BuildBlock ICF Installer Training Series: Pre-Pour Inspection
Welcome to the BuildBlock ICF Installer Training Series: Pre-Pour Inspection. This 20 part video series is intended to be an educational walk through of the ICF building process. From the early planning phases to pouring concrete and finishing walls, this series will provide the basic knowledge you need to have a successful BuildBlock ICF build.
In video number 13 we cover how to inspect an ICF project for common mistakes that cause problems during the pour, while finishing, or during occupation.
The videos in this series are produced as a companion to the BuildBlock Installation and Technical Manuals available for free download on the Publications Page or for purchase via the BuildBlock Online Store. You can view more videos in this series via the BuildBlock Blog or by subscribing to the BuildBlock YouTube Page. For a more in depth training experience you can take the free Online ICF Installer Training Series.
Pre Pour Inspection
In this video we will cover how to inspect an ICF project for common mistakes that cause problems during the pour, while finishing, or during occupation.
Ensure footings are correctly laid out, leveled, and formed properly based on prescriptive or site specific engineering and local codes. Verify sufficient rebar is correctly placed in footings before they are poured.
After forming footings, a footing inspection may be required before they are poured.
Also verify that all vertical dowels are correctly placed with sufficient height above the footing (typically 24”) to correctly lap vertical rebar in the walls and have a minimum clearance from the soil of 3 inches.
Make sure that the walls match the layout marked on the footing before the wall is stacked and double check that the walls meet specified dimensions and that the structure is square.
Walk and Check
Take a walk around the jobsite to confirm that you are ready to pour. Make sure that there is easy access for ready mix trucks, pump trucks, and line pumps. Ensure that the pump truck has ample time to set up before the concrete arrives and determine a wash out location for your ready mix trucks and pumpers.
Verify that the jobsite is clean and remove any debris or obstacles that could get in the way during the pour.
Check to make sure team members are ready for the pour and have what they need. Ensure that the proper tools are in place for the pour including additional strapping material such as wood, and other materials in case any problems arise. Recheck the walk boards and scaffolding for security, stability and safety. Check the plumb of all walls and corners. Square and level all doors and windows and check that all of the strapping and supports are in place.
While walking around the site, take special note of rebar. Verify the placement of vertical dowels. Check that all vertical reinforcement lines up with the footing dowels and stays within lap specifications. Horizontal rebar should be alternated either side of center (or tension side of the wall below grade) to create a vertical chase to hold the vertical rebar in place. Tie the top of the vertical rebar to the top horizontal rebar. Check the tops of openings for proper placement of lintel steel and ensure proper reinforcement below openings.
Mark the location where anchor bolts will be placed on the top course and check to make sure that anchor bolts are on site and the correct length. Ensure that the embedded length meets code requirements or site specific engineering and the threaded end of the J-bolt extends high enough above the top plate to tighten bolts. If desired, trim off block interlock for a smooth top plate surface to screed to. When trimming the interlock or making other cuts, be cautious not to let any waste fall into the cavity wall. Before pouring clear any waste and debris from the wall cavity.
Verify that all common or vertical seams are strapped appropriately inside and out. Make sure that openings are properly bucked, braced, and strapped. Check that all beam pockets, weld plates, floor system hangers, penetrations, or knockouts are in place and strapped. Lastly, check potential problem areas such as openings near corners or vertical joints and make sure that they are strapped appropriately.
Before pouring, ensure that the wall is adequately braced, especially at each corner. Double check the foot brackets and add additional stakes if necessary. Make sure that the adjustment on all bracing works and check that the screw attaching bracing to the wall is at the top of the slot and just snug enough to allow a small amount of settling during the pour. Make sure the wall is both level and plumb.
If bracing a basement, walls may be very slightly adjusted to the inside. This makes it easier to push a wall out during alignment. Keep in mind that alignment must be done every lift and that all corners must be kept plumb at all times. Install a string line for straightening the wall after the pour.
Inspect all opening supports and make sure that openings have access holes on the bottom. This will allow you to inspect and ensure proper concrete consolidation. Double check that all openings are square and use adhesive foam to fill in any areas that may leak concrete.
Penetrations, Knockouts, and Hangers
Verify that all penetrations are in the proper place and that sleeves are secured. If penetrations cut through webs or compromise the structural integrity of the block, make sure to add extra support. Take a look at all joist hangers, inside and out, to ensure that they are installed at correct locations, are stable, and firmly secured. Finally, check any brick ledge forms for reinforcement as well as all other bracing, stirrups, and reinforcement.
Check the order
Take a final look at your concrete order and make sure that the correct amount and proper mix were ordered. It is often advisable to let the mix plant know that it is an ICF pour and that you will be testing slump for each pour.
Slump concrete for each truck as it arrives to prevent problems by verifying the mix. Typical mix is 3,000 PSI concrete with 3/8ths inch chip mix at a 5 ½ to 6 inch slump out of the pump. A concrete mix that is too wet will cause too much pressure on the ICF forms. A mix that is too dry will not pump or consolidate properly.
Lastly, communicate with your team to ensure that every person involved in the pour understands the plan and how to identify problems. Make sure that everyone is equipped with the required personal protective equipment.
Divvy up jobs such as pumping, vibrating, aligning, finishing, and inspecting and make sure that every person knows their job and expectations.
For more information review the BuildBlock Installation & Technical Manual and visit buildblock.com