A laid ICF foundation at a build site

Insulated Concrete Form (ICF) is becoming quite common in the home building industry. This innovative construction material is typically made of polystyrene foam blocks with gaps in between so you can pour a concrete wall.

You can use ICF for underground homes, basements, or entire multi-story houses. Moreover, you can start at the foundation and go all the way up to the roofline. 

This article will take a closer look at ICF foundations, including their advantages and disadvantages and their rough cost estimates. 

What Are ICF Foundations?

Insulated concrete form is used to lay a building foundation using intermeshing foam bricks. The hollow polystyrene walls construct the foundations outside the form, and fortifying rebar is placed inside for additional strength. After the forms are set, the concrete mixture is poured into the center.

ICF foundations are pretty unique as the forms integrate with the foundation.

a closeup of the inside of insulated concrete form blocks with rocks in the middle of it

Conventional concrete foundations use plywood forms to pour the foundations, which are later removed. On the other hand, polystyrene forms bind with the concrete, creating a permanent, built-in insulation layer. 

What Is the Cost of Building a Home with Insulated Concrete Forms?

You will have to pay around $280,000 to $430,000 for a 2,000-square foot insulated concrete form house. This figure roughly translates to $150-$160/square foot. So it is pretty similar to the cost of a concrete home. 

Unless you live in a warmer climate, builders use insulated concrete forms for all concrete home construction. However, certain builders use insulated concrete forms interchangeably with poured and removable forms.

You should speak to your builder to see which technique they suggest.

Nevertheless, the exact cost of building with ICF depends on many other factors, including:

  • Manufacturer – costs depend on which manufacturer you opt for and how far they are from your site location. The more distance they need to cover, the more you will have to pay. 
  • Concrete – what is the width of your ICF block, and what is the cost of concrete in your area?
  • ICF block – some ICF contractors tend to charge more if you opt for a particular ICF block that’s more challenging to work with. 
  • The complexity of the project – how accessible is your construction site? Do you have sufficient room to store a large number of ICF blocks?
  • Project engineer – who is going to engineer your project, and do they have experience with and knowledge of ICF blocks? The cost of a specific project can rise considerably because of extra rebar, and other unnecessary steps engineers might take due to a lack of familiarity.

What Is the Cost of ICF Foundations?

The installation of ICF foundations costs approximately $7/square foot. You can expect similar or the same prices for the cost to construct a wall. Since the forms stay fixed in place, ICF installation is less time-consuming and, as such, generally costs less as compared to poured concrete. 

How Much Money Can Insulated Concrete Form Save Over Time?

The payback and savings of an ICF home mainly depend on what you’re comparing it to. They even depend on how well your home is constructed.

If you have a very tight building envelope on your house, you’ll probably experience higher savings.

While you may have to pay five to ten percent more upfront for an ICF house, your energy bills will be less every month than if you were to construct a wood-frame house according to conventional standards. 

Industry leaders say that if you compare the initial cost of an ICF house to the utility savings over time, it costs the same as a wood-frame house. However, this again depends on various factors, such as your area’s climate. 

Advantages of ICF Foundations

ICF foundations offer several benefits, particularly in colder regions. They provide higher consistent, controlled insulation from moisture and cold and are more durable, robust, and energy-efficient than poured concrete foundations.

Here are some of the most significant benefits of using ICF foundations. 

1. More Strength 

An ICF foundation uses more rebar than conventional forming, which makes them much more robust. In addition, rebar makes the concrete more resistant to tension, reinforcing the structure’s overall strength. 

a close up of ICF blocks with rebar in the middle, showing the internal construction of the IFC foundation

Concrete is exceptionally resistant to compressive forces. However, it’s relatively weak when it comes to tensile force. This is where additional rebar turns out to be helpful.

It does not alter the concretes strength. However, it makes your home’s foundation sturdier as it can withstand several forces.

2. Increased Durability 

ICF foundations are excellent on durability metrics. In addition, since the insulated concrete forms are made of lasting insulation, you don’t have to worry about your insulation leaking out. 

ICF foundations surround the entire concrete with a layer of insulation. The added insulation stops cold air from passing through the concrete as rapidly as a conventionally-poured concrete foundation.

This added insulation effectively prevents frost formation on the concrete wall. It also protects your home from moisture and water damage during summers when the frost begins to melt. 

3. Greater Energy Efficiency 

Another great benefit of ICF foundations is that they offer high thermal insulation and can minimize or even remove the need for traditional thermal insulation.

Because of their high level of energy efficiency, houses with ICF foundations can fairly easily attain an ‘A’ rating. Moreover, the increased energy efficiency ensures your home needs less energy, reducing utility bills.

Houses built with ICF foundations require almost 44% less energy to heat and 32% less energy to cool than conventional structures. The larger your home, the more the savings.

In colder areas of the US and Canada, heating savings will be more, and cooling savings will be comparatively lower. In contrast, cooling savings will be more, and heating savings will be relatively lower in hotter regions.  

4. More Comfort

If you’re planning to have a basement suite or basement room, an ICF foundation will result in a considerable difference. 

For instance, ICF foundations create a more comfortable, drier, warmer experience for those who live in the basement. Since they are resistant to mold and moisture, the air quality in an insulated concrete form basement is much higher.

This kind of foundation even absorbs and releases heat energy round the clock, which helps in stabilizing the room temperature. 

5. Acoustic Insulation 

ICF foundations might be a good choice if you reside in a noisy neighborhood but want a peaceful home environment. 

Unlike other conventional building methods that consider soundproofing an afterthought, ICF offers it naturally.

ICF blocks used for building result in thick, solid walls that do not allow noise to penetrate. Additionally, insulated concrete form foundations are even helpful in decreasing noise transmission. This characteristic helps to keep noise out of your basement. 

Insulated concrete form isn’t just a great option for houses where peace and quiet are necessary but also excellent for commercial properties, such as movie theatres, where soundproofing is imperative to the building’s primary function.

6. Lower Material Cost 

You cut down on material costs when building with ICF foundations or walls due to the interlocking blocks. Cost reduction results because ICF uses around 10% less concrete than conventional straight forms. 

7. No Need for Specialty Tradespeople

You do not need specialty tradespeople to construct ICF walls as your framing crew can easily take care of the job. That said, it is always best to hire a team with some level of experience working with insulated concrete forms. 

Drawbacks of ICF Foundations

Despite a multitude of benefits, ICF foundations do have certain drawbacks too. Here are some of the most important ones you need to know before investing in ICF construction. 

1. Need for Waterproofing 

You will have to apply a waterproofing layer to the outside of the ICF blocks. The best technique for this is to precut the peel-and-stick membrane to the dimensions of the foundation, roll it up again, paste its edges to the walls, and gradually unroll it while applying. If you follow this technique, you can quickly complete the waterproofing job single-handedly. 

2. Higher Costs

Cost can be a problem when deciding between traditional or ICF foundations. If you opt for an ICF foundation, keep in mind that you will not be able to cut corners to complete the job at a lower cost. 

What Are Poured Foundations?

A ‘traditionally-poured’ foundation is basically a concrete foundation poured in situ. It features concrete walls that are eight or ten inches thick and sit over spread footings.  

To construct a traditionally-poured concrete foundation, a builder will first create large forms to ensure the concrete stays in place after it is poured. Then they will set up the reinforcement, pour in the concrete mix, and let it cure.

A traditionally-poured concrete foundation at a construction site

Once the concrete has fully cured, the contractor will have to remove the formwork and continue other essential tasks such as insulation and dampproofing. 

Advantages of Poured Foundations

Here are some of the advantages of a poured foundation. 

1. Highly Durable 

Poured concrete foundations have the tensile strength of steel and the compressive strength of concrete to create a durable foundation that can easily last for generations.   

2. Fire-Resistance

These foundations do not contain organic or flammable matter. Thus, they can prevent the spread of fire. 

3. Keeps Termites Away 

Poured concrete foundations can effectively keep termites out. 

Termites can lead to significant destruction to wood-frame houses. However, concrete foundations aren’t vulnerable to these critters. 

Disadvantages of Poured Foundations

Here are some of the drawbacks of poured foundations. 

1. No Insulation 

Poured foundation offers minimal insulation. If you plan to convert your basement into a residential space, you will need to insulate the foundation according to your local building code. 

2. Facilitate Condensation 

Poured concrete foundations can facilitate condensations in areas that experience low temperatures. For example, if the exterior of the foundation is cold and the interior is warm, the wall can turn into a source of condensation. 

3. Possible Water Damage 

Concrete foundation walls are generally dampproof, not waterproof, meaning that the walls are not sufficiently secured from the groundwater.

If the poured concrete cracks, water can seep into the foundation, requiring you to undertake comprehensive evaluation and repairs. 

4. Needs Formwork Rental 

You will need to rent, set up, and remove the forms that keep the concrete in shape while it cures. What’s more, the form’s height will perhaps not allow you to reach some of the more unusual wall height dimensions.  

What’s the Difference Between ICF and Poured Foundation?

The critical difference between poured and ICF foundations is that the forms turn into a permanent structure for the fixture (as they’re made using tough polystyrene insulation) in an ICF foundation. In contrast, poured foundations are made using plywood forms later removed.

The insulation is installed on the wall that faces the interior once the concrete has fully cured. Moreover, ICF foundations use more rebar, which improves tensile strength and offers increased protection from high winds and other elements. 

Insulated concrete forms prevent the concrete from freezing which safeguards it from moisture and frost, reducing the risk of mold and rot. 

Last Few Words

Both ICF foundations and traditionally-poured concrete are excellent ways to construct foundations, and you might opt for either one depending on your specific situation. Here is a quick guide to help you decide.

ICF foundations are suitable when:

  • You plan to convert your basement into a residential space. 
  • You are building in a cold climate. 
  • You need long-term savings on your energy bills.

Conversely, a poured foundation might be more suitable if:

  • You plan to use your basement as a storage room. 
  • You are on a tight budget.
  • You are building in an area that experiences a mild climate.

Best of luck in your endeavors! We know you’ll make the right decision for you.

One Comment

  1. Great post! As a homeowner in the process of building a new home, I’m finding this information incredibly helpful. ICF foundations have been gaining popularity in recent years, and it’s great to see a detailed overview of what they entail. Thank you for sharing your expertise!

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