Insights | 19th Jul 2023
How to Complete a Perfect Concrete Pour
5 Tips for Cast In Place Concrete with Haselden’s Senior Superintendent Scott McClain
Parking garages are crucial to a campus or community, yet they should blend into the background with seamless function and high-quality construction. Utilizing the cast-in-place method, they can be built to last decades. Avoid common pitfalls that can lead to structural failure or unsightly errors with these five tips:
1. Plan Thoroughly Before Construction Starts
Although concrete structures can be constructed quickly, you can’t undo issues after a pour. In a parking garage, MEP (mechanical, electrical, and plumbing) systems require intense coordination to ensure that everything will function correctly in the final structure. Sleeves for plumbing lines, fire sprinkler pipes, mechanical ductwork, and electrical need to be under a certain diameter so they don’t intersect with post-tension cables, rebar, and other embedded items through the structure. If not, the structure will be compromised in the final tightening of the post-tension cables. All these sleeves need to be coordinated with the structural engineer. Then, the design is incorporated into a Building Information Model (BIM) for all the subcontractors to use to ensure all the height restrictions, sleeves, and clearances are met and achieved for a complete and functional product.
During this stage, meet with the structural engineer and subcontractors to review the post-tension drawings. This ensures everyone is on the same page before any work is done. It is also a great time to coordinate manpower to help all teams stay on schedule. Because of the amount of work that needs to be done before a concrete pour, one minor setback can delay the entire project.
To ensure accuracy on the project, we develop a detailed concrete pre-pour checklist. This checklist is completed collaboratively with all subcontractors that have work within a concrete pour, and successful completion of the checklist ensures all subcontractors have installed their work correctly.
2. Pay Close Attention to Grading and Drainage:
Sitework is key to every job, but especially to parking garages. Water should always drain away from the structure, or to designated drains within the garage. If these aren’t performed correctly, it can present a danger to drivers with slick patches or even structural problems from ice and water damage. We work closely with the architect to measure the grades correctly and ensure they are accurate before pouring a single yard of concrete.
3. Sequence Is Paramount
Since parking garages are usually nestled in a vacant space on campus or tight to existing buildings, the order we pour is crucial to keeping the site as functional as possible and safeguarding pedestrians. We sequence the pours going from the tightest space out to the easiest accessible side. This minimizes disruptions to the natural flow of a site as well as road closures for concrete trucks. Pouring towards the tightest area of the site risks disrupting the pedestrian and traffic flow, damaging our existing structures, and making errors in the final pour.
It is essential for the flow of the project that all subcontractors’ work is coordinated so that concrete pours adhere to the pour schedule, achieving adequate cure times without delaying the work on subsequent levels.
4. Coordination is Critical
With advances in parking garage management using devices such as License Plate Recognition Systems (LPR), parking vacancy detection, payment kiosks, video intercoms and security cameras, early equipment selection and design is required to ensure the proper infrastructure and device locations are coordinated and installed prior to concrete being poured.
No less important is the focus on the future sustainability of a parking garage. If a green roof or photovoltaic panels, for example, are not in your current budget, installing structural components or the additional infrastructure necessary to accommodate these future needs during initial construction of your garage allows you to modify your garage in the future while saving time, reducing costs, and reducing downtime of your garage when these improvements are made.
5. Keep the Site Clean
For a perfect final finish, the forms for the concrete must be free of any trash – even small construction debris. While a clean site should be a given, due to the nature of the forms and their construction, it leaves gaps for construction materials such as nails or wood shavings to fall through the cracks unnoticed and ultimately show through once the forms are removed. Before any pour, inspect the forms for a final time to remove any unwanted material.
With an experienced team, your next parking garage can strike both form and function. The right team will be able to guide you through the process, delivering a seamless and efficient project. If you are considering a project or want to learn more about our approach to cast-in-place concrete, please reach out.