Ordinance Requirements: Builders must comply with local floodplain management regulations, which include obtaining proper permits for construction in Special Flood Hazard Areas. Local building officials enforce these regulations, ensuring that homes meet elevation requirements even in areas where the BFE has not been established.
• Enclosed Areas Below Design Flood Elevation: Enclosed areas below the design flood elevation can only be used for parking, building access, or storage. These areas cannot be partitioned into separate rooms or finished for living space, and they must include flood openings to allow water passage.

Additional Considerations

• No Structural Fill: Fill used for structural support is prohibited; however, minor grading and fill may be used for landscaping and drainage purposes around buildings.
• Substantial Improvement and Damage Rules: If a property is substantially improved or damaged (costing 50% or more of its pre-damage market value), it must be brought up to current building codes and regulations. This includes compliance with elevation requirements.

FEMA Compliance and Local Permits

Builders must navigate the permitting process, ensuring compliance with FEMA guidelines and local ordinances. This includes obtaining necessary permits before construction begins.

When building an elevated house in the Tampa/St. Petersburg area, several permits and compliance measures are necessary, particularly from organizations like FEMA and local authorities. Here are the key requirements:

FEMA Compliance

• Floodplain Ordinance Requirements: Builders must adhere to floodplain management regulations, especially if the property is in a Special Flood Hazard Area (SFHA). This includes ensuring the home is built at or above the Base Flood Elevation (BFE).
• Increased Cost of Compliance (ICC) Coverage: If a home is substantially damaged, homeowners with an NFIP policy may be eligible for ICC coverage. This coverage can help pay for elevating the home to meet current floodplain management standards.
• Mitigation Grants: FEMA offers various grant programs, such as the Hazard Mitigation Grant Program, which includes funding for property elevations. Homeowners must apply through their local community, which then submits applications to the state and FEMA for approval before construction can begin.

Local Building Permits

• Site Plans and Surveys: Builders need to submit detailed site plans and topographical surveys as part of the permit application process in both Tampa and St. Petersburg.
  Building Plans: Complete building plans, including mechanical, electrical, and plumbing details, must be submitted for review. These plans must comply with the Florida Building Code and local ordinances.
• Flood Elevation Certificates: An elevation certificate is required to verify that the construction complies with floodplain management regulations. This document identifies the building’s elevation relative to sea level and confirms compliance with the BFE requirement.

Navigating the construction of an elevated home is a complicated process. Not all home builders are qualified to build these structures. Winway Homes is one of the few custom home builders that can help you. Contact us today to help you work through the process.