Step-by-Step Guide to ICF House Construction & Installation
Building with ICFs is faster and more efficient than traditional wood framing. This guide covers the entire installation process, from excavation to the final pour.
Looking for block dimensions and specifications? View our BuildBlock Insulated Concrete Forms product page.
Building your new home is great, but building your new home with BuildBlock ICFs is even better.
The task of building your own home can be daunting. Luckily, BuildBlock is here to break down the different steps involved in the process. Here is a step-by-step overview of each part of the building process explaining each component with technical instructions.
How are ICF buildings constructed?
ICF buildings are constructed using a running bond interlocking manner with the most common size of 4 foot long and 16 inch high blocks. Height and length may vary in some instances depending on the manufacturer. Evenly spaced webs create a cavity that give the block its strength. The thickness or the width of the cavity can vary from 4 to 12 inches or more. The most common wall sizes are 6 and 8 inches. Most manufacturers offer corner blocks, 45-degree blocks, brick ledge forms and taper top blocks along with various accessories and fittings. Some blocks are fully-reversible, adding to the ease of construction. ICFs allow for unlimited design flexibility. You can easily construct radius walls, multiple elevations, and other architectural features using ICFs.
First, horizontal reinforcing (Rebar) is installed as the forms are being placed. Next, when walls become too high to reach from the ground, bracing or alignment systems made specifically for ICFs are installed. These bracing systems have foot plank brackets for the placement of the planking to complete the stacking of forms. The concrete is then poured, generally, one level at a time.
Vertical steel is placed before each pour and if the structure above is a continuation of ICFs, then a cold joint dowel would be placed to tie the next pour to the first. Most bracing systems have adjusting turnbuckles which allow the walls to be perfectly straightened as the pour is finished. Also, most companies offer training and technical support in addition to providing installer manuals, pre-engineered tables, CAD details, and engineering models.
The 22-Step ICF Installation Process
Phase 1: Site Preparation & Footings
After zoning and building permit requirements are met, prepare the site for footings or slab on grade construction.
Formwork is placed for footings as per local codes or as specified.
A pre-pour inspection may be required, check with local code officials. Place concrete in formwork. Care should be taken when consolidating concrete to eliminate voids or honeycombing.
Level footings make the whole building process easier. Take a little extra care here.
Place vertical reinforcing as specified or per local codes and/or the BuildBlock Engineering Manual found at buildblock.com
Once lines are snapped on footings, materials can be staged for faster installation.
Phase 2: Wall Stacking & Reinforcement
Step 7: First Course
Starting at a corner, begin stacking wall.
Step 8: Reinforcing & Layout
Place horizontal reinforcing as specified. Reverse corners each course to create a running bond layout.
Step 9: Cutting Block
If the wall requires cutting block, try to cut square and straight using the one inch repeat on the block. Placing cut block at window and door locations will simplify the build.
Step 10: Leveling & Gluing
After two or three courses have been placed, shim and trim as needed so walls are level and plumb. Spot glue to footing or slab and wait for foam adhesive to set before continuing with your wall.
Step 11: Corner Offset
Flip corners each course to ensure the proper offset is maintained and vertical seams avoided.
Step 12: Working from Alignment System
Working off of the erected alignment system makes stacking the remaining block easy.
Step 13: Installing Alignment/Bracing
Using an approved alignment/ bracing system, such as BuildBrace 1, place as per O.S.H.A. recommendations. Windy locations may require placing the alignment system after the first or second course. Normally the 3rd or 4th course works best.
Step 14: Bucks Preparation
Window and door bucks should be made and ready to set in place as you are erecting the wall.
Step 15: Wood Buck Example
Here is an example of a window with wood bucking.
Step 16: Penetrations
Any penetrations must be made before the concrete is poured.
Step 17: Reinforcing Stagger
Place horizontal reinforcing as specified.
Note: the chase created to hold the vertical reinforcing in the proper location by staggering the horizontal reinforcing.
Step 18: Vertical Reinforcing Alignment
Place vertical reinforcing making sure to align it between the staggered horizontal reinforcing.
Phase 3: Pouring & Final Adjustment
After the wall is poured one person can use the adjustment on the top of the alignment system to ensure the wall is square and plumb.
Pouring in 4’ lifts, continue pouring until the concrete reaches the desired level. A low impact concrete vibrator with a 1” head is recommended to consolidate concrete during the pour.
When topping the wall leave extra concrete until all consolidation is completed. Place anchor bolts or straps when leveling the wall after consolidation. Time is of the essence, make sure you have time to finish, plumb and level wall before concrete sets.
Make sure top of wall is clean and flat. Wipe away debris and splatter. Once the final alignment is finished, stay off the alignment system to avoid possible movement of the wall. Sight wall after a half an hour, adjust wall as needed.
Learn more about building with icfs
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