The foundation and walls of a concrete home are usually created through the use of a temporary form. When choosing insulated concrete forms, the framework stays in place, serving as a permanent form of insulation to compliment the building process.
You will discover that the pros and cons of insulated concrete forms offer improved energy efficiency levels and better structural strength, but there may be some problems to manage along the way.
List of the Pros of Insulated Concrete Forms
1. You get to benefit from the strength of a reinforced concrete wall.
The primary advantage that you receive when using insulated concrete forms is the added structural strength that comes when you can use a foundational reinforced concrete wall. This process allows you to use one simple operation to gain all of the benefits that come with the structural qualities of this material. That includes the insulation and air-sealing qualities of a SIPS wall when the work is performed correctly.
2. It saves on your material costs when building walls or foundations.
When insulated concrete forms are part of the construction process, then you will typically see a waffle-style set of plans that the contractor uses for their work. By taking this approach to the walls or foundation, you’ll use about 10% less concrete than if you used the traditional straight forms for the work.
Choosing ICF also means that you can choose straight-form blocks that go together easily to give you more strength with less width. You can shave off two full inches of thickness when choosing insulated concrete forms to build instead of the traditional straight forms – a savings of 25% in materials and expenses.
3. ICFs can improve the curing time of the concrete.
If you choose insulated concrete forms, then you can experience an improvement in your curing time of up to 25% as well. It gives you opportunities to reinforce your structure that other building methods don’t offer either, which means there is more value in the work even though it takes significantly less time to produce results.
4. There is less setup time to schedule with insulated concrete forms.
Builders that choose insulated concrete forms for their projects can create a sturdy, reliable frame for their concrete in a fraction of the time it takes to build out a straight form. Once the outline of the pour is fully staked, a crew can take care of the building and setting process in a single afternoon. There might be some added costs to consider because it requires a specialty skill to get the work done correctly, you can find some cost savings in the lower amount of time involved in the labor
5. Insulated concrete forms allow you to install wiring and plumbing.
If you prefer to use insulated concrete forms for your construction needs, then you’re not sacrificing the ability to install your wiring and plumbing systems. Builders can cut groves in the foam so that any necessary components can be part of the construction process. Your pipes or wires would go through the segment as they would with the traditional structures. The best practice is then to use spray-foam insulation to secure any leaks, and then caulking, flashing, or weatherproofing to shore up the installation.
This advantage allows the modern crawl space to become a usable area because it allows airflows to continue while giving owners access to the modern amenities they require.
6. You can still use rebar with ICF systems.
Once you have the entire form in place, insulated concrete forms allow you to insert rebar reinforcements for your concrete pour. This benefit allows you to continue taking advantage of the strength of reinforcement while getting to use the time advantages of the ICF system. Since every unit of the form interlocks with every other one, they can stack quickly to whatever shape is necessary for your project. They keep the concrete in place with only bracing assistance from the outside, which means there is an exceptional level of shock resistance present in the work.
7. The final appearance of the structure creates a natural look.
You can use all of the regular building processes with insulated concrete forms that you would with any other system once the materials dry into the desired shape. Builders can add stucco, stone, or bricks to the exterior of the structure to enhance its look and stability. Most siding materials work with ICF systems as well. When you add in the foam interior that most contractors use with this option, a structure receives three layers of strength at its shell, creating a foundation that excels in providing long-term supports.
8. This building method helps to protect the concrete while it cures.
The straight-line forms can increase the risk of air bubbles and other faults forming in the concrete, creating future problems that could require costly repairs. The insulated concrete forms help to reduce this risk because it protects the concrete while it cures. You can reduce the impact of stressors while still creating a solid mix with this material since you’re working the foundation and walls as you normally would using any other method.
9. It can improve the indoor air quality of your home.
Another benefit worth considering if you are looking at insulated concrete forms for your project is that the processes can improve the eventual indoor air quality of the final structure. You’ll receive more density in the final walls, which means less air can move through it since the final result is not as porous as it would be with other building options.
If you maximize the results of this benefit, then you can reduce your energy expenses by up to 70% – further adding to the cost savings you can experience. When built correctly, the structure can reduce dust and allergen pollution by up to 75%.
List of the Cons of Insulated Concrete Forms
1. Insulated concrete forms don’t work well in cold climates.
You’ll receive the most benefits when using insulated concrete forms in a warm, tropical environment because of the way that the heat transfers out of the structure. The footings and anchors support this process to ensure that the outside temperatures don’t impact the curing process. You don’t receive this benefit in a colder environment. There are times when the heat transfer out of the system could be problematic if you don’t want the structure to balance out in that way.
2. It doesn’t change the fact that the concrete needs to cure.
You can release insulated concrete forms to early just as you can the traditional straight-line option. If you leave the product to cure in the ICF, then you’ll typically see more strength with the final result. The only problem is that builders tend to release the forms too early, sometimes by as much as 24 hours, because they want to continue with their work.
Architects often stipulate thicker walls because of this disadvantage. If the concrete walls receive exposure 24 hours after pouring, even with quick-setting products, a thin structure could develop problems that a wide one would not.
3. There are cost considerations to look at with insulated concrete forms.
If you decide that insulated concrete forms are the best way to form the foundation or walls of your structure, then you can expect to pay about 40% more for the final result. Conventional processes are cheaper because they don’t require the same level of specialty labor. Although you get a vapor barrier and more insulation by using this system, scarcity is a significant factor in your final estimate. If there are only 1-3 contractors in your area using this process, then it will almost always be cheaper to take the traditional route.
4. ICF systems require a bracing process as part of the build.
Most insulated concrete forms require builders to use a bracing system that aligns the walls to be square and plumb. If you pour into the structure without this support, then there is a significant risk of the concrete blowing out through the interlocking mechanisms. You can still see leakage occur if the horizontal and vertical accesses are not correctly aligned with the overall frame.
The most laborious part of the building process when using ICF systems is usually the bracing, not the stacking that is necessary for a foundation or walls. Even if you get the bracing up correctly, you may see some lean in the structure that will need help to return to its correct positioning.
5. Walls built with insulated concrete forms have common seams.
One of the most common descriptions of insulated concrete form construction is that the process looks a lot like building with toy blocks. You must work from the corner of your design toward the middle of the project to ensure that a correct fit occurs. There are seams present in every wall, so you want to move them away from the corners – and that doesn’t always happen with ICF projects. You should create a seam that occurs in a strong point of the structure that you can reinforce with foam or caulk so that you can use the strength advantages of this technology.
If you fail to separate the seams, then you can actually weaken the wall before the building process is complete.
6. You may find it necessary to trim the ICF blocks.
The insulated concrete forms might be easy to stack and structure, but they are also a lot like working with tile. With grout and mortar, it is a fairly simple process to lay whole building products over a large space. When you get to the edges, then the work becomes tedious because you must measure and cut each item. ICF systems require the same process, especially when shippers accidentally create dents in the product.
There can also be manufacturing defects to manage that can prevent you from achieving the tightest fit possible with this building method. These disadvantages can cause leaks, force you into making more trims, and even wasting some blocks if they don’t receive the fit and finish necessary to work with your building project.
7. Some projects may not get to use rebar for strength reinforcement.
Many of the insulated concrete forms in use today provide plastic connectors and reinforcers that work to stabilize your walls or foundation during the pour. If you want to add rebar into the concrete to give it even more strength, then you may find that there isn’t enough room for the correct placement. This disadvantage occurs more often at the corners of your structure than in the middle of a wall, but it may occur at any point in the structure.
If you accidentally break one of the plastic supports while reinforcing the concrete, then you’ll need to stop the pour and correct the situation before continuing. This element of the product is an integral part of the stacking process, so it must take a priority.
8. There could be challenges with remodeling efforts in the future.
One of the overlooked disadvantages of using insulated concrete forms is that the houses built in this way can be challenging to remodel later on down the road. You’ll need to think carefully about the design of the structure since you can’t add a new door or a window without cutting through a concrete wall to make that happen. You even need to be considerate of the different plumbing and electrical installation points that are necessary to reduce the time-consuming problems of cutting into the wall.
9. It can reduce the amount of floor space inside of the structure.
Smaller homes don’t really benefit from insulated concrete forms because the added size of the walls reduces the amount of floor space that you receive. The walls of an ICF build provide several inches of rigid insulation and reinforced concrete, so they take up a lot more room than the traditional wooden frame.
You might also experience more problems with pest infestations because the foam used for the insulated concrete forms can provide a route to entry for insects. Some homeowners have even experienced groundwater coming through their walls. It is imperative that builders treat the products with an insecticide before completing the project, which means you might have more exposure to chemicals than you want with your new property.
10. There can be indoor humidity problems with an ICF home.
Because there is less airflow happening through the concrete thanks to the presence of the foam bracing, the indoor environment for these structures can become remarkably humid. You’ll encounter this issue at significant levels if the build continues while the concrete goes through the curing process. You may need to use a dehumidifier or an air conditioner to manage this issue so that you can stay comfortable.
Conclusion of the Pros and Cons of Insulated Concrete Forms
Insulated concrete forms provide a simple and effective alternative to the traditional work of building walls or a foundation. Once you get used to the steps that are necessary for a successful experience, a form can go up fairly quickly so that you can begin the pouring process. Then the foam blocks can act as an insulator to ensure that your exterior shell can provide you with the added support that may be necessary.
These insulated concrete forms pros and cons must be taken from an individualized standpoint because every location and climate can put different stressors on this structure. It can be challenging to pour since a mistake will cause an immediate blowout, but this process is also faster and more effective. That’s why the advantages usually win out when considering this building option.
Brandon Miller has a B.A. from the University of Texas at Austin. He is a seasoned writer who has written over one hundred articles, which have been read by over 500,000 people. If you have any comments or concerns about this blog post, then please contact the Green Garage team here.