Gravette School District reviews ICC 500 storm-shelter classroom addition; 5-vs-6 classroom choice hinges on cost

Mike Spathe, an architect with Build Architects, and Crossland Construction representatives presented conceptual plans for a classroom addition at Gravette High School that would be built as an ICC 500-rated storm shelter.

The district is weighing a 6-classroom addition against a smaller 5-classroom option. "This configuration here represents a 6 classroom addition," Spathe said, describing a layout that would make the six classrooms, the corridor and two restrooms part of the shelter envelope. He said storm-shelter exterior walls would be 12-inch concrete masonry unit (CMU) in order to meet ICC 500 resistance requirements: "We have to have 12 inches thick because we have to be able to resist 250 mile an hour winds and 90 mile an hour projectiles as part of the ICC 500."

Crossland’s preconstruction representative, Jason, said detailed budgeting is still in early stages but gave ranges the board used to compare options: for a 6-classroom/ICC 500 addition, Crossland estimated a conceptual cost in the roughly $4.3 million to $5.1 million range and said they were currently tracking just under $5 million; the 5-classroom option was estimated in the roughly $4.0 million to $4.6 million range. Jason added that the difference between the two layouts is on the order of 900 square feet.

Architect and contractor teams advised against using precast panels for the addition because of cost and appearance differences with the existing high school. Spathe said the team recommends conventional CMU construction with masonry veneer to achieve the closest match to the existing building. He warned that some openings and penetrations will require additional protective measures: "Every penetration that comes into or goes out of the storm shelter that's greater than 2 inches has to have missile protection, and those shrouds are not cheap." He referenced another district project that had about $120,000 in steel shrouds to protect penetrations.

Because the addition would be composed of classrooms, corridors and restrooms rather than a single large open space, the design will require mechanical ventilation that must function for two hours under ICC 500, and that ventilation equipment will require generator backup. Spathe noted generator enclosures that meet ICC 500 standards are available but can be costly; the district could also design a conventional enclosure and submit it for third-party review.

Site utilities were discussed: the team identified a storm sewer and a sanitary sewer run beneath or near the proposed addition and said, based on a site walk, the lines appear far enough below grade or sufficiently offset to allow construction without major rerouting. The designers said the conceptual addition tracks at about 8,500 square feet at this stage of design.

Board members asked for time to review the detailed, filled-in policy/options documents when available. The board did not vote on a final design tonight; members said they expect to take up a decision at the June 16 board meeting and noted that bonds and final construction numbers expected the following day will affect the budget available for the project.

Spathe and Crossland representatives emphasized that the design is still conceptual and that final square footage, finish options, and budget will change as the project moves through design and third‑party review.

The discussion took place during the superintendent’s report and a facilities presentation; no formal design approval or contract award occurred at this meeting.