7 Key Strategies for Construction in Coastal Regions
There is not a single strategy or solution for building structures along the coast. Any building design needs to be looked at holistically, not as individual design aspects or materials. When designed together and constructed as an assembly, all of the components of a building can create a safe, efficient, and resilient building. The following are 7 strategies for better construction along the coast.
1. Higher Finished Floor Heights and Site Design
Building at finished floor elevation well above the storm surge model can protect a building from hurricane and tropical storm surge flooding. This can be accomplished by building on pilings and, in some cases, by bringing the building pad up a few feet with fill material.
Another site design to pay attention to is landscape design, installation, and upkeep that should maintain the property’s ability to drain water away from the structure. Protecting coastal buildings from water is vitally important to the interior finishes and furnishings, and the structure’s long-term value.
2. Using Resilient and Efficient Wall Systems
Using resilient wall systems to build in coastal areas can protect both the structural integrity of the building, but also eliminate the chance for flying debris to penetrate the walls. Concrete wall assemblies like the Bautex Wall System should be considered for the inherent strength against high winds, but also for the lab-tested resistance to wind-borne missile debris.
These types of walls do not rely on sheathing for strength, and are far less likely to suffer catastrophic failure in a high wind event (like wood and metal light framed walls). Concrete walls don’t rot and rust in salt air, and are designed to be long lasting safe structures.
Bautex wall assemblies are also integrally insulated, providing both thermal mass and high R-value. Many coastal areas have hot summers, and efficient walls are a must when building in these regions. Resilient and high-performing walls must be one of the first considerations when building coastal structures for durability, safety, and energy efficiency.
3. Robust and Water-Resistant Roofs
Roofs have to be designed with low pitches to minimize the amount of wind pressure on the structure. Connections to the wall assembly should be designed to be robust and, if possible, to exceed the prescribed code. Having an adhered weather barrier on the roof sheathing will add protection against water penetration, should the roofing material become compromised during windstorm events. This type of redundancy not only creates a more efficient building, but can be the difference between water damage or not.
In most cases, roofs are the first part of the structure to be damaged along the coast during windstorms and hurricanes, and should be constructed to the highest quality and strength. Robust roofs on coastal buildings are necessary to protect the interior of the building, including all the furniture, appliances and other valuable personal property.
4. High-Performance Windows
Windows are often looked at for materials and colors, but should also be compared for performance as well. Buildings along the coast should be built with high-performing windows.
First, all of the window materials should be resistant to salt air and easy to clean. The windows should also have impact testing for windstorm and hurricane debris. Losing a window in a high wind event could result in flooding or an even worse structural failure when the enclosure is comprised and pressures are increased inside the structure.
Coastal areas are known for constant and long-term exposure to sun and heat. Therefore, the windows should be selected to combat those elements. When choosing windows, the solar heat gain coefficient (the amount of solar radiation allowed through the window) should be less than 0.20 and the U-factor (resistance to heat flow) should be less than 0.25. High-performing windows will contribute to a safer, easy to maintain, and more efficient structure.
5. Insulated and Sealed Attics
Putting HVAC units in unconditioned attic space should be avoided. Instead the thermal and air envelope should be at the roof line rather than the ceiling. Enclosing the attic space inside the building envelope lowers the temperature in this area and avoids exposing the air handler and HVAC ducting to heat, resulting in higher efficiency and more indoor comfort.
It is also easier and more effective to air seal the structure at the roofline than at the ceiling level, considering all of the light fixtures and other penetrations that are commonly installed in the ceilings of most homes.
6. Direct-Adhered Air and Moisture Barriers
Although not technically part of the HVAC system, the design of the building envelope needs to be considered as part of the indoor air quality and comfort delivery system. An effective air and moisture barrier is vital to the performance of any building located in humid coastal environments.
Fluid-applied and direct-adhered membrane air and moisture barriers offer the highest level of performance, especially as compared to mechanically fastened building wraps and felt paper. These air and moisture barrier systems will also perform better in windstorm events, protecting the building from water intrusion even after any façade or wall finish is compromised by high winds.
7. Supplemental Dehumidification
In conjunction with a well-designed HVAC system and a more airtight building envelope, supplemental dehumidification should be considered in coastal environments, especially along the Gulf Coast. Dehumidification systems are much more efficient at pulling moisture out of the indoor air than air conditioners. These systems allow the HVAC system to run much less often, especially in temperate months and when the building is unoccupied.
As a Texas-based company Bautex Systems, LLC is committed to high-performance building systems and design. To find out more about Bautex and how the Bautex Wall System can be a part of a robust coastal design go to bautexsystems.com.