PROJECT PROFILE: Florida Pool Deck Uses Geofoam to Reduce Weight

Florida Pool Deck  |  Tallahassee, FL  |  View Project Profile (pdf)

Known primarily for its use as a soil stabilizer in transportation projects, EPS geofoam is being viewed by engineers and contractors as the material of choice for a multitude of other commercial and residential applications.

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Florida pool deck, geofoam installation

Contractors use geofoam to simplify construction of swimming pools in residential, commercial and institutional uses, including hotels, schools and community centers.  Project teams can order the blocks pre-but to precise dimensions or can easily cut them to size and shape on site.  This simplifies the concrete forming process, and greatly reduces weight for construction of rooftop pools or sites with poor load-bearing soils.  Once crews form the pool basin and decks with geofoam, they can apply shotcrete directly to the foam.

In this Florida project, geofoam was used to lighten up the load over the upper elevations building given the pool is on the 2nd floor of this five-store building.  Pool decks are installed on both the East and West buildings on the campus.

Given its low weight, EPS geofoam is well suited as a structural void fill in concrete forming operations.  Crews can easily fabricate virtually any shape or sloe, and the material eliminates separate concrete pours for vertical wall sections and topping slabs.  Applications include bridge column formwork, stadium seating in auditoriums and sports arenas, stairways, podiums, loading docks, and rooftop pool decks.  EPS geofoam can be manufactured into custom-cut blocks in various shapes and sizes to enable contractors to quickly build up these and similar features.

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation




A Park with Soil?

Originally published in Site Prep Magazine, September 2014 (digital edition) (pdf)

Lightweight geofoam enables earthworks for new park located atop Chicago parking garage.

Throughout the summer, Chicago residents and visitors saw what looked like acres of piled snow at a construction site bordering Lake Michigan, despite the city’s typical sweltering June and July temperatures..

The “snow” was actually large, white blocks of expanded polystyrene (EPS) geofoam that contractors were installing to form berms and landscaped contours for the new Maggie Daley Park.

Site Prep Challenges

The Chicago Park District decided to develop a 28-acre site adjacent to the city’s renowned Millennium and Grant parks as a “world-class public landscape at a keystone location” to meet the “evolving open space needs of downtown Chicago.”  The Maggie Daley Park, scheduled for final planting in spring 2015, occupies the former Daley Bicentennial Plaza.  The site was a rail yard and surface parking lot for cars until the early 1950s, at which time the city moved the parking spaces underground.

The "snow" on Chicago's famed waterfront in the heat of summer is actually EPS geofoam, being used to construct Maggie Daley Park atop a parking garage that cannot hold heavy soil.

The “snow” on Chicago’s famed waterfront in the heat of summer is actually EPS geofoam, being used to construct Maggie Daley Park atop a parking garage that cannot hold heavy soil.

Therin lies one of the key site preparation challenges for Maggie Daley Park, which will be located on top of the 3,700-car East Monroe Street

Being built at the foot of Chicago, Maggie Daley Park is being constructed using EPS geofoam that will allow the parking garage below to remain in place.

Being built at the foot of Chicago, Maggie Daley Park is being constructed using EPS geofoam that will allow the parking garage below to remain in place.

Parking Garage.  The park’s landscape architects, Michael Van Valkenburgh Associates of Brooklyn, N.Y., envisioned extensive earthworks, which they described as “curvilinear, topographically dramatic and relentlessly heterogeneous.”  Contractors typically would use soil to form such landscape contours, but that was not feasible for this project because the upper slabs of the sprawling, decades-old parking garage were not designed to accommodate that much weight.

Instead, crews with Chicago-based Walsh Construction used EPS geofoam as an ultra-lightweight yet durable fill to form the park’s hills and valleys.  Geofoam is approximately 100 times lighter than soil (0.7-2.85 lbs./cu.ft. for geofoam compared to 110-120 lbs./cu.ft. for soil), so it enabled the Maggie Daley Park designers to create a visually interesting landscape and still keep the garage in place.  Walsh installed 65,000 cu. yes. of geofoam, along with some geofoam that had been previously installed in Daley Bicentennial Plaza.

“It allows you the freedom to be creative,” landscape architect Peter Schaudt, whose company Hoerr Schaudt Landscape Architects has used goefoam in other Chicago projects, commented in a recent Chicago Sun-Times article.

What Makes Geofoam Special?

Despite its low weight, EPS geofoam is strong enough to support heavy loads, such as those imposed by jet aircraft and locomotives, as demonstrated by its successful use as a sub grade for runways, taxiways and rail beds.  Following are the material’s key physical characteristics.

Weight:  In addition to weighing far less than soil, EPS geofoam is much lighter than other lightweight fills, as per the chart below.

site prep_maggie daley3Compressive Resistance:  EPS geofoam is engineered for high strength with compressive resistance values of 317-2,678 lbs./sq.ft. at a 1-percent strain.  The material’s Westergaard modulus of sub grade reaction “k” values indicate that EPS geofoam has better bearing capacity than most foundation soils.  As long as combined dead/live loads do not exceed 1-percent strain, the material will not creep or experience plastic yield.

Buoyancy:  Although this is not an issue in most applications because EPS geofoam is buoyant, it is important to consider uplift forces in applications where the material will be partially or fully submerged.  Buoyancy can be minimized by installing geofoam above the water table and ensuring suitable drainage.  Additionally, the surcharge from overlying soils or pavements is frequently sufficient to offset uplift forces.  Where high water exposure cannot be avoided, supplemental restraints like restraining straps might be required.  The fact that the material’s buoyancy can be readily addressed is seen in its successful use in several levees in the U.S.

Damaging Elements:  EPS geofoam does not decompose, nor is it affected by freeze-thaw cycles or road salts, and is considered  permanent in civil engineering applications.  Petroleum products and other chemicals can damage EPS, so geofoam designs should include a compatible geomembrane or a continuous load distribution slab to protect the material from fuel spills or exposure to hydrocarbons in contaminated soils in applications where these conditions might exist.  EPS is combustible, so it is important to check with the particular manufacturer if the geofoam includes a flame retardant.  Flammability is typically only a concern if open flames are present during installation, as geofoam is usually isolated by membranes, soils or pavement in the finished application.

Working With Geofoam

EPS geofoam greatly simplifies site prep, because it does not require the surcharging, preloading or staging often necessary with other fills.  The material is also easy for crews to place by hand or with small mechanical equipment.  A reputable geofoam manufacturer will provide contractors with detailed information on working with the material, and producers like Insulfoam will provide on-site consultations.

…geofoam is lightweight, durable, easy to use and more consistent that other fills…

Geofoam installation does not require much training.  Among the installation factors to keep in mind:

  • Sizing:  Standard-size blocks are 4 ft. by 8 ft., at various thicknesses.  A well-equipped manufacturer can produce custom sizes and shapes to meet any project need, or crews can easily trim geofoam on the job site using a hot wire cutter (which some manufacturers will supply) or with handsaws or chainsaws.
  • Block Placement:  Typical geofoam designs call for installing the blocks on a level course of sand, pea gravel or any locally available permeable leveling course material.  Similar  to how brick walls are configured, geofoam blocks usually are staggered so their joints are offset and not located in the same vertical plane.  Depending on the engineering requirements, the blocks can be interconnected with either barbed plates or polyurethane adhesive.
  • Wind Protection:  Geofoam is lightweight, so it is important contractors weigh or tie down stockpiles on windy job sites.

A Wide Range of Applications

Crews with Walsh Construction use EPS geofoam as an ultra-lightweight yet durable fill to form the hills and valleys that will comprise Maggie Daley Park on Chicago's waterfront.

Crews with Walsh Construction use EPS geofoam as an ultra-lightweight yet durable fill to form the hills and valleys that will comprise Maggie Daley Park on Chicago’s waterfront.

Because geofoam is lightweight, durable, easy to use and more consistent than other fills, it is being used by building professionals as a fill alternative in numerous large civil projects, as well as in residential and commercial buildings.  Among example installations:

  • I-80 / I-65 Interchange, Gary, Ind,:  To reduce excavation volumes of high-organic content soils at the south end of Lake Michigan, Walsh Construction instead used EPS geofoam for the road sub grade.  “There’s no comparison to using traditional fill,” says Walsh Construction site supervisor Gary Walsh.  “There are no lifts needed; we just unloaded the blocks and it installed fast.”
  • Alaskan Way Viaduct, Seattle, Wash.:  The Seattle waterfront has notoriously soft soils, since much of the downtown area was built on fills created by re-grading the city in its early days.  As part of embankment construction for the Alaskan Way Viaduct replacement, project engineers had to ensure that new ramps would not induce settlements on the underlying soft soils, which could impact the stability of adjacent elevated structures.  EPS geofoam provided the necessary load support at a low weight and eliminated the need to surcharge the soil.
  • CRH-UBH Freeway Interchange, Valsayn, Trinidad:  As discussed in an earlier Site Prep article (“Standing on Solid Ground,” March, 2014), contractors used geofoam as a lightweight embankment fill on top of the pile cap for an existing flyover ramp pier, to avoid any modifications of the pier’s seismic behavior in the earthquake prone region.

Beyond such road applications, geofoam is an ideal lightweight void fill on vegetated roofs, which is a similar application to the landscape contouring of Maggie Daley Park on top of the East Monroe Street Parking Garage in the heart of Chicago.

Maggie Daley Park to Turn Garage into Rolling Hills- ABC Chicago News

More news coverage on the use of InsulFoam Geofoam in Chicago’s newest and biggest downtown attractions, Maggie Daley Park. When complete, the new park will have a distinctive presence with signature elements like rock-climbing sculptures, an ice-skating ribbon, and play garden.  Read more in the latest and on-going news coverage on details and view the project’s job site camera:

– Geofoam Helps Mold the Construction of Chicago’s New Downtown Maggie Daley Park.

  Foam Blocks Form Hilly Landscape at Maggie Daley Park Site, Chicago Sun-Times

Originally aired and published on  ABC 7 Chicago News, by Paul Meincke

chicago abc_maggie daleyBuilding a park on top of a parking garage is an engineering question whose answer rests with the new Maggie Daley Park on Chicago’s lakefront.

In the shadow of towers made of concrete and steel, there are building blocks of a different sort. Thousands of them are being layered together to give shape to what will be Maggie Daley Park.

“We’re going to transform what was a flat, sort of uninviting area into a gem for Chicago that compliments Millenium Park,” said Chicago Park District CEO Michael Kelly.

That transformation has a lot to do with topography. When this 20-acre park is done, its northeast corner will sit 30 feet higher than the southwest. That’s a lot of dirt. And dirt weighs a lot. And a lot of weight would not be welcome atop the two story parking garage that sits directly underneath. So, what do you use? Geofoam.

“Geofoam is essentially Styrofoam. It’s lightweight fill,” Kelly said

It’s 100 times lighter than soil. Geofoam isn’t a new concept. It was used here before, but there’s a lot more of it now, 75,000 cubic yards of it will be sculpted and tacked down to create a rolling terrain.

On top of the geofoam goes the dirt which will be deep enough in spots to accommodate the roots of one-thousand new trees. If you’d never seen the geofoam going in, you’d never know it was there.

“That’s essentially the best compliment we could get once this park is open and that is that people don’t realize that it’s a park constructed on top of a garage,” said project engineer Nichole Sheehan. “It’s a park that people are going to love and hopefully come to all the time.”

The park district has been recording its birth with time lapse camera, from barren garage roof to the building of baby hills, and when the park’s soft opening comes next fall, this is the vision. Three of the 20 acres devoted to a children’s playground. Just up the path, a 25 foot climbing wall, and when the cold months come, a feed of built in refrigerant will convert that path into a 400 meter ice skating ribbon – attracting old Hans Brinkers or perhaps young Blackhawks.

From debris dating back to the great Chicago fire to geofoam, this piece of Chicago has undergone remarkable change over the years.

In the late 40’s and early 50’s, there were lots of railroad, lots of parking that over the years goes went away or went underground.

“Somewhere way down there, there’s fill,” Kelly said. “There’s probably some old railroad scrap. Now we’re standing on geofoam and we’re building a green park. We’re building a 20 acre green roof is essentially what we’re doing with a thousand trees.”

The first of the trees come soon. The grand opening of Maggie Daley Park comes next Spring. Its birthing thus far carries four words welcomed in urban re-design.

Maggie Daley Park carries a roughly $55 million price tag. Most of that comes from parking garage lease money and private contributions along with five million in park district capital funds.


Foam blocks form hilly landscape at Maggie Daley Park Site, Chicago Sun-Times

Great story in the Chicago Sun-Times about the use of InsulFoam Geofoam in Chicago’s newest and biggest downtown attractions, Maggie Daley Park.  This is a very large geofoam project, the new park will have a distinctive presence with signature elements like rock-climbing sculptures, an ice-skating ribbon, and play garden.  Read more details and view the project’s job site camera:  Geofoam Helps Mold the Construction of Chicago’s New Downtown Maggie Daley Park.

Originally published on Chicago Sun-Times,, by Tina SFondeles


Maggie Daley Park is being formed using GeoFoam, a plastic foam substance that has been used once the ’80’s to create landscape and hills on others flat land.  – Brian Jackson  |  Sun-Times

Chicago’s shoveling days should be over, but the future Maggie Daley Park kind of looks like a winter wonderland, full of white building blocks.

Those giant blocks of Geofoam will transform flat land into a hilly landscape at the park site, which spans 20 acres and is bordered on the west by Columbus, the north by Randolph, the south by Monroe and the east by Lake Shore Drive.

Landscape architects say the lightweight, cost-effective, environmentally safe and recyclable fill material is key to creativity. The expanded polystyrene is being used around the world and locally to contour flat Midwestern land.

At Maggie Daley Park, crews are using old Geofoam — already part of Daley Bicentennial Plaza — and a lot of new blocks to shape the park. From various vantage points around the park, onlookers can watch as the foam is delivered every day — six truckloads — and crews have already filled the northeast and northwest corners of the park, and are moving south.

The foam installation will be done by early summer. By September, dirt will be placed over the foam. It’s even being used for the park’s ice skating ribbon.

“For the ice ribbon, you’ve got up and down. It’s not just flat,” said Lowell Zarzueta, of Walsh Construction, who is overseeing part of the second phase of the project. “For you to go up high, you almost have to skate super fast, just to get over that little hump.”

He said the foam is being used to create a hill that will be even with Randolph Street, making it easy for people to come into the park. There are also peaks at the northeast corner, where a picnic area is being built.

“With Maggie Daley Park, you’re going to have hills. The park will offer these beautiful vistas of Lake Michigan, which it never had there,” said Bob O’Neill, president of the Grant Park Conservancy. “In order to do that, to get these hills, and these rolling meadows over a whole flat area in Chicago, to get any topography, especially on top of a structure, you need Geofoam.”

Crews on Friday said deliveries of Geofoam are about half done. The mass quantity of snow Chicago received this year did slow work a bit, but crews said phase two of the park — earthwork, utilities, paving, architectural and program elements, soil placement and planting — is on schedule for completion in October.

Here’s how crews are layering the park: First it was excavated, the dirt placed in nearby Peanut Park to be reused. Tar was put over the garage, then a layer of black tarp. It’s then tested to make sure it’s waterproofed to prevent leaks to the garage below. Four inches of stone are placed on top, and then the foam is placed with yet another black tarp over it. Dirt will go over the foam.

Come next spring, the ground will become green again, as landscaping and planting will be in full swing.

This isn’t the first time the product has been used in Chicago. It was also used for the Daley Plaza renovation — where the trees are now planted, and for the Soldier Field remodeling, where Geofoam was placed as fill over the garage, creating a hilly and grassy landscape near Soldier Field and the Field Museum.

Peter Schaudt, the landscape architect behind both renovations, said Geofoam played a major role in the projects.

“I think it allows you the freedom to be creative,” said Schaudt, of Hoerr Schaudt Landscape Architects. “It allows you to really model the land in an artificial way, and the great thing is when you put the soil and lawn and trees on top of it, it’s an illusion.”

The product also is very strong, he said. “It never dematerializes. It stays the same size. At Soldier Field, it was used to support 18,000 pounds.

“It’s much more substantial than just putting a thin veneer over a roof, and it allows you to create a lot of great and dramatic changes,” Schaudt said.

A soft opening for the $55 million park, named for the late wife of former Mayor Richard M. Daley, is scheduled for fall, and the park will be officially completed by spring 2015. A park district website, features two webcams to view the construction.

Email:  |  Twitter: @TinaSfon

Geofoam Helps Mold the Construction of Chicago’s New Downtown Maggie Daley Park


Maggie Daley Job Site Cam, Dec 7th

Maggie Daley Job Site Cam, Dec 7th

With construction well underway the former Daley Bicentennial Plaza (next to Millennium Park) is on its way to being one of the “greenest” parks in America. The park is atop the large East Monroe Street Parking Garage, which has been restructured extensively including a new membrade above the garage which will also serve as the foundation that the park will sit on top of.

The new park, offers sweeping views of Lake Michigan, and combined with Millenium park “Peanut Park” will offer 45-50 acres of green roof over a downtown city parking garage.
So what does Insulfoam’s EPS Geofoam have to do with it? With about 60% of earthworks completes, crews have removed 82,000 cubic yards of existing fill (that existed beneath the soil for decades). Some of this is in fact lightweight fill material like Geofoam, and is still in excellent condition and is able to be recycled for reuse to create “hills” in the park. Geofoam will also support the base below new paths for bikers and walkers to get through to the lake paths.
Maggie Daley Park Rendering

Maggie Daley Park Rendering

The site itself now has the required EPS Geofoam blocks stock piled and ready for installation. In the days to come the installation of the acres of Geofoam will be seen on the bottom right hand side of THIS JOBSITE CAMERA.

Bob O’Neill, president of Grant Park Conservancy, in an article from the Chicago Sun Times called the park “more natural and much more informal” than Daley Bicentennial Park. And very kid-friendly, featuring a three-acre play garden, ice rink, climbing walls, a skating rink in the shape of a ribbon .“You’ll be able to walk up hills and see the lake,” O’Neill said. “When this is done . . . it’s going to be a much more green, sort of organic flow. Whereas Millennium Park is more structural and formal, this is more nature-oriented.”