THE POLYSTEEL FORM®

WHAT IS IT?

Our Polysteel Form® is a new and innovative polystyrene and steel form for the construction of super-insulated concrete walls. It's core design creates a reinforced concrete wall based on traditional post and beam construction (Figure 1.3), and the stay-in-place expanded polystyrene insulation provides a stable foundation for the attachment of wall coverings, in addition to providing a superior effective R-value rating.

As a form for wet concrete, the Polysteel Form® is significantly stronger than other EPS forms. Polysteel Forms® are held together with five unique attachment and reinforcement members. Ten 1" X 10" galvanized steel attachment strips, five located on each side, are spaced at 12 inches on center. These strips visually define where the vertical concrete posts are located within each Form. Each strip is rigidly anchored to the concrete by the galvanized expanded steel. Self-tapping drywall screws, or other self-tapping sheet metal screws, are the ideal method for attaching any type of interior or exterior wall covering to these strips. Drywall, lathe and plaster, siding, stucco, brick veneer, etc., can all be applied to Polysteel Forms® to achieve whatever finished look you may desire.

American Polysteel Forms® are currently manufactured in two core sizes, 6-inch and 8-inch. We also offer factory pre-cut corners, matched and bound for assembly in the field.

The drawing below (Figure 1.1) illustrates the dimensions of these two basic forms:

Figure 1.1

POLYSTEEL FORMS®
PRODUCE STRONGER CONCRETE WALLS

American Polysteel Forms® provide the ideal conditions for curing concrete. This allows the concrete to to achieve the greatest strength possible, creating a Polysteel® wall that outperforms traditional construction methods.

Concrete is made possible because of the chemical reaction of cement and water. This reaction, called hydration, requires time and favorable conditions of temperature and moisture.

Water is required initially to begin the process by making a cement paste. Once the compound is formed, hydration starts and continues as long as moisture remains. The process stops when moisture is removed by heat and evaporation, but can be restarted by adding moisture, even though this is undesireable.

The chart in Figure 1.2 shows the compressive strength that is formed under various conditions of hydration. When the hydration process is controlled for the first 28 days, that is, when moisture is continually available in the mass, 100 percent strength is obtained. If hydration is continued beyond that point, strength continues to increase, exceeding 125 percent after 180 days. However, notice that various degrees of strength are obtained if improper methods of curing are used.

Chemical action in the concrete mix can be sustained by:

1. Keeping the concrete wet 24 hours a day, using water and hoses.
2. Applying a plastic cover over the concrete, trapping the moisture within.
3. Covering the concrete with burlap, which is kept wet.
4. Covering the concrete with fresh hay, which is kept wet. This method also aids against freezing.

As you can see, the self-contained environment created by the Polysteel Form® provides the ideal conditions for hydration to continue up to, and beyond, 180 days. This creates a compressive strength in the concrete that exceeds 125 percent of the strength provided by conventional concrete curing methods.

Figure 1.2

POLYSTEEL FORMS®
PRODUCE STRONGER CONCRETE

The illustration below (Figure 1.3) reveals the concrete post-and-beam structure created within a 6-inch Polysteel Form®. This structural design, combined with the superior strength of the concrete cured in our form, makes Polysteel® walls stronger.

Figure 1.3

Walls constructed of Polysteel Forms® provide a shear wall strength of up to 3,500 pounds per linear foot.

Dean Johnson
Hometime - "House with Character"
Public Televisoin Series, 1995