Introduction to ThermoBlock
This form ensures the building owner doesn’t pay for more structural cost than the particular building requires. This factor also means that most projects require a registered engineer to analyze the building’s structural requirements and establish minimum standards of needed grouting and reinforcement. The blueprints are typically stamped by the engineer as well as the report prepared by the structural engineer. This often makes the process of permit application much faster and easier than with other ICF systems. ThermoBlock meets all requirements of structurally reinforced masonry construction as described in the appropriate section of the ICC-ES Report.
Most engineering reports call for a minimum of 3000 psi concrete to be used to grout the wall system. 3/8” aggregate in the design mix is recommended to improve flow and accommodate pumping of concrete. Most ready-mix concrete companies have a design and mix called “block grout” that works well for ICF construction. [Verify that design strengths match or exceed engineers requirements.]
Although grouting and reinforcement schedules vary with ThermoBlock wall systems, there are some design criteria that tend to repeat in many applications. In above-grade walls, vertical concrete columns typically occur on 16” centers.
This allows ThermoBlock’s patented Internal Bracing System (IBS) to be installed in alternating cells providing alignment, bracing and fastening on 16” centers as well. These vertical cells containing the IBS can be filled with concrete, ground-up foam or other types of insulation, but are typically left empty, thus providing a vertical chase in the wall for plumbing and electrical retrofit. Horizontal bond beams that tie the vertical columns together are typically located on 4’ centers within the wall, above wall openings, such as doors and windows, and at floor intersections and top plate of wall. These horizontal beams usually accommodate attachment of floor and roof systems to ThermoBlock wall systems via anchor bolts. These anchor bolts, when tied to vertical re-bars provide floor to roof attachment of roof framing systems giving the wall system superior wind uplift and shear capabilities. When tied to horizontal re-bars they provide ledgering capabilities that will support heavy live and dead load flooring/ roofing systems.
Typical reinforcement steel schedules in above grade applications are #4 vertical and #5 horizontal. While these schedules typically accommodate most walls above grade, below grade applications, long, high walls and other nontypical walls may require heavier re-bar. It is preferred to utilize a single, larger diameter re-bar versus multiple smaller re-bar. This aids in the consolidation of concrete in the wall system allowing the concrete to flow easier and cover more thoroughly. Vibrating the concrete in the all system is typically not necessary if the proper slump and design-mix of concrete is used.
It is important to understand that ThermoBlock is a stay-in-place insulated concrete form. The blocks themselves are not structural members and the IBS stud provides no structural support other than attachment of interior and exterior finishes. The basis for the structural strength of the wall system is steel reinforced concrete construction. This type of construction offers superior strength when compared to conventional wood frame construction and provides a building that is cost competitive initially and pays dividends to the owner with years of reduced energy costs and building maintenance.