We Are ICF (Insulated Concrete Form)
Professional Installers

Cornerstone truly believes that ICF construction is one of your best options when it comes to the structure of your home, business or addition.

ICFs for Residential

Read our answers to frequently asked questions about ICFs from inquisitive people like you. 

ICFs for Commercial Builders

Explore why more builders are looking to ICFs as their choice for building commercially. 

ICFs for Architects and Engineers

Cornerstone is an industry-leading expert in ICF installation and building techniques. Let us share our knowledge with you! 

Why Design with ICFs


Insulated Concrete Forms (ICFs) are hollow foam blocks made of EPS (Expanded Polystyrene), that are designed to interlock and stack to form the shape of the exterior walls of a building or home. They are reinforced with steel rebar and then filled with concrete. 

ICFs combine EPS, one of the finest insulating materials, with one of the strongest, structural building materials—steel reinforced concrete. The result is a wall system of unmatched energy efficiency, strength, noise reduction, and ultimate comfort.

ICF construction greatly reduces energy costs and is ideal for residential, commercial and remodeling applications. Cornerstone Custom Construction provides professional installation expertise in this specialized field.


  • Energy-Efficient Superior Soundproofing
  • Safety and Security
  • Built-in Vapor & Air Barriers
  • 8x Stronger Than Wood Framing
  • High Indoor Air Quality


“We made the switch to ICFs from block and have been very satisfied. Cornerstone is the local expert on ICFs and delivers a quality product on a timely basis at a price which is competitive with block”  

—Kurt Erickson, Quality Home Transformations, Inc.

"I highly recommend Cornerstone Custom Construction, Inc. as your ICF and flatwork sub, particularly if you are a first-time ICFs builder. The guidance and attention to detail given by Kelly and his crew will bring trouble-free success to your ICFs projects and their efficiency will be good for your bottom line."

—Donald S. Kotoski - Providence Homes, Inc.

“Cornerstone Custom Construction is without a question truly committed to high-quality ICFs and building technology.”  

—Ted Capistrant, The Profit Builder’s Network

ICF Insulated Concrete Forms Overview by Fox Blocks ICF

Frequently Asked Questions About ICFs From Homeowners

Why should I build my home using ICFs?

ICFs create homes and buildings that are more energy efficient, stronger, more sound resistant, and more environmentally sustainable than any other construction method.

Exactly how do homeowners benefit from using ICFs?

Comfort. Houses built with ICF walls have a much more even temperature throughout the day and night. They have virtually no "cold spots," and far fewer drafts.

Durability. The rigidity of concrete construction reduces the flex in floors and cuts shifting and vibration from the force of the wind or the slamming of a door. Concrete houses survive high-force winds like hurricanes far better than wood homes. When properly reinforced, they should also withstand earthquakes well.

Quiet. About one-sixth as much sound gets through an ICF wall as compared to an ordinary frame wall. This sharply cuts the intrusion of noise from outside.

Energy efficiency. The superior insulation, air tightness, and mass of ICF walls cuts the amount of energy needed for heating and cooling by 30-40%. This can save $200-300 per year in a typical home. In addition, it allows the installation of smaller heating and cooling equipment, which can reduce the initial cost of a house by over a thousand dollars.

Design flexibility. ICF houses can be completed with almost any interior and exterior finishes, and can take any shape as easily as wood-frame homes. In fact, some interesting effects, such as curved walls and frequent corners, can be less expensive to build into an ICF home.

Isn't it hard to remodel an ICF home?

Not at all. Most remodeling contractors have the ability to cut openings into an ICF wall. Most tool rental stores rent out concrete cutting saws for cutting openings.

Where have ICF homes been built?

ICF homes have been built all across North America, in every region, and virtually every state and province. ICF homes are prized in the Northeast, Upper Midwest and Canada for their energy efficiency and comfortable indoor climate. Along the hurricane-plagued Eastern Seaboard and Gulf Coast, ICF homes are similarly valued for their durability and resistance to storms. In the Southwest, ICF homes keep their occupants much cooler in the summer and warmer in the winter. On the West Coast, ICF homes provide safety from earthquakes and fires. In the provinces of Canada, the growth rate of ICF homes has exceeded even that of the United States. Spurred by government programs to encourage the construction of energy-efficient housing, more Canadian builders already know what their U.S. counterparts are just now discovering: It is often less expensive to build with ICFs from footing to eaves than it is to build a stick-frame house to the same insulation standard.

How energy-efficient are ICFs for my home?

Based on research performed by Building Works Inc., houses built with ICF exterior walls require an estimated 44% less energy to heat and 32% less energy to cool than comparable wood-frame houses. A typical 2000 square foot home in the center of the U.S. will save approximately $200 in heating costs each year and $65 in air conditioning each year. The bigger the house, the bigger the savings. In colder areas of the U.S., heating savings will be more and cooling savings less. In hotter areas, heating savings will be less and cooling savings more. Such energy-efficient performance comes in large part from the polystyrene foam on the interior and exterior of ICF walls, which range from R-17 to R-26, compared to wood frame's R-9 to R-15 walls. Also, ICF walls are tighter, reducing infiltration (air leakage) by 50% over wood-frame homes.

Are ICF buildings safer than wood-framed buildings?

Yes. ICF buildings are up to 8.5 times stronger than wood-framed buildings. As a result, ICF walls are more able to withstand severe weather such as hurricanes and tornadoes. Most ICF walls have a 2-hour fire rating, as opposed to 15 minutes for a comparable wood-framed wall.

What about rot and mold issues?

Over the past 20 years, builders have been asked to build tighter wood homes using house wraps, seals, caulk, tapes, and gaskets in order to reduce the amount of air infiltration/loss in the home. When these products fail, moisture gets trapped inside the open cavity of a wood stud wall, causing mold and mildew problems and rot. The foam used in ICF (Expanded Polystyrene)is a closed-cell structure making absorption and/or migration of moisture virtually impossible. ICFs are closed-cavity construction, with the concrete filling the entire cavity of the wall. Given that there is no place for moisture to travel in the wall, and that foam, steel reinforcing bar and concrete are all three inorganic material, ICFs are resistant to mold and mildew problems.

How much do ICF walls cost?

Because of low labor requirements, total construction cost is only slightly above the cost of wood-frame, despite the use of high-quality materials. When built by crews experienced with ICF construction, completed ICF homes cost about 0.5 to 4% more than they would if they had been built of frame.

Putting the numbers differently, building a house of ICFs adds approximately $0.25-3.25 per square foot to the total cost. Simply building the walls adds about $1.00-4.00. But one can then subtract as much as $.75 in savings from smaller heating and cooling equipment.

How can I build my next project using concrete and ICFs?

Call Cornerstone Custom Construction, Inc. at 763-754-3939 or email us through our Contact Us page. Cornerstone has the experience and knowledge to do the job right. Ask all the questions and see for yourself how ICF construction provides a superior house for a modest price.


ICF Benefits For Commercial Builders

ICF Information For Architects and Designers

Building with ICFs makes you more profitable:

Faster construction times. ICF walls go up quickly and easily. You may find that you can build faster with ICFs than you can with traditional methods with four steps in one construction. Shorter construction time means you can complete more projects than ever before. Although it looks new and different, ICF-built homes require less total labor than a wood-framed home. And ICFs are very lightweight, so crews stay fresh through the day. Likewise, ICFs present no problem for the sub-contractors who come after the walls are poured. Since holes, chases, and rectangles are easily cut into ICFs with a knife or saw, installation of mechanical systems is a snap. The fastening of drywall and lap siding is just as fast and easy. And mid-course corrections, such as moving an opening, are no big deal—just saw it out and reform. It's not more difficult to make changes to an ICF wall—it's just different.

No shortage of materials. Build with ICFs and you won't have to deal with lumber prices as they fluctuate, while supply dwindle. ICFs are also great for clients who want to build "green."

Market expansion. More and more consumers want to build with ICFs, and you can be the one they're turning to. Plus, when you are able to offer an alternative to wood-framed walls, you're showing that you are innovative in your building techniques.

Tax credits. The Internal Revenue Service (IRS) provides tax credits for home builders constructing energy efficient homes under the Energy Policy Act of 2005.

Versatile System - Flexible Designs. ICF homes can be designed in any style and will accept any traditional exterior finish including vinyl or wood siding, stucco, and brick. Because custom angles and curves are easily created, it's simple to build in bows, bays, and radiuses. And ICF systems accommodate any of today's most popular design features, such as tall walls, large openings, long floor spans, and cathedral ceilings.

Internationally Proven & Code-Accepted. Originally developed in Europe (where concrete homebuilding is standard), ICF systems have been used successfully around the world for more than 30 years. Thousands of ICF homes have been built in recent years throughout the United States and Canada. They have proven successful in every region and climate, from Orlando to Calgary. ICF systems are accepted by all the major model codes in the U.S., and by the R-2000 program in Canada.

Cost Competitive. Over the last ten years, concrete prices have been remarkably stable. Recent price increases in other materials have generated interest in concrete building systems as never before. Labor savings and readily available materials make ICFs, feature for feature, one of the most cost competitive wall systems in the U.S. and Canadian housing markets.

Performance You Can Live With:

ICFs offer several benefits to homeowners, including greater comfort and lower energy bills—ICFs start with high thermal performance. An ICF wall with four inches of Type II ASTM C578 polystyrene foam insulation, combined with a five-inch concrete wall, is rated above R-17 at 75-degree mean test temperatures. Air barriers provided by the EPS insulation and concrete eliminate convection currents and the high thermal mass of the concrete walls buffers the home's interior from extreme outdoor temperatures. The result is a 25 to 50 percent energy savings over traditional stud-wall or steel-frame homes.

Super Quiet. In sound transmission tests, ICF walls allowed less than one-third as much sound to travel through them than did ordinary frame walls insulated with fiberglass.

Super Durable. Due to the superior strength of concrete, ICF homes are able to survive hurricane and tornado winds. ICF homes are becoming very popular in southern and midwestern states, where hurricanes and tornados are more likely to strike.

Ease of Construction. ICF homes require fewer man-hours than stud-wall construction. Once a construction crew is trained in the ICF installation process, homes can be completed much more quickly than stud and fiberglass wall constructions.

Design Flexibility. ICFs also allow for greater design flexibility. ICF forms can accommodate tall walls, curved walls, large openings, long ceiling spans, custom angles and cathedral ceilings. Because foam is easy to cut and shape, it allows contractors to build curved walls and custom angles without worrying about structural load considerations. To achieve these designs with stud-wall construction requires a lot more cutting and finishing work.

Environmentally Responsible. Building with ICF homes can provide environmental benefits in a number of ways. ICF's minimize the use of lumber, which preserves trees. Homes built using stud-wall construction typically result in a lot of cutting and trimming and, consequently, waste costly for the contractor. Finally, the superior thermal performance provided by ICF homes significantly lower the energy requirements for heating and cooling which saves the homeowner money.

Future Market Trends

Acceptance of ICF homes is growing rapidly, from a humble start after the Energy Crisis in the 1970s. Nearly 200 ICF homes were constructed in 1993. By 1997, the number had grown to approximately 8,000 per year. By 2000, ten times that much.

Great efforts from the Portland Cement Association (PCA) are being made to educate builders and homeowners about concrete walls systems as a great option to home building. According to a recent PCA survey, the awareness of ICFs and number of homes built using above-grade concrete walls had an impressive 350% increase between 1993 and 1999.


If you're not building with insulated concrete forms (ICFs) yet for your residential and commercial projects, chances are, you soon will be. Join the hundreds of builders across the country who have discovered a better way to build - with insulating concrete forms.
When you choose ICF, you are building with a concrete form system that is easier to use than any other while providing your customers with superior structures. ICFs accomplish four steps in one - steel-reinforced concrete walls, insulation, vapor barrier, and furring - saving time and money. Plus, ICF walls are stronger than wood-framed walls, concrete block, tilt-up and anything else in the industry.

And if they haven't already, your prospective customers will start asking you about building with ICFs very soon. Fortunately, you're in the right place with Cornerstone Custom Construction, Inc. because we build with ICFs quickly and easily. Cornerstone also gives you support before, during and after you start working with us.

Further Reading

DSIRE: Database of State Incentives for Renewables & Efficiency
Concrete Thinking for a Sustainable World: "ICFs - Flexible, integrated wall construction"
Amvic, "Why Build with ICFs?"


Our goal for Commercial ICF Construction is to contact, present and nurture qualified architectural firms and development companies, educating and growing the awareness of how working with Cornerstone and ICFs can provide excellent full circle building solutions.

ICF Technology—The Cutting Edge in Commercial Building Wall Systems

For nearly half a century, leave-in-place Insulating Concrete Forms have proven themselves as a premier, high-performance wall system, offering superior economic, environmental, and durability benefits.

Today, as more and more commercial building owners, architects, contractors, lenders and investors discover the cutting-edge value of ICFs, a 30+% annual growth makes it the most rapidly expanding building system in the U.S. ICFs use rigid foam insulation to form and encase concrete walls, like a concrete sandwich with insulating foam in place of the bread. On the job site, interlocking ICF blocks or panels are assembled with remarkable ease and held in place at the desired thickness with engineered ties. Reinforcing is often added, then concrete is poured into the cavity. Along with systems for easy mounting of finishes and channeling of utilities, the insulation remains in place with the concrete to provide ICFs' advanced economic, thermal, safety, environmental and comfort benefits.

The Inside Story on ICFs

Lightweight polystyrene foam forms assemble easily and remain as insulation. The integral form ties allow attachment of any interior wallboard while wiring paths are easily cut into the foam. A reinforced poured concrete core provides superior strength and durability.

Apply any exterior finish, from brick to acrylic finishes and more.

The quality of concrete costs little more.
The many benefits of a concrete building made with insulating concrete forms (ICFs) are available for only slightly more than the cost of ordinary wood frame. ICFs are simple to assemble and they consolidate several construction steps into one. The walls can be economical despite the use of high-quality materials.

How much does an ICF building cost?

Buildings by experienced contractors cost about 0.5-4% more than wood frame structures of the same design. Typical new U.S. buildings cost $60-100 per square foot. Building walls of ICFs adds $1.00-$4.00 to this figure. But since ICF buildings are more energy-efficient, the heating and cooling equipment can be smaller than in a frame structure. This can cut the cost of the final building by an estimated $.75 per square foot. So the net extra cost is about $.25-$3.25.

Concrete buildings save energy.

Building a concrete structure with insulating concrete forms (ICFs) saves energy and money. The greater insulation, tighter construction, and temperature-smoothing mass of the walls conserve heating and cooling energy much better than conventional wood-frame walls. This reduces monthly fuel bills. It also allows the use of smaller heating and cooling equipment, saving money in construction.

How much will I save?

Buildings constructed with ICF exterior walls require an estimated 44% less energy to heat and 32% less energy to cool than comparable frame structures. A typical 2000 square foot building in the center of the U.S. will save approximately $200 in heating costs and $65 in air conditioning each year.

The bigger the building, the bigger the savings. In colder areas of the U.S. and Canada, heating savings will be more and cooling savings less. In hotter areas, heating savings will be less and cooling savings more.

How do we know all this?

The energy savings estimates come from a study of single-family houses spread across the U.S. and Canada. Researchers gathered data on 58 houses in all. Half had exterior walls constructed of concrete using ICFs made of expanded polystyrene (EPS) or extruded polystyrene (XPS) foam. The other half were neighboring houses with walls constructed of wood frame. All houses were relatively new (less than 6 years old) and built with modern methods.

The researchers compared the energy bill of each concrete house to its frame counterpart, carefully correcting for important differences to get an "apples-to-apples" comparison. Estimates of equipment savings are actual numbers reported by contractors that build ICF houses.

Where do the savings come from?

Insulating values for ICF walls using polystyrene foam are R-17 to R-26, compared to wood frame's R-9 to R-15. So ICF walls are expected to cut the conduction losses through foundation and above-grade walls by about half. And ICF walls are tighter. In tests, ICF houses averaged about 1/2 as much infiltration (air leakage) as frame homes. ICF walls do more than cut down on the biggest types of energy loss. The concrete gives them the heat-absorbing property, "thermal mass". This is the ability to smooth out large swings in temperature. It keeps the walls of the building warmer when the outdoor temperature hits its coldest extreme, and keeps them cooler when the outdoor temperature is hottest. The walls themselves "add back" heat or cooling to the building when it needs them most. This contributes about 6% of the structure's required energy for free.

Reduced equipment costs result from the energy savings. Since the energy needed is less, the furnaces and compressors that heat and cool can be smaller. And the more the energy savings, the greater the possible reduction in equipment size-- and the equipment cost.

What's the bottom line?

In planning a building, you can estimate that choosing concrete walls made of ICFs will save you hundreds of dollars per year in energy costs. As shown in the graphs, the savings are greater the bigger the building is. Heating savings are highest in cold climates, and cooling savings highest in warm climates.

Further Reading: