Concrete Homes

rhinoblock.gifWhy Build a Concrete Home?

Concrete Homes built with Phoenix Insulated Concrete Forms (ICF's) are the most cost effective energy efficient form of construction available today. Concrete Homes have several distinct advantages over traditional wood frame construction:

To go to the Concrete Homes Gallery click on the following link: Concrete Homes Photo Gallery

Energy Efficiency

Concrete homes built with Phoenix ICF's are very Energy Efficient. Phoenix ICF walls have an "Effective" or "Equivalent" R-Value of 32. This means that a wood framed wall would have to be built to an R-32 to match the same R-value of an ICF wall.

Walls built with standard 2x6 construction with R-19 fiberglass insulation have an "Effective" R-Value of 13-16.

There are several properties that make ICF Walls twice as energy efficient as standard 2x6 construction. Reduced Air Infiltration, Continuous R-Value, and Thermal Mass of the concrete in the wall.

Reduced Air Infiltration

In a standard wood framed home, Air infiltration makes up approximately 30-40% of the heatloss for that home. Air can enter through the box sill, where the floor system is, between the floor sheeting & bottom plate, between the sill plate and foundation wall, where ever there is a crack between two pieces of wall sheeting, penetrations through the wall, and around windows & doors. The R-19 Fiberglass insulation installed in the majority of today's wood framed homes, is meant to work in an environment where there is NO air movement. When air is moving, it works its way right through the fiberglass, rendering the insulation almost useless. The more air infiltration, the worse the fiberglass insulation performs.

A Phoenix ICF wall has a solid core of concrete encapsulated on both sides by a continuous layer of EPS insulation. The wall is continuous from the footing to the eaves, with no breaks for floors or wall plates. Because of this, there is no way for air to enter any cracks in the wall. In a Concrete home, the floor system is normally kept to the inside of the wall, not allowing any air in the box sill. The only calculatable air infiltration that will occur is around the windows & doors.

Continuous R-Value

A standard 2x6 framed wall has an R-19 fiberglass insulation in each stud cavity. That means that everywhere there is a stud, there is no insulation. That also means that where the headers are above the doors and windows, there is also little or no insulation. When all of the studs, top & bottom plates and headers are added up, they account for approximately 20% of the wall's insulation. This is a big reason why the effective R-Value of an R-19 wall drops to R-16 or less.

A Phoenix ICF wall has 2 continuous layers of EPS on each side of a solid concrete wall. These continuous layers produce an actual R-Value of 20 with the insulation alone. Because the insulation is continuous, there are no "cold spots" as would be the case with a wood framed wall where each stud is. The R-value of the insulation by itself is R-20 throughout the entire wall from side to side, and top to bottom.

Thermal Mass

Thermal mass is more difficult to explain. A simple definition of thermal mass is the ability of a material or object to take on and store heat. A good common example of this is a blacktop parking lot on a hot summer day. The blacktop heats up, stores energy during the day, then as the sun goes down, and the air cools off, the blacktop is still warm , and slowly releases the heat until it is the same temperature as the night air.

The same is true for Concrete in an ICF wall. Because the concrete is insulated, it takes longer to heat up than a parking lot, and does not become as warm. The concrete does however store heat, then releases it as the air cools off. In the winter, the concrete pulls the 55 degree temperature up from the footings in the ground, and creates a buffer between the inside and outside of the house.

By having Thermal Mass, the temperature swings in a Concrete Home are minimized. What this means, is that in the summer, it takes longer for heat to get into the indoor living space. In the winter the buffer created between the inside and outside air temperatures reduces the amount of time the furnace has to run to account for the heat loss.

By reducing temperature swings, the heating & cooling equipment doesn't have run as much as in a wood framed home, therefore reducing the heating & cooling bills. This accounts for approximately 10% energy savings over wood framed construction in our area..

Disaster Resistant

Phoenix ICF Homes are Strong!

A steel reinforced concrete wall can withstand winds of up to 250 mph. An airborne missile study at Texas Tech University shows that concrete walls are also impervious to projectiles traveling over 100 mph, the speed they would be carried at in 200+ mph winds. Concrete does not burn, and homes built with Phoenix ICF have a 4 hour fire rating. In the unfortunate event that a tornado, hurricane, or fire were to hit an ICF home, you can feel secure knowing that you are living in the safest possible type of construction.

ICF homes have proven time & time again that they can withstand hurricanes, Tornados, fires and other disasters. The pictures & articles below show the strength of Concrete Homes

tornadohome.jpgConcrete Home Survives F3 Tornado

The ability of ICF homes to withstand hurricane- and tornado-force winds has long been known, but was made even more evident on August 18th, 2005 when a tornado destroyed most of the homes in a Stoughton, Wisconsin neighborhood. When the air cleared, one home was still standing with almost no damage: a concrete home, currently under construction, built with insulating concrete forms (ICFs).

Concrete Home Survives Hurricane Katrina

katrinahome.jpgThe Sundbergs' home, shown in the yellow circle, is a prime example of the durability of concrete homes.

The Sundbergs had been building their fully mitigated home for eight years, and it was 85% complete, when Hurricane Katrina slammed into their area on Aug. 29 with a huge storm surge and reported sustained winds of 125 mph. The water reached an elevation of 28 feet.

After the winds had died down and the water retreated to the Gulf of Mexico, the Sundbergs found that their home had survived the storm largely intact, with some blown-out windows, lost materials and missing upstairs panels. Now they are focusing their efforts on finishing the building before the next storm strikes

Concrete Home Survives California Wildfires

wildfirehome.jpgIn the summer & fall of 2003, Wildfires destroyed over 800,000 acres and over 3300 homes in Southern California. Insurance claims topped $12 billion. This was one of the most devastating natural disasters to hit California. The picture on the left shows one of the developments hit by the fire. The only home left standing was a Concrete home. If more homes had been built with Concrete the damage and cost could have been minimized.


Concrete Home Survives 90 mph Car Crashcarhome.jpg

Early on the morning of June 26, 2004, as Mr. Demczyk and his wife quietly slept inside their concrete home, tragedy was unfolding outside. At approximately 2:00AM an intoxicated driver was speeding down the Demczyk’s neighborhood street. According to police reports the driver of the Pontiac Firebird lost control of the vehicle, left the roadway and slammed into the exterior wall of the Demczyk’s residence at a speed of 90 miles per hour.

The concrete wall’s sound class rating of 48 offered the sleeping Demczyk’s no clue of the disaster. Stirred awake by a light thud, Mrs. Demczyk leisurely strolled through the house assuming a household object had fallen to the floor. To her surprise what she found was a set of headlights shining brightly through her living room window.

Proof of the concrete home's strength was evident once the clean up had been completed and the damage was accessed. There was only a 3’ x 5’ section of the wall’s exterior finish damaged by the crash. There was no damage to the concrete wall itself.

The 5800 SF, two-story, stucco home was constructed in Cape Coral, Florida in 1997 at a cost of $496,000. When asked if he was surprised by the strength of the wall, Demczyk responded “I can believe it. I have known that this house was solid since the day I built it. Strength, wind resistance, and insulation are the reasons I chose to go with ICF. Demczyk told us that emergency workers on the scene commented that the speeding vehicle would have penetrated the residence had the walls been concrete block or wood-frame.


The strength of a Phoenix ICF Concrete Home goes hand in hand with Disaster Resistance. Because an ICF wall is encapsulated in insulation, it actually produces up to 50% stronger concrete. A wall poured with 3000 psi concrete can test out at 4000 psi or higher.

A concrete wall is 20 times stronger than a wood framed wall. This is why Concrete Homes can withstand hurricanes, tornados, and even explosives.

A steel reinforced ICF wall is so strong, that the United States Military has been doing Blast testing on ICF wall sections with TNT. Read the article below.

ICFA/NVCAC Achieves Success During Blast Testing


The Insulating Concrete Form Association (ICFA) and the Northern Virginia Concrete Advisory Council successfully demonstrated the blast-resistant properties of ICF building systems during the Force Protection Equipment Demonstration (FPED V) April 26–28, 2005, at Quantico Marine Corps Base in Northern Virginia.

FPED was created in response to recent terrorism attacks and showcases commercial off-the-shelf (COTS) force protection equipment. During FPED V, over 500 vendors demonstrated 2,400 different products and services, such as surveillance systems, blast and ballistics mitigation products and chemical and biological troop protective gear. FPED is sponsor by the United States Department of Defense, United States Joint Chiefs of Staff, United States Department of Energy and United States National Institute of Justices.

During the blast demonstrations, eleven separate ICF reaction boxes, weighing 13 tons apiece and walls measuring 8 feet tall and 6 inches thick were subjected to explosion from 50 lbs of TNT at differing distances (3.5 feet to 10 feet) and to pressures from 300 pounds per square inch (PSI) to over 7,000 PSI.

Joseph Lyman, Executive Director of the ICFA, said, “FPED gives the ICF Industry the opportunity to showcase the impact-resistant properties of ICFs in real life. The results are amazing.”

Known for decades for its impact resistant properties, expanded polystyrene (EPS), the primary material in ICFs, has recently shown great potential as a blast-resistant product. In each instance during six different blast demonstrations, EPS compressed against the face of the concrete wall and reduced the pressure of the blast.

Based on the success experienced at FPED IV and V, the Portland Cement Association and ICFA are pursuing blast testing at a number of government funded blast ranges, which would allow for further acceptance of ICFs. Additionally, the Anti-Terrorism/Force Protection Standard, combined with the newest authorization from Congress to build military housing, provides the ICF community with a great opportunity to expand into a market well suited to ICF building systems.

“We look forward to participating in the AT/FP market and helping to provide safe and durable buildings,” says Lyman.

Mold, Rot & Pest Resistant

A Phoenix ICF home is made of Concrete & Polystyrene. Neither of these materials are an attractive food source for termites or carpenter ants. Because the exterior walls are concrete, mice or other rodents cannot chew through the wall, and nest inside your home.

Unlike wood frame construction, a Phoenix ICF home also has no wood in its exterior walls, which all but eliminates the opportunity for the development of rot or mold within the wall. Wood is an excellent source for mold growth when there is moisture and air present. Since Concrete & Polystyrene can't rot, a concrete home will far outlast wood framed construction.

Cleaner Indoor Living Environment

Phoenix ICF Home has much cleaner, healthier air to breathe than a wood framed home. Since the air infiltration is dramatically reduced, there is little or no chance for dust and pollens to enter the home. Not only does the cleaner air keep the home less dusty, but it is also a great benefit to people who have allergies. Concrete homes feature heat recovery air exchanging systems the provide highly filtered fresh air to the heating & cooling system. As the air exchange is controlled, utility costs are greatly reduced.


Concrete Homes built with Phoenix ICF's have a STC (Sound Transmission Class) of 55, which blocks out 90% of all air-borne noise. Sound Transmission Class rating is a single number quantifier used to rate walls, doors, and other partitions for their effectiveness in preventing sound transmission. Basically, a high STC rating indicates a more efficient sound absorption characteristic. That said, the typical wood frame wall has an STC (sound transmission class) rating of 33.

STC ratings, however, can be misleading because they are based on a logarithmic scale. An STC rating of 50 is not one better than 49. An STC rating of 50 should be deemed twice as effective as an STC rating of 49. Furthermore, the actual behavior of two partitions with the same STC rating can be dramatically different, as the STC is weighted in favor of the part of the sound spectrum that represents the human voice. In practice, one of the most annoying transmitted sounds between dwelling units tends to be the bass in music, a part of the sound spectrum far removed from the voice range. This in mind, an ICF wall with an STC rating of 50 will perform better than a wood frame wall with insulation and drywall, having an STC rating of 50. Same STC rating, but still the ICF wall is more effective in stopping the transmission of annoying sound. The chart below gives the general STC numbers and what they mean to people.

Because ICF Homes are so much quieter than wood framed homes, people living in them can enjoy the comforts of their home without being interrupted by unwanted outdoor noises such as traffic, barking dogs, loud music, or jets taking off at an airport.

STC-Lab Field STC Subjective description of effectiveness
26-30 20-22 Most sentences clearly understood
30-35 25-27 Many phrases and some sentences understood without straining to hear
35-40 30-32 Individual words and occasional phrases clearly heard and understood
42-45 35-37 Medium loud speech clearly audible, occasional words understood
47-50 40-42 Loud speech audible, music easily heard
52-55 45-47 Loud speech audible by straining to hear; music normally can be heard and may be disturbing
57-60 50-52 Loud speech essentially inaudible; music can be heard faintly but bass notes are disturbing
62-65 55 Music heard faintly, bass notes "thump"; power woodworking equipment clearly audible
70 60 Music still heard very faintly if played loud.
75+ 65+ Effectively blocks most air-borne noise sources.
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