Alys Beach, Florida
Florida residents are well aware of the dangers posed by the coastal environment. Rising sea levels, flooding from rain events or tidal surge, drought-induced wildfires, and high wind events, including hurricanes, must be taken into consideration for community planning and sustainable development designs.
In 2018, Hurricane Michael served only to highlight the importance of code-compliant design and proper building practices in the Florida Panhandle. Residents were forced to address the realities and catastrophic effects of these environmental forces firsthand as result of this hurricane. While the concepts of resilient design may have been considered a luxury for some prior to this storm, its necessity was brought to the forefront after surveying the extent of the damage to Bay County.
Forward-thinking design professionals and building officials understand the importance of a progressive building code—one that is adaptive to the intensifying environmental forces. Infrastructure must mitigate the changes on a macro-level, and homes and buildings must be able to adapt on a micro-level. The inadequacy of the older, generally accepted minimum building practices seems apparent after subsequent storm events.
While the initial first-order damage is certainly the most visible and visceral, the second-order effects on the community are just as devastating. The displacement of the vital working population, exodus of businesses and industry, disruption of essential services, the unavailability of affordable housing and the stunting of any positive community momentum all serve to further iterate the important unseen benefits of resilient design implementation.
Understanding the importance of these detrimental environmental forces and their lingering second-order effects, the Alys Beach community has collectively resolved to elevate the minimum acceptable design standards proactively by adopting resilient design standards for its infrastructure, buildings and ancillary structures.
Begun in the early 2000s, Alys Beach established a formalized process to codify its commitment to achieve its highest potential well before the community ever faced its first hurricane threat. These enhanced standards are enforced through high-level design reviews by pre-approved design professionals including architects, structural and civil engineers prior to community approval or submission for construction permitting. The town requires prescribed design compliance checkpoint reviews during construction in addition to those required by the Walton County Building Official. Tail-end build specification compliance reviews are also required by the office of the town architect via a formal as-built certification by the structural engineer of record at the completion of the build. This certification along with the original construction documents, checkpoint construction review summaries and all pertinent supporting documentation are reviewed for completeness by a third party and maintained within the community’s records after the project certificate of occupancy.
Buildings and structures are required to be evaluated and designed to resist lateral forces including wind forces, seismic and flooding. Lots undergo a front-end, site-specific geotechnical evaluation to determine foundation types and support systems.
At the onset of the community master-planning, Alys Beach placed importance on the utilization of the site’s natural topography and historical hydrologic features within the contiguous 158-acre site.
Gulf-front properties were platted to place buildable surfaces landward of the beach coastal construction control line, the protective geometric formation of the beach dune network and the ecologically sensitive coastal protection zone.
This placement was a design strategy to minimize the propagation of over wash flooding to the interior of the property by impinging waves. This included the improvement and protection of the beach frontal dunes and re-nourishment of the stabilizing vegetation thereon during initial construction and site development. These naturally occurring landforms are vital features that act as the community’s first barrier against wave action and storm surge. This natural shoreline armoring is continually maintained by the community to provide a critical defense against event-based erosion, wave runup and resulting scour, loss of shoreline and dune retreat.
The Gulf-front homes themselves are designed and constructed to withstand these coastal exposures utilizing resistant construction per ASCE/SEI Standard 24-14, Flood Resistant Design and Construction, and the provisions of FEMA P-550, Recommended Residential Construction for Coastal Areas: Building on Strong and Safe Foundations. Each home uses a deep pile foundation system as an added measure to combat this level of exposure and ensure structural integrity and survivability even after extreme storm event-related erosion and scour. The resulting design of these homes is fully capable of withstanding the dynamic wave set-up and surge elevation of a 100-year storm event.
Site walls are designed to withstand wave slam and hydrodynamic loading as are other amenities such as pools. Pools and spas are also designed to withstand vertical hydrostatic loading and the effects of buoyancy to prevent displacement and impacts to adjacent structures.
For inland sections of Alys Beach, infrastructure designs focus on utilizing and improving the function of the on-site natural wetlands and maintaining the historic floodwater flow pathways as a priority rather than on maximization of unit build-out densities.
As part of the community standards for stormwater best management practices, Alys Beach was an early adopter of the Low Impact Development design standards. Commonly referred to as “green infrastructure,” these standards incorporate both traditional and unique stormwater treatment facilities including retention and detention ponds, bio-swales, rain gardens and vegetative natural buffers designed to function in concert with the surrounding ecosystem. Rather than using an unsightly centralized water impoundment area, which often requires extensive mass grading, this network of decentralized treatment zones and systems creates a treatment chain which closely replicates the natural hydrologic function of the pre-developed landscape.
The inland section’s infrastructure design uses and improves the function of the on–site natural wetlands and maintains the historic floodwater flow pathways.
This offers more opportunity for natural infiltration and percolation of rainwater which helps recharge natural groundwater levels, limits on-site pollutant transport, reduces environmental degradation, and controls flooding all while presenting a harmonious and complimentary addition to the natural surroundings.
It is true that most of these concepts are good design practices that are outlined within the technical requirements of the Walton County Development Code, FEMA guidelines and the Florida Department of Environmental Protection, but it is only recently that these concepts have been validated by regulatory bodies.
As an added measure for water quality treatment and flood attenuation and abatement, Alys Beach also requires each individual home site to mitigate their own impervious surface stormwater discharge rates and volumes prior to release into the community master stormwater treatment facility infrastructure. This limits post development stormwater flooding both within the community as well as safeguarding the surrounding developments downstream of any point-source discharge locations.
Great effort was made during the schematic layout of the infrastructure to maximize green spaces and integrate a network of walkways and bike paths through interconnected parks and block-hub courtyards. These are intended to encourage pedestrian traffic while staying in the community, reduce vehicular traffic and its emissions, and lessen the developments of the heat island effect.
Permeable surfaces have been used for street and parking surfaces to mitigate stormwater pollutants and runoff velocities. Many areas of Alys Beach use mixed lot designs varying from zero lot lines to more typical lots with conventional setbacks to the buildable surfaces. In order to minimize flood water buildup in areas of zero lot line homes, these green space and walkway corridors are essential. To the untrained eye, these only serve to provide clear site lines and pedestrian access to the Gulf, but in actuality, they serve as unobstructed water bleed-off points should the area be inundated during extreme rain or surge.
Permeable surfaces are used for street and parking surfaces to mitigate stormwater pollutants and runoff velocities.
Buildings and Ancillary Structures
Alys Beach became an early adopter and the first community to require full compliance with the standards of the Insurance Institute for Business and Home Safety (IBHS) Fortified HomeTM program “The National Standard for Resilient Construction.” This requirement was extended to all construction on the contiguous property. These requirements are above and beyond the standard requirements of the Florida Building Code and its source code, the International Building Code (IBC).
By participating in IBHS’ program, Alys Beach has enjoyed full access to the IBHS brain trust, its research and expertise. No differential design allowances have been granted for varying structure intended usage or occupancy within the community. Whether it is a multi-story, threshold level mixed use commercial building or a detached pool cabana, each and every element within the community is considered just as important within the critical chain of resiliency.
IBHS FORTIFIED Home requirements affect the design of a structure in varying ways depending on the geographic location of the building. Whereas California may place emphasis on seismic design and/or wildfire mitigation, Oklahoma may emphasize tornadic events and hail, and Minnesota may place emphasis on snow loading; the primary design focus of the Florida Panhandle is most certainly high velocity wind events via hurricane.
As part of the Fortified design standards, the minimum design wind storm event all construction in Alys Beach must be able to resist is 25 miles-per-hour higher than the standards set forth within the American Society of Civil Engineers’ ASCE 7-10, Minimum Design Loads for Buildings and Other Structures and the Florida Building Code. This requirement results in a design for each structure within Alys Beach being capable of resisting a 163 mile per hour wind force, which correlates to a Category 5 Hurricane on the Saffir-Simpson scale and a F3 tornado on the Fujita Tornado Scale. All structures must use in-situ windborne debris protection systems with rated impact resistant fenestration in all locations.
In addition to the primary effects of wind, Alys Beach requires fire-resistance-rated construction using fire-resistant materials and utilizing both passive and active fire protection strategies. Each home is constructed of concrete masonry units (CMU) or cast-in-place CIP exterior walls, wood and steel framed interior floor framing, CIP structural slabs for exterior porches, and concrete tile roofs with secondary waterproofing membranes. Each lot has a front-end site-specific geotechnical evaluation to determine foundation types and support systems.
Prescriptive design is not allowed. Buildings and structures are required to be fully structurally analyzed and engineered for the effects of gravity loads including dead loads, live load forces such as construction loads, occupancy loading, hydro-static and hydro-dynamic loads, flood loads, rain loading or ponding and wind uplift forces. As previously noted each structure is also required to be evaluated and designed to resist lateral forces including wind forces, seismic and flooding.
Enactment, Compliance Review and Certification
Alys Beach has a development review board with a town Architect to review all planned and proposed construction within the community. The community has approved design professionals and pre-approved builders who provide valuable input in each structure prior to breaking ground. All architectural documents submitted are accompanied by a structural design document package certified by a licensed Florida Professional Engineer to ensure design continuity.
As IBHS Certified Design Professionals, Terry Anderson, P.E., and I have personally collaborated on design teams as the structural engineers for over 250 separate projects in Alys Beach with Apex Engineering Group PLLC, formerly known as Anderson Engineers PA. As IBHS Professionals, our involvement extends into and includes the construction checkpoint reviews throughout the entire build cycle. These are important opportunities to provide guidance and contractor consultations in order to improve execution.
|Behind the Insurance Institute for Business and Home Safety’s Fortified Home Program|
The program outlines requirements for hurricane and high wind-resistant roof design. The program exceeds most building codes by improving renovated and newly constructed buildings’ performances against natural disasters and offers construction guidelines and standards to builders.
As part of the construction documents, an inspection frequency schedule and protocol is included for all new construction, which takes into account the specific building material sets, process and staging. Each checkpoint catalogues all necessary information with reports and records for official submittal to IBHS at the conclusion of the project for the compliance certification. It is required that an IBHS Certified Professional perform these reviews and submittals as a chain of custody cross-check.
This increased level of designed resilience, its processes and its resulting additional costs have not been met with resistance by the investors in the community. On the contrary, these fortified homes are considered and appreciated as a necessary extension of the community’s expression art through the elevated and exacting standards of resilient design. In an area of 30-A that routinely sees sale prices for homes around $1,000 per square foot on a routine basis, a secondary and no less important effect of the implementation of resilient community design has been the Fortified home designation becoming a mark of design excellence.
The once obscure moniker is now part of the local lexicon, spoken by realtors and design professionals. It correctly identifies the community as a flagship for the successful and cost-effective implementation of design standards that are ensured to meet the intensifying environmental threats of the future.
|Remembering Hurricane Michael|
Hurricane Michael made landfall in Florida on Oct. 10, 2018. The Category 5 storm caused catastrophic damage in the Panama City Beach area, which is about 25 miles from Alys Beach. Mexico Beach was one of the hardest hit areas with storm surge ranging from nine to 14 feet. The storm’s wind speed topped at 161 mph, according to the National Weather Service.
Alys Beach homeowners not only receive insurance rate reductions from the community’s IBHS participation to help absorb the added build costs associated with resilient design process, they also enjoy one of the highest resale rates and profit margins found along the scenic 30-A corridor. This return on investment is aided in no small part by the reputation this level of construction has garnered.
Since its implementation at Alys Beach, the resilient design standards put forth by the Fortified program have been made a marketable selling point for the community. In response, real estate in the immediate surrounding areas has developers and homeowners voluntarily choosing to design their projects to resilient standards in order to have their projects stand out within the market. While somewhat anecdotal, it has been noted that when prices are comparative, the FORTIFIED designation has been a great tie breaker for sale. This undoubtedly is due to the public becoming more attuned to the magnitude of costs associated with the mitigation of damage, even in code-compliant homes, after an environmental catastrophe.
It is easy to see the benefits, immediate and future, for the practical application of resilient community design when viewed through the lens that Alys Beach has provided. These increased standards not only create stronger structures, providing immediate higher levels of occupant safety, it has proven strategic to instill confidence in the community investors and project Alys Beach’s image of excellence. The process it has put in place ensures continued durability and protection for the artistic vision Alys Beach embodies and reinforces the concept of proactive and progressive professional design standards as an appreciated component of overall community resiliency.
This concept can be scaled for a range of neighborhoods and stand-alone developments using similar build characteristics, materials and techniques. Alys Beach serves a great example of how elevated design standards and resiliency can be achieved without sacrificing aesthetic. It shows how art, community master-planning, and its structures can complement each other, successfully contributing to effective design implementation of resilient developments. •
About the Author
Allen Barnes, P.E., is president of Apex Engineering Group, formerly Anderson Engineers, Santa Rosa, Fla.