Our insulating concrete form (ICF) is made from expanded polystyrene (EPS) molded into lightweight foam blocks. The foam itself provides excellent insulation with an R value of R-21. The R-value of EPS remains constant. (R-values of traditional fiberglass insulation decreases when the material is wet or damaged.)

In addition to the inherent insulation value of the EPS foam, the thermal performance is enhanced by the thermal mass effect of the concrete and the absences of air infiltration in walls constructed with ReddiForm. The combination of the heavy concrete mass and the foam surrounding it stores heat in the winter. In the summer it moderates the rise in the indoor temperature as the outdoor temperature increases during the day. In the cool of the evening, heat stored in the concrete is radiated back to the outside atmosphere.

We’ve chosen to manufacture ReddiForm with Modified Expanded Polystyrene (EPS) foam because of its fire performance, structural performance, and environmental advantages. Modified EPS contains no formaldehydes or toxic chemicals, and uses fewer resources to manufacture than other insulation products. EPS provides you with superior thermal performance to better insulate your buildings, and no harmful CFC’s have ever been used to manufacture it.
You can now recycle your jobsite scrap through a network of manufacturers, re-processors, and retailers across the country. EPS is a valuable resource than can be remanufactured into foam packaging or made into an amazing array of polystyrene products from office supplies to video cassette cartridges.

To locate your nearest EPS collection site, call the RECYCLING HOTLINE at 1-800-944-8448. Please recycle jobsite scrap.

Expanded Polystyrene (EPS) Facts

EPS is manufactured from expandable polystyrene beads containing a hydrocarbon blowing agent and a flame-retardant additive. It is a closed cell, lightweight, resilient, foamed plastic composed of hydrogen and carbon atoms. There are two common types of polystyrene foam, Extruded Polystyrene or XEPS (popularly known by it's Dow trademark, Styrofoam) and Expanded Polystyrene (EPS). Both expanded polystyrene and extruded polystyrene are used extensively as thermal insulation in industrial, commercial and residential construction.

During the processing of EPS, steam heat softens the beads and causes the blowing agent to expand to produce moisture-resistant multi-cellular particles which increase in size up to 40 times their original volume.

Following a period of stabilization, during which time the beads lose their moisture, the blowing agent condenses out and air diffuses into their cellular structure, the pre-expanded beads are molded into ReddiForm blocks.

The benefits of EPS thermal insulation products are it's lightweight, has stable long term thermal resistance, no R-value loss over time (Source: 1985 Study conducted by Structural Research, Inc. for NRCA, MRCA, and SPI) , and cost effectiveness when compared to other rigid board insulations on the basis of R-value.

Is EPS a water, vapor or air barrier?

EPS is considered water resistant and vapor permeable and at the density and thickness of ReddiForm blocks, the material acts as both a vapor retarder and an air barrier. This characteristic essentially moves the dew point to the exterior side of the concrete wall, minimizing interior humidity in the summer, and at the same time eliminates air infiltration in all seasons which is recognized as a major cause of R-value loss in fiberglass insulation.

Air exchangers or heat recovery ventilation systems are highly recommended!

Is EPS foam toxic?

EPS is an inert, non-biodegradable organic plastic foam which will not rot and is highly resistant to mildew. According to National Bureau of Standards Combustion Tests, data collected from seven labs concluded that under the worst case fire scenario, fumes from EPS are no more toxic than those from wood (Douglas Fir).

Is EPS Flammable?

The requirements of all the major code organizations for foam plastics is that they have a flame spread of not more than 75 and a smoke development rating of not more than 450. The foam used in ReddiForm has a flame spread rating of 15 and a smoke development rating of 125 based on ASTME84-87 tests, well below the code requirements.