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How to form concrete walls

In those parts of the country where the frost line is deep and basements are the norm, foundations are typically built by specialty subs, who can afford to stock the necessary forms because they use them every day. But in places where the frost line is shallow and the ground never freezes, it’s not uncommon for general contractors to form and place shallow foundations themselves.

That’s the case near the coast in Northern California. There, foundations commonly consist of shallow concrete footings and stem walls, which are typically just tall enough to create a crawl space under the floor joists. For this article, we turned to a video by Dave Osland, in which he explains his method for forming the footings and stem walls together and placing the concrete for both in a single pour. Osland’s fast and efficient system gives him control over his schedule and makes for smooth sailing once the framing starts.

How to form concrete walls

In areas with a shallow frost line and stable soil, carefully excavated trenches often serve as footings forms [1] , and enable “monolithic” pours, in which footing and wall concrete are placed together. Horizontal 2x8s stacked on edge are screwed to wood 1×2 vertical uprights to form the walls [2] . The bottom of the walls forms are set above the bottom of the trench at top-of-footing elevation.

How to form concrete walls

Forming and Bracing

Forming begins after the site has been scraped off to remove topsoil, vegetation, and other organic matter. Concrete footing trenches for the entire structure are machine excavated to accommodate 18×18-inch footings designed for a two-story structure [1] . Although the footings could be formed using 2-by stock, the required footing depth is typically shallow enough and the soil stable enough to permit trench footings, in which the walls of the excavation retain the concrete.

Wall forms consist of horizontal 2x8s stacked on edge and fastened to wood 1×2 vertical uprights [2] . Like most contractors, Osland used to fasten everything with duplex nails, but the advent of cordless screw guns changed all that. “We use screws to put everything together,” says Osland. “That way it comes apart easily, and if you need to adjust something you can just unscrew a board and reset it … There’s not a nail in this whole system here.”

Wall forms are held together with the same type of slotted, flat metal ties used in reusable concrete forms. The ties, which also double as supports for rebar, are placed at regular intervals along the top of each course of 2×8 boards, and locked in place with metal wedges on both sides [3] . Osland cuts the tops off of all of the vertical stakes, as well as the diagonal “kickers” used to brace the wall forms. “That’s one reason I like wooden stakes as opposed to steel stakes,” he says. “There’s nothing in the way later when you go to rod this thing off.”

Osland does a couple of things during forming that also make his work easier later on. The wooden spreaders used to maintain an 8-inch space between inner and outer wall forms are drilled and placed to position the many anchor bolts required by seismic codes [4] . Each anchor bolt is held in place by the nut, which is threaded as needed to suspend the bolt at the proper height. And to keep the bolts from being encased in concrete during the pour, Osland wraps the exposed threads with aluminum foil. For the same reason, he also wraps the tops of the Simpson holdowns, which are positioned using Anchormate anchor bolt holders .

How to form concrete walls

Spacing between inner and outer courses of wall forms is maintained using slotted metal form ties held in place with reusable metal wedges [3] . Spacing for the top course is maintained using wood 1-by spreaders, which are also drilled to position anchor bolts [4] . The tops of both the anchor bolts and the seismic holddowns are wrapped with aluminum foil to keep the nuts from being encased in concrete. Wood stakes and braces are trimmed flush to make it easier to strike the concrete later.

How to form concrete walls

Placing Concrete

Using a concrete pump, Osland and his crew first place the footings using very stiff concrete [5] . This mix sets up fairly quickly, providing support for the wall concrete [6] , which has more slump and is placed in a second pass. “We like to wet it up a little bit,” Osland says, “because then it fills up nice without any voids.” Voids are also minimized by vibrating the concrete as it is placed.

How to form concrete walls

Footings are placed first using a very stiff concrete mix [5] that will set up quickly and support the wall concrete. Wall concrete is placed with more slump and is vibrated to minimize voids [6] .

How to form concrete walls

Stripping Forms

The first step in stripping the forms takes place about an hour after the wall pour is complete. By this time, the wall concrete is stiff enough to stay in place while the crew removes the vertical 1×2 stakes—which otherwise would be locked into the footing concrete. The rest of the forms are stripped the next day, beginning with removal of the form tie wedges. They are salvaged for reuse [7] . Later, the form ties are either snapped off or bent down against the concrete wall. Using screws to build the forms pays off when it comes to removing the spreaders and kickers [8] . So does the aluminum foil, which makes it easy to unscrew the anchor bolt nuts and slip the spreaders off.

The crew also uses this time to inspect the foundation for any high spots along the wall. In this case, the top of the wall was struck very cleanly. “But the concrete is still relatively soft,” says Osland, “so if there’s a chunk of something [that’s high] you can [easily] straighten it out.” Finally all of the 2×8 form boards are sorted and stacked for reuse as floor joists [9] .

“We’re really happy there are no voids in here,” says Osland. “We took the time to get everything set right, [and] we had enough men on the job. You can’t ever have too many people on a job.”

How to form concrete walls

Forms are stripped the next day, beginning with the removal of form tie wedges, which are salvaged for reuse [7] . Spreaders come away easily after the screws and anchor bolt nuts are removed [8] , and kickers are salvaged for future use. All of the 2×8 form boards are sorted and stacked for reuse as floor joists [9] .

How to form concrete walls

Site-built panels that hold up under the stress of concrete.

Stop the pour!” The words echoed through the basement, loud enough to be heard over the transit-mix truck’s engine and the grinding pulse of the pumper.

“I’ve heard that before,” said the driver to nobody in particular. “That’s the cry of panic.”

The problem started when a snap tie snapped at the wrong time. My friend Charles, a builder who specializes in remodeling, was used to building his forms with plywood and snap ties. He’d never had a problem with the system and didn’t bother sizing the ties or spacing them to suit different circumstances. He used what he had on hand, and it always held together.

But this time the concrete dispatcher did him a favor by sending three truckloads of concrete in quick succession (he wanted to make up for a year’s worth of late deliveries, and it was a slow day at the yard). Filled quickly to their tops, the forms strained against the weight of the soupy concrete. One of the ties popped, and the forms bulged outward. The adjacent ties, already at their limit and now having to pick up the load of the failed tie began to pop in quick succession. In the blink of an eye, the form unzipped, engulfing the laundry room, the water heater and the new furnace in 20 yards of fresh concrete.

Why did the forms fail? Was a tie left out? Were they too far apart? Or was the wall poured too fast? Would stronger ties have made a difference?

In my experience, most carpenters have good instincts when it comes to working with concrete. They know how to build forms and how to brace them against the imposing loads brought to bear by truckloads of fresh transit mix. But I don’t know many carpenters who understand the criteria that govern form designs. Few carpenters know what the proper pour rate is or how to proportion the forms to achieve economy in material. Most carpenters overbuild the forms and hope that they’ll hang together. Using a form that is significantly overdesigned is almost as bad as pushing an underdesigned form to failure. Both practices waste money, and in the case of failure, somebody might get hurt.

I work for a large general engineering firm in Los Angeles, California, and along with several other engineers, spend a portion of my time designing site-built concrete forms, some of which are very complex. But you don’t have to be an engineer to size the forms for straightforward pours—even the 8 ft. to l0 ft. walls that are typically cast for basements or retaining walls. What is necessary is an understanding of what a form should do, what forces are going to be acting on it, what materials are available for building the form and the limitations of those materials. Once you’ve got a handle on those variables, you can use the table below in the PDF to design your own forms.

For more information on how to design forms for concrete walls, click the View button below

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How to form concrete walls

Many contractors shy away from poured concrete, preferring to use CMU block with a plastered face. The risk of cracking in poured walls and the difficulty in repairing them makes block and plaster a more forgiving choice. This simple retaining wall utilizes a beautiful travertine stone cap upgrade.

Perhaps the finest examples of poured concrete walls can be seen every day along freeways where these structures are constructed on a massive scale. Watch any of these in process and you get a real appreciation for the skill required to form and pour a perfect wall. There are so many things that can go wrong in this process that it’s a difficult solution for residential landscape retaining walls.

  • Pro Tip: With poured concrete, you have to form in the negative, which can be a visual challenge. Block walls are built the positive all the time. If there’s a problem, we’ll see it right away. –Joseph Heuttl, Huettl Landscape Architecture in Walnut Creek, CA

Concrete Retaining Wall

How to form concrete walls

Poured concrete walls can be tricky to install, but look great with the architectural elements of a modern house.

Challenges for Concrete Retaining Walls

Most landscape contractors in areas of heavy rainfall or weather extremes avoid fine poured concrete work due to its challenges. Woody of Woody’s Custom Landscaping in rainy Vancouver, Washington does not recommend them for his projects. “When a concrete wall fails, it’s over. You have to build a new wall from scratch. Cracks are a huge problem – sure you can patch them but it’s hard to do. We consider the entire wall a loss because there’s no long term fix.” They are growing however in scattered mild climate enclaves such as southern California where modern design has brought a new wave of interest in this type of retaining wall.

Woody also stresses the importance of skilled concrete contractors. “The forms have to be immaculate. Otherwise you risk a wave or bulge in the wall. Where strict geometric forms are required, this kind of variation can be disastrous. Plus, the concrete itself has to be tamped perfectly if the wall is to bear a smooth surface. That’s hard to do with retaining walls because there is so much steel inside – it’s a whole lot of rebar tied into enormous footings.”

Poured Concrete vs. CMUs

This unforgiving nature of poured concrete explains why they are not often seen in residential landscapes. The evolution of more reliable retaining wall systems and the use of a CMU core allows the landscaper to achieve a great look without the cost or risk. However, some landscape architects and their clients who extend poured concrete architectural elements of a modern house must bring this material into their exterior walls and retaining walls.

Landscape Architect Joseph Huettl of Walnut Creek, California uses both of these methods. “There’s no question, an 8″ concrete wall is stronger than an 8″ block wall. You can use admixtures to help adjust to climatic issues for greater control of moisture intrusion. For walls under four feet, we use a Simpson tie system that our crews have mastered to allow us to pour walls quickly with high degree of success. The downside is that it takes a long time to build the forms, but once they’re up and the pour is complete, there’s nothing more to do. Plus, you don’t see the error until you pull the forms.”

How to form concrete walls

This beautiful small home entry combines plaster with travertine paving and wall caps. This demonstrates how elegant simple solutions can be that may prove more sustainable over time. A block wall with a plaster face can be easily repaired or replastered should there be any discoloration or water seepage from planters at the top. Planters in direct contact with retaining walls can be a risky choice due to the danger of water seepage through the wall to compromise its structural core and discolor the face.

The majority of landscapers today can achieve a similar look with a block CMU core plastered to resemble poured concrete. “We use block with a hard trowel plaster that looks identical to poured concrete. We also like to use smooth stucco that also looks just as good. But we’ve had some difficulty with cracking of these coatings on block walls at the mortar joints underneath if the masonry isn’t top notch.”

Footings & Reinforcement for Concrete Retaining Walls

If poured concrete is to be used, it should be designed by a landscape architect to ensure there is adequate footings and steel. For example, if waterproofing fails and moisture causes the face of the wall to discolor, however slightly, the plaster may be stripped, the seepage repaired and the wall recovered to look like new. Comparatively, such a problem with poured concrete is disastrous. Poured concrete walls also offer the opportunity to create a board-formed finish look. Read more about how to achieve board-formed concrete. It’s also possible to achieve very organic and creative finishes such as this unique vertical concrete wall.

The footing will extend outwards from the face of the wall or out the back depending on the type specified by architect or engineer. This does have some influence on the adjacent planting at the base of the face of the wall. Overly large footings that extend considerable distance out from the wall can create drainage problems for lawns. It also prevents excavation of planting holes of shrubs and trees. For this reason, your designer will coordinate the footing size and dimensions with paving or planting that runs along the face of the retaining wall to accommodate any limitations.

When you choose WTF concrete forms, you are investing in the highest quality, most durable concrete forms for sale in the market today. Our quality control extends beyond the manufacturing plant, including custom design and engineering, constant reevaluation of our products, regular communication with contractors, builders and distributors, and on-site training and inspections. We manufacture concrete forms designed to meet your needs, not ours.

Our concrete forms use state-of-the-art robotics welding system which extends the life of welds on our full concrete forms. These concrete forms receive the most concrete placement pressure. A soft alloy weld wire is utilized in the concrete form weld process. This ensures greater flexibility without sacrificing strength when the concrete form is in use. This greatly reduces, if not eliminates, broken welds.

8-8 / 8-24 Concrete Forms

This hole pattern makes the 8-8 / 8-24 ideal in markets converting from block to poured concrete walls. This allows the contractor to easily accomplish 8″ jumps.

6-12 Concrete Forms

How to form concrete walls

The 6/12 hole pattern allows the contractor to easily accomplish 12″ jumps. It is available in widths from 36″ – 1″ and heights up to 120 inches.

6-12 Double Bracing

Every Panel is Built to Last…In addition to the 6-12 we offer 6-12 Double Bracing. This upgrade is constructed with a double 1 x 2 tube providing less weight, easier handling and more nailing area.

Super Light Concrete Forms

Is weight an issue with your concrete forms? Then the Super Light concrete form is for you. Consistent care increases the longevity of this panel.

Commercial Concrete Forms

Accurate, Reliable…Because this commercial concrete form is engineered for minimal deflection and pillowcasing, it is ideal for commercial applications requiring the flattest possible wall surface.

Brick Concrete Forms

Looks like brick…Feels like brick… WTF’s natural “brick-look” forms leave a lasting impression. Available in Smooth Brick, Textured Brick and VertiBrick.

Block Concrete Forms

How to form concrete walls

Looks like block …Feels like block… WTF’s natural “split block-look” forms leave a lasting impression. Residential or commercial applications can easily be painted or two-toned for a decorative look.

Ashlar Stone Concrete Forms

WTF’s natural “Ashlar stone-look” forms leave a lasting impression. Residential or commercial applications can easily be painted or stained for a decorative look.

Gang Adapters

The WTF Gang Adapter enables a contractor to create gangs utilizing 36″ wide aluminum concrete forms. The WTF Gang Adapter allows contractors to easily gang aluminum forms together.

Big Panel

Just as its name implies, these forms are built large. The WTF Big Panel is ideal for repetitive tall concrete wall construction.

Wall-Ties & Forms, Inc.
4000 Bonner Industrial Drive
Shawnee, KS 66226

Home » Concrete Walls Cast-In-Place

Concrete Walls Provide a Stronger & Drier Basement

Energy Performance

Cast-In or otherwise known as Pour-In walls are a technique in which the concrete is poured in to form the foundation. Cast-In-Place walls are also energy efficient. The concrete in your basement is an excellent “heat sink.” Once the wall reaches ambient room temperature, it retains its heat even if the air cools because it acts as a mild insulator. You can add insulation to the wall (sandwich or exterior) and below the slab to create a very stable temperature environment.

Structural Integrity

The cast-in walls are also structurally superior because they have better lateral strength, which means more resistance to pressure. Solid concrete walls have greater strength than other materials and methods with the ability to resist:

  • soil pressure
  • water pressure
  • construction loads

Faster Construction Time

They are also the quickest method of foundation construction, because of the quick simple process. An entire foundation is typically installed in several working days. This fast construction cycle means that carpenters and other trades can start to work earlier.

Durability

Our walls have fewer problems and are more serviceable too. The durability of concrete walls is unparalleled as well. Concrete foundation walls are resistant to many things such as:

  • fire and wind
  • insects
  • decay, mold & mildew
  • efflorescence

Proven Performance

Concrete is the most widely used construction material in the world being used for centuries. Cast-In-Place concrete walls and concrete as a building material have proven themselves time and time again.

Higher Resale Value

Solid Cast-in-Place concrete foundations have consistently higher resale value because of their quality and integrity – just ask your realtor.

Versatility

Our walls are versatile in terms of shape, height, dimensions, and cross section (brick ledges, etc.). The modular design of the forming systems and the nature of concrete allows for construction of complex forms and shapes including:

  • curved and angled walls
  • walls with an unlimited number of ins-and-outs,
  • steps and openings
  • walls with different textures/patterns

Sustainability

Balancing the effects of growth against its environmental impact, the sustainability of cast-in-place walls is enhanced when concrete is used for your foundation material because of its design and reliability.

Water Tightness

The Cast-In walls are also inherently water tight. Cast-In-Place walls are monolithic, (no joints) which means a drier basement. Water tightness is important because without that feature, the integrity of your whole foundation could be at stake.

TOPIC : 4. CONCRETE FORMWORK

INTRODUCTION: This topic teaches students the different types of concrete formwork which must be strong enough to withstand the pressure of the wet concrete.

Carefully select the chapters which are needed to meet the aim and the syllabus of the school.

4.1. Students must be able to make a simple formwork for a concrete slab. When possible demonstrate it on a small project. E.g. a watertank foundation.

4.2. Students should be able to identify the parts of a formwork for a concrete wall. They also should be able to describe the process of making a formwork for a concrete wall.

4.3. Students roust be able to name the parts of a stair, its correct measurements and describe the process of making the formwork for concrete stairs.

4.4. Students should know the correct names for the parts of the formwork for septic tanks and the correct measurements.

METHOD: Prepare photocopies of the drawings taken from this topic for the students for better understanding. After introducing the objectives of this topic, students take notes from the blackboard and glue the copies of the drawings in their trade theory books.

This topic might be difficult to demonstrate on an practical example because of the large amount of timber needed to do such a demonstration. However, if there is a building project within the school going on, take this opportunity to show the students the correct procedure for making such a formwork.

NOTE: At the end of this topic prepare a worksheet for the students to reinforce their knowledge.

Formwork is a temporary construction used to hold concrete in place while it sets. As concrete is very heavy, formwork must be solidly constructed and firmly braced and supported. To ease the removal of the formwork after the concrete is dry the sheating must be well oiled before pouring the concrete. The material used for sheating are boards, which have a thickness of 25 mm. In order to get a smooth surface or if a high wall is required, nowadays 19 mm plywood is often used. Wet the timber of the sheating before pouring concrete; this will, swell the timber and tighten the joints and thus prevent the escape of water from the mix. It will also prevent the too rapid drying of the outer part of the concrete by absorption of water by the boards.

4.1. Formwork for concrete slab

A slab is made for concrete path, driveways, tank stands, floors etc. As slabs are relatively thin the pressure on the formwork is low, demanding a less solid construction. The soil is slightly excavated and the pegs driven into the ground at approximately 600 mm intervals. The boards are nailed on the pegs.

a) Procedure for making a concrete slab:

First place the pre-assembled wooden forms with the aid of building rope to the correct height and line. If it is necessary brace the forms strongly so they will not weaken when they are filled with concrete. Measure diagonals to ensure squareness. Fill in the wooden forms with concrete.

b) Joining concrete slab:

Very seldom can any type of concrete construction be built without joints. There are two types of joints in concrete work – construction joint and contraction joint.

4.2. Formwork for concrete wall

Formwork for a concrete wall is normally built up on both sides of the wall. Reinforcement bars are laid on wires before the spreaders are placed and the wall is tied. The studs are approximately 600 mm apart. All studs are braced.

a) Formwork for high concrete wall:

There are two methods of fixing wall forms, one with “wales” and the other without wales.

b) Formwork for a concrete wall an a slop:

On sloping ground an earth face may form one side of the formwork.

c) Formwork for a footing wall:

4.3. Formwork for concrete stairs

Concrete stairs also require temporary formwork and the necessary check timber supports. As with timber stairs, check the height from floor to floor as the first step in the preparation of a set out. Divide this total rise into a suitable number of risers and then calculate the proportionate size to the go, as described in the chapter dealing with timber stairs. A flight of stairs should be easy and comfortable to climb. Certain dimensions must be followed to ensure this.

– Maximum rise is 190 mm.

– Minimum going is 255 mm.

– One going plus two rises should equal 585 mm to 625 mm.

– Before pouring the concrete reinforcing mesh is laid in position.

4.4. Formwork for septic tank

The excavation for a septic tank must be as accurate as possible (sides must be plumb and hole square) as the sides of the hole form one side of the formwork. Cut and test assemble the formwork above ground. The sides should be made in two sections to make handling easier. Remember to make provisions for drain pipes. The bottom of the septic tank is sloping. Use the bottom edge of the side panel to get the exact slope. The bottom slab is poured first using bottom edge of side panel for accuracy. When concrete has set slightly the formwork is placed and the sides poured. The top edge of the tank is 100 mm above ground level to prevent rainwater entering. The sheating usually used for septic tank is 19 mm plywood.

How to form concrete walls

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How to form concrete walls

How to form concrete walls

How to form concrete walls

Has any of you ever thought of making your own concrete wall. Well here you go, I have done it myself. It’s easy peasy if you know how to! Here is a little tutorial of how to make your own concrete wall.

Step 1: STEP 1 – Before You Start

Preparing the wall before you start is essential. First of all you need to make sure it’s clean and secured with masking tape, after that you can start doing the measurements. It’s good to know how would you like to divide your wall before you put the grid on. I’ve decided to divide mine into nine equal pieces. I simply left some marks on the masking tape, so it was really easy to connect them when I needed. Having all of these done I applied some primer using a paintbrush and waited the next 12 hrs for it to dry.

Step 2: STEP 2 – Application

Depending on what type of concrete mixture are you using always follow the instruction given by the producer! I had to mix mine first and then I started the application using finishing trowel and stripping knife (this one was only used to put some mixture on a trowel, but you can use any other tool that will be handy for you). The whole process itself is very easy, but you need to be quick if you’ve got bigger surface to cover, because concrete dries out fast. So remember to allow yourself extra time for smoothing before it gets completely dry.You need to apply only a thin layer of mixture at the time (no bigger than 1-2 mm!). To get the real concrete effect you’ve got to stick the trowel in and out to the wet surface. Then let it dry for about 30 minutes.

Step 3: STEP 3 – Smoothing

Now when the whole wall is covered with concrete you can start smoothing it. Use the same finishing trowel to do that, but this time try to smooth the surface instead of making it rough. Don’t worry if the mixture gets a little bit too dry, you can always spray it with some water, but remember not to leave it for too long. When it gets completely dry you won’t be able to do anything!

Step 4: STEP 4 – Finishing

Now when the wall is almost done, but not completely dry yet you can draw the lines that you have marked at the very beginning. The best way to do that is to use a long spirit level and a spanner end. It’s good if you can ask someone for help in here, if not just try to be very patient and precise. Once you make a mistake at this stage it can’t be reversible! After all of these is done don’t forget to add characteristic concrete panel circles. To do that use a paint roller with round end. Simply put it to the wall in the right place, turn around and here we go it’s all done!

Step 5: STEP 5 – Drying

In the end let it dry for at least 24hrs and you may start enjoying your concrete wall.

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5 Comments

How to form concrete walls

I want to do this but as a former remodeling contractor I has some big concerns. For one, I’d prefer to possibly make some actual precast tile that is

24″ x 48″ in size or smaller around 18″ x 36″ and at 1/2 to 5/8″ thick with chicken wire or lightweight expanded screen. And then I would anchor the tile to the studs with 1/4″ bolts at

2″ long (for at least 1″ of bite into wood studs). And I would specifically use fiber reinforced cement (not concrete) for this project. I do think the general “trowel on” method used in this instructable is of course easier, but my major concern is cracking and shear weight. Let me explain;

With the method presented in this instructable it makes no mention of the best product to use, nor does it mention it’s long term ability to stick to the wall, the total shear weight, etc. To be clear, if you just smear on regular cement, or even fiber-reinforced cement on a standard wall that is smooth drywall with latex paint, there is absolutely no guarantee that it’s going to stick and not lift away from the wall, crack, and potentially fall off. There is no bonding substrate. So at very minimum, if taking this approach, I would use an expanded aluminum lathe sheet (like is used for exterior stucco), screw that tightly into the studs (so get a stud finder) and then trowel on the cement to about a 1/2″ to 1.5cm thickness.

The tighter/flatter you can get the lathe sheet, the thinner you could go with the cement application. So I hope anyone that reads this will understand that you can’t just smear concrete or cement on any wall and expect it to easily stick and not crack or eventually fall off. I’m sorry but cement, especially thin cement, just doesn’t work that way. Not unless it’s got a lot of fiberglass and acrylic (glue essentially) mixed in to help it. And even then. I’d personally still use the lathe screen to structurally reinforce it.

And again, the same basic methodology would be with making individual tiles that bolt to the wall. All cement and or concrete needs some type of structural reinforcement. If you don’t want to do it right, with actual cement, then look at faux paint techniques or cement colored wall plasters instead which are essentially more like a drywall mud.

How to form concrete walls

Insulated concrete forms are essential building blocks for concrete wall reinforcement. These innovative wall forms also regulate interior temperatures of buildings, dramatically impact energy costs, and significantly reduce outdoor sound pollution. The one downside to using insulated concrete forms may not necessarily be due to the ICFs themselves, but rather how they’re installed and where they are used.

What Are Insulated Concrete Forms?

Insulated concrete forms (ICFs) are forms designed for cast-in-place, reinforced concrete walls that date back to the 1940s and 1950s. The initial conception of the ICF first occurred after World War II, when Swiss engineers began holding cement walls together with treated blocks of wood. After that, the idea was adopted by chemical companies who developed plastic foams. This was later further developed by Jean-Louis Béliveau to regulate the temperature in his parents’ Florida home. The purpose of these forms is to be permanent wall supports that create space to run wiring and plumbing, provide thermal and acoustic insulation, and be the interior side for exterior walls.

Essentially, an ICF is an H-shaped structure that allows for two concrete walls to be cast in-between layers of insulation whilst keeping an open-air channel between the two walls. These are strong and sturdy systems that can be particularly energy-efficient and used in a wide variety of buildings types ranging from residential to commercial to industrial. While the final product results in a slightly wider wall, the finish is often identical to typical construction.

If you are interested in upgrading the walls of a particular building or space and are considering insulated concrete forms, here are a few pros and cons that you should consider before constructing.

How to form concrete walls

Photo By Lutsenko_Oleksandr

Pros

Strong Walls

Adding an insulated concrete form has the primary advantage of strengthening a building’s walls. The poured concrete hardens around the ICFs, which then reinforces the wall and reduces its vulnerability to vertical and horizontal forces. Depending on whether the frame of the ICF is flat or grid, the wall can be made even stronger by the frequency and rigidity of the inner connectors. Unlike a normal cement fixture, the pockets and ICFs between the walls actually increase the structure’s strength and durability

Energy Efficient

One of the most appealing aspects of using insulated concrete forms is that it has the potential to significantly reduce the heating and cooling costs of a particular building. That’s also the most impressive feature of ICF walls; they can release heat in the summer and store heat in the winter. In some instances, ICFs are estimated to save about 20% of total energy costs.

As a comparison, the tightness around insulated concrete form walls is much tighter than those of compatible window and door frames. If your insulated concrete forms have a lifespan of 100 years, with no degradation, a single-family ICF home could save up to 110 tons of carbon dioxide compared to traditional wood-framed homes. CO2 savings that high would create a net positive carbon footprint for the cement and the ICFs.

Sound Reduction and Temperature Stability

Through a sandwich of materials, insulated concrete forms are able to act as a sound barrier, protecting the interior of the house from outdoor noises. When a massive material, in concrete, is combined with a light one like foam, fluctuations in temperature, air filtration, and sound are able to be dramatically reduced. The layer of foam that insulates the entirety of an ICF wall helps keep it the same temperature throughout – essentially eliminating “cold spots” that occur in frame walls between insulation gaps or around the studs. In terms of sound reduction, walls with insulated concrete forms allow for only one-eighth the amount of sound to be penetrated as that of a wood frame wall.

Saves on Material Costs

By integrating insulated concrete forms into various walls or parts of the construction process, you would be able to set walls and foundations with 10% less concrete . ICF, when delivered to the job site, often comes as straight-form blocks that have already been assembled. This can eliminate a couple of inches of thickness compared to traditional straight form builds, which in some instances could net you a 25% increase in savings on materials and expenses.

How to form concrete walls

Photo By Radovan1

Cons

Don’t Work As Well In Cold Climates

In theory, these walls act as strong insulators of heat at colder exterior temperatures. However, this doesn’t account for the amount of heat that transfers outside. Insulated concrete forms are designed to transfer heat out of the structure so that outdoor temperatures don’t negatively affect the curing process of the concrete. Therefore, ICFs work much better in more tropical climates where the heat transfer and insulation can keep a home cool during the day while also making it comfortably warm at night.

Could Be More Costly Than Expected

The savings regarding insulated concrete forms is undeniable; however, that’s assuming you have the affordable labor to install it. If you decide to incorporate ICFs into your project’s walls or foundation, you might be looking at overall costs that are more expensive than conventional processes. Insulated concrete forms require specialized labor; if your worksite is located in an area with very few contractors capable of incorporating ICF, then you may want to switch to cheaper methods.

Some Projects May Not Be Able To Incorporate Rebar Reinforcement

A lot of the strength that insulated concrete form walls possess comes from the addition of rebar. These moldable steel wires are excellent for fitting between the seams of the interior grid and reinforcing the concrete. Unfortunately, many new ICFs include plastic connectors, which act as cheaper and more flexible reinforcement wires, which leaves very little space for the addition of rebar. This is more troubling on corners, where ICFs can be vulnerable to wall seams and other structural instability.

If you have access to specialty contractors or are indifferent to installation costs, insulated concrete forms are the ideal choice for any concrete wall or foundation. These forms improve temperature regulation, reduce material cost, dampen exterior sounds, increase wall strength, and save you massive amounts of energy. If you need help managing the specialty contractors required to design and install ICF walls, then check out eSub’s construction project management software. Just like ICF, eSub is a smart and essential investment for any construction job.

Contact us for an eSUB CLOUD demo and to learn more about how project management software developed for subcontractors can streamline your processes for more profits and less chaos.

How to form concrete walls

After two and a half years in my shed-shop (I cannot believe it’s been that long already), it is finally time for a shakeup in this little space. The past few years in here have been incredible, but it’s getting a little crowded in here. I also underestimated just how big my little business would grow in this space (thanks to all of you)! So, it’s time to make this shed work better as a workshop and a space to document my content with all of you… starting with my tool wall! I’ve been wanted to create a DIY concrete accent wall in my life for a while now, so why not do it in the workshop! This is a project that works well for any space (not just a workshop), and I can’t wait to show you how I made it happen!

How To Make A Concrete Accent Wall

This post is sponsored by The Home Depot and is part of the ProSpective program. It contains affiliate links. For my full disclosure & sponsorship policy, click here.

Want to see this project in action? Check it out on my YouTube channel and make sure to subscribe!

I seriously cannot wait to own a house. There are so many projects I want to be able to tackle at some point. Luckily, a concrete accent wall has been on that list for a while and now I get to tackle it in my shop space!

How to form concrete walls

Now, I installed this accent wall over exposed studs, but this is a tutorial that can easily be used over drywall as well!

Ready to get started? Let’s do this!

What I Used:

How to form concrete walls

* quantity of these materials will depend on your particular project

The Steps:

1. First, I hung the cement board with the cement board screws and made sure it was attached to the studs. I had a few studs with screw heads hanging out, so I cut them using my Dremel Rotary Tool and metal cutting wheel. With any project in which you hang boards on studs, you want the studs to be clean and flush!

How to form concrete walls

I also added blocking to any portion of the wall that needed some extra support.

How to form concrete walls

2. Next, I cut any pieces I needed to trim with a cement board knife. You can see this in action in my YouTube video!

How to form concrete walls

How to form concrete walls

3. Next, I taped the seams and mudded them using a thin layer of feathering cement.

How to form concrete walls

How to form concrete walls

4. After allowing the seams to dry, it was time to start adding my cement. I followed the instructions on the bag of the product that I used and mixed the cement to a frosting-like consistency.

How to form concrete walls

I then troweled the cement onto the cement board. I didn’t pay too much attention to the pattern. Instead, I randomly added swooshes (technical term) until it looked organic. This is up to personal taste though!

How to form concrete walls

5. After letting the wall dry overnight, I came back the next day and used my sander with 80 grit sandpaper to lightly sand the wall and blend all of the coloring and texture together.

How to form concrete walls

6. I then just wiped down the wall with a wet mop (you can use a cloth, I’m just short) and allowed the wall to dry. You can seal your cement wall after this step, if you’d like, but I wanted mine to stay as matte as possible, so I skipped this step.

How to form concrete walls

I am so stoked with the way this wall turned out and cannot wait to start getting the rest of this space in order!