Applications, Design & Construction Considerations for EPS Geofoam

Originally posted on CE News online in Progressive Engineering

Geofoam: A lightweight fill alternative

Pacific Bridge

To widen the Pacific Street Bridge over I-680 in Omaha, Neb., Hawkins Construction excavated the soil between the existing abutment wall using EPS geofoam as lightweight backfill for the bridge approach.

Geofoam is a rigid, engineered, lightweight fill material typically made of expanded polystyrene (EPS). For fills, a key advantage of EPS geofoam is its low weight — approximately 1 to 2 percent the weight of soil. Typical densities for EPS fill are between 0.7 and 2.85 pounds per cubic foot, therefore maintaining a predictable compressive strength that is suitable for many structural applications (see “Geofoam physical properties”).

Today, geofoam is fully recognized and accepted as a lightweight fill alternative and has seen increased use in commercial and residential applications. Since the first installation of geofoam in 1965 (see “A short history of geofoam”), numerous projects around the world that have relied on the material to solve construction problems.

Given EPS geofoam’s low weight, strength, and ease of use, more project teams are using it to solve regular construction challenges in five basic applications.  Read the full article featured on CE NEWS as our Geofoam Specialist, Nico, discusses:

  • The five basic applications and specific project examples:  1.)  Lateral load reductions on structures  2.)  Soft soil remediation  3.)  Slope stabilization  4.)  Lateral and dead load reductions over buried utilities  5.)  Lightweight structural void fill.
  • Geofoam physical properties
  • Short history of geofoam
  • Construction considerations
  • Cost saving advantages

Expanded Polystyrene (EPS) Geofoam Vs. Traditional Fill

Public Works_2013 cover photo

2013 Public Works Magazine

Developed in the 1960’s as an engineered geotechnical material, expanded polystyrene (EPS) geofoam performs well in numerous applications and was designated by the Federal Highway Administration (FHWA) as a “priority, market-ready technology” in 2006.  As outlined in the spring 2013 Public Works magazine annual reference “Manual”, geofoam is 100% recyclable and non-toxic and it’s lightweight fill is used to reduce vertical stresses beneath embankments and lateral stresses on retaining walls, abutments, or foundations.  

Read more in the Public Works magazine:

  • geofoam defining properties
  • how to choose a geofoam supplier
  • per-cubic-yard costs of various fills
  • public works applications
  • key benefits
  • EPS goefoam cost vs. other fills

Read more on Geofoam:


Nico Sutmoller, Insulfoam Geofoam Specialist

Nico Sutmoller, Insulfoam Geofoam Specialist

Contact Nico Sutmoller, Geofoam Specialist

Connect with Nico on LinkedIn

Rigid Foam…not just for insulation


EPS geofoam

The same material that many contractors use to insulate walls and roofs—expanded polystyrene (EPS)—can help reduce lateral loads on building foundations and retaining walls. EPS geofoam is a lightweight fill that allows for the use of thinner walls, with less material, as well as a reduction in labor needed for concrete forming or the installation of segmented retaining wall blocks.

EPS geofoam has the same composition as EPS insulation, but is formed into blocks, rather than sheets. As a fill material, a key advantage of EPS is its ultra low weight—approximately 100 times lighter than soil (one to three pounds per cubic foot compared to 110 to 120 pounds for soil). EPS geofoam enables contractors to backfill against walls and foundations, replacing the heavy soil wedge customary with traditional fill materials.

Read more as detailed by Nico Sutmoller, Geofoam Specialist, in Walls and Ceilings. Nico outlines geofoam benefits, applications and where engineers often specify EPS geofoam and why.

Read full article here…

Nico Sutmoller, Insulfoam Geofoam Specialist

Nico Sutmoller, Insulfoam Geofoam Specialist

Contact Nico Sutmoller, Geofoam Specialist

Connect with Nico on LinkedIn

Geofoam Offers Performance and Efficiency for Bridge Reconstruction

Modern Contractor Solutions Magazine

Modern Contractor Magazine, April 2009

Originally published in Modern Contractor Magazine, April 2009

Full article (pdf)

Known as one of the Top 10 High-Tech metropolitan areas in the nation (as cited by Newsweek magazine), the city of Omaha, Nebraska, leads the nation by pursuing the most innovative technologies in virtually every field imaginable, not the least of which is road construction.  With more than 100 road construction projects currently under contract, the Nebraska Department of Roads (NDOR) strives to utilize the most effective and efficient construction products in its continuous improvement of the state’s road structures.

That is why, when NDOR officials decided to reconstruct the Pacific Street Bridge, they chose to use expanded polystyrene (EPS) geofoam for the below-grade void fill portion of the construction project.  By spring of 2008, Pacific Street, which provides commuters with convent access to and from downtown Omaha, was experiencing significant traffic congestion, decreasing the ease and efficiency of local commutes.

The Pacific Street Bridge, which spans Interstate 680, experienced the heaviest congestion, affecting the flow of both local and regional traffic.  It became apparent to NDOR officials that this situation required a remedy that would not only be effective in streamlining the flow of traffic, but could also be completed in a short time frame.

The NDOR decided to widen the bridge by adding one lane, while maintaining the current length of the bridge.  Construction, which was managed by Hawkins Construction Company, a local Omaha-based construction contractor, began in March 2008.

The existing 2:1 slope protection was removed and replaced by abutment walls allowing room for t he needed extra lane

Pacific Street Bridge, Nebraska:  The existing 2:1 slope protection was removed and replaced by abutment walls allowing room for the needed extra lane

In order to build an additional lane without lengthening the bridge, Hawkins had to first construct abutment walls at each end of the bridge.  To avoid creating excessive lateral pressures on the new abutments, a lightweight void fill material was needed for filling in the embankments.  Because of this requirement, the NDOR chose to use geofoam for this portion of the application.

After comparing a number of geofoam manufacturers, Hawkins Construction chose to use geofoam manufactured by Insulfoam, the nation’s largest manufacturer of block-molded expanded polystyrene.

“It was vital that we use a product that would not increase the amount of lateral load placed on the new abutments,” said Omar Qudus, NDOR Geotechnical Engineer.  “We chose to use geofoam because it would do just that, and would enable us to fill the embankments while still being able to build the additional lane.”

As this was the NDOR’s first specification of geofoam, Qudus and his team consulted multiple geofoam manufacturers in order to ensure that the geofoam was used correctly and in a way that would enhance both the performance of the bridge and the efficiency of the construction.

“We talked to a number of geofoam manufacturers,” says Qudus, ”because we wanted to make sure that we were using the geofoam product correctly. Insulfoam provided ample feedback and a detailed specification of how InsulFoam® GF can be used in this type of application.”

The construction project required a total of 2,045 cubic yards of type 15 EPS low-density geofoam blocks that were installed as void fill at the bridge abutments.

After pouring the abutment walls, the Hawkins crew installed the geofoam blocks, which not only provided easy handling, but also sped up the installation process. The use of geofoam eliminated both the need for surcharge and the settlement that is experienced with typical fill products, such as soil.

“We used geofoam for this project because we did not have enough time for both the surcharge and settlement that are typical with the application of traditional fill products,” says Qudus.


Pacific Street Bridge, Nebraska

Hawkins’ on-site supervisor, Lance Winkler, agreed that the use of geofoam significantly reduced construction time. “With traditional fill products, we typically backfill with sand at 8-inch increments and then compact; with geofoam, we just placed the blocks in position and then backfilled the minimal area that was left with sand. The InsulFoam® GF made installation easier and more efficient.”

Installation of a drainage mat was also necessary in order to ensure that any water that might collect around the abutment would drain properly and decrease the potential for any damage that might be caused by moisture penetration. By ensuring that water drained away from the abutment, the drainage mat would also eliminate the horizontal pressure that standing water would create.

The entire construction project was completed by September 2008, a short 6 months after it was started, and the bridge was re-opened to traffic. The use of geofoam in this project not only offered enhanced labor and cost savings, but also provided the increased, long-term stability and superior performance needed for the ever-moving technological hub of Omaha, Nebraska.

 Full article (pdf)



Nico Sutmoller, Insulfoam Geofoam Specialist

Nico Sutmoller, Insulfoam Geofoam Specialist

Contact Nico Sutmoller, Geofoam Specialist

Ask Nico to Connect on LinkedIn | Follow Insulfoam on LinkedIn


Local Governments use Geofoam to Overcome Common Geotechnical Challenges

US50 near Montrose, CO

Over 100 times lighter than soil, EPS Geofoam continues to prove to be successful in high-volume fill and soil stabilization projects such as roads, bridges, levees and buildings.  Local city and county agencies have used Insulfoam Geofoam in many projects to simplify construction and reduce costs for public works projects.  Geofoam has many features and benefits to help overcome common geotechnical challenges:  high load-bearing capacities, does not decompose, decay, or produce undesirable gases or leachates, fully recyclable, durable and does not require maintenance under normal conditions throughout service life, unaffected by freeze-thaw cycles, moisture, and road salts.

Read more on how the following Geofoam applications were used from project to project in Government Engineering Journal’s article, Geofoam:  A Primer.

Slope Stabilization:

  • US50 near Montrose, CO
  • Highway 12 near White Pass in WA State
  • US101 in Northern CA

Lightweight Void Fill:

  • Fairfeld-Suisun Water Treatment Plant channel walls in Solano County, CA
  • Idaho Transportation Department

Lateral load reduction on Retaining Structures:

  • Pacific Street Bridge Widening in Omaha NE

Soft Soil Remediation:

  • Alaskan Way Viaduct replacement in Seattle, WA
  • I-80/I-65 interchange widening in Gary, IN
  • North Creek Levee raising in Bothell, WA