Marshalltown (IA) High School: an 8,000-square-foot building with locker rooms, concession area, and a tornado-safe room.
As extreme weather events occur more often, storm shelter construction has become part of all kinds of community construction projects, like 911 call stations; emergency operations centers; fire, rescue, and ambulance stations; police stations; and K-12 school buildings with an occupant load of 50 or more, which are subject to the International Code Council (ICC) and the National Storm Shelter Association Standard for the Design and Construction of Storm Shelters.
When extreme weather threatens, individuals and communities need structurally sound storm shelters to provide protection. Precast concrete provides life-saving benefits when used in the construction of storm shelters.
Structural Integrity
Precast concrete provides the structural integrity necessary to provide trustworthy shelter from storms and extreme wind. Precast concrete is able to support loads independently without relying on adjacent support materials or soils.Extreme Wind Protection
In the Midwest in particular, we know the changing of the seasons can bring with it heavy storms, high winds, and tornadoes. Precast concrete can provide wind resistance up to 250 mph and resist damage from flying objects and debris, as evidenced in this video.Access and Entry
Precast concrete storm shelters can be efficiently designed to have access and entry points comply with ICC Standards.Fast Installation
Precast concrete components are scheduled for just-in-time delivery and installed by experienced erectors as pieces arrive. This helps keep projects on schedule and on budget.Thermal Mass
Precast concrete’s ability to moderate temperature inside a storm shelter keeps temperatures moderated and manageable for those inside.Ventilation
Because precast concrete offers design flexibility, ventilation openings are easily fabricated during the manufacturing process and can be installed to custom specifications.
Among the things designers must consider in the construction of storm shelters is the impact from flying debris and possible wind uplift. Precast concrete addresses both of these things.
El Paso Gridley Middle School with storm shelter: Gridley, Illinois
Every project offers its own unique goals and opportunities. Our team will ask questions and listen to your objectives and goals so we can apply the latest design and engineering techniques to your projects. We partner with our customers to find the right solutions for their projects.
We recently worked on a storm shelter as part of a school in DeKalb, Illinois with Richard L. Johnson Associates | Architects. The project includes precast concrete wall panels and double tees for the roof system.
“We just find the precast, with the durability and the weight of the precast with the concrete tees, makes sense as a good product for a storm shelter,” said Scott Johnson, Project Architect, Richard L. Johnson Associates | Architects.
When considering building materials, one of the main things that must be considered is that the storm shelter must be able to withstand 250 mile per hour winds. There are not many materials that can easily meet that requirement, but precast concrete can. Johnson likes the ease of use when it comes to precast concrete wall panels because there isn’t a whole lot of difference between designing and manufacturing the wall panels for a storm shelter than designing and manufacturing for any other type of building. The walls have to be a bit thicker, but otherwise it’s really just a matter of where the rebar and insulation goes, Johnson said, adding this makes precast a cost-effective building material.
Johnson added the components are both high quality and reliable as they are manufactured in the controlled setting of the precast plant. Additionally, because all precast components are custom made, our team will work with the design team to coordinate all openings and connection details to meet the needs of the project.
For the DeKalb project, our team worked with Johnson to ensure the best joint detail for the panels of the storm shelter. Wall panel joints larger than 3/4” require additional reinforcement to ensure nothing can penetrate the structure. To meet this requirement, the decision was made to step, or overlap, the walls to eliminate joints larger than 3/4”.
Additionally, when it comes to roofs for storm shelters, components have to be heavy enough that they don’t lift and must all be connected. The roof of a storm shelter can be constructed of either hollow core plank or double tees, depending on span and load. Double tees are ideal for long, column-free space and can provide spans of more than 100 feet. They also come in a variety of depths. Hollow core plank can span up to 60 feet depending on load. Roofs will always have 4” - 6” of topping as they are required to be heavily reinforced for storm shelters, said Tara Loomis, Sales Engineer for Mid-States Concrete Industries.
Precast concrete also provides “one stop shopping,” as the same precaster can provide both the wall and roof components, as well as complete all the shop drawings, detailing, and erection, decreasing the number of trades needed for the project.
When you partner with Mid-States Concrete Industries for your storm shelter project, we’re with you every step of the way - from preconstruction assessment, design and engineering support through construction and completion. It’s how we’ve done it for nearly 80 years and three generations of family leadership. We are committed to the success of your storm shelter (and other) projects.
“I think once you go through a storm shelter project and use precast for it, you have the knowledge of what to do,” Johnson said. “That’s why we don’t reinvent the wheel and try to do something out of another material. We’d probably stick with precast.”
To learn more about how we can help with your storm shelter project, contact our sales team at sales@msprecast.com.