Pouring concrete in more than one stage is possible. You can pour a second stage of concrete over the existing one or also pour another concrete surfacing stage over the new pour.
All you need to do is clean, create forms, prepare the concrete mix, pour the mix, level/finish, trowel, cure, and repeat.
This method of pouring concrete is known as “staging” and can be a great way to ensure the job gets done right.
Staging your pour allows you to spread out the work over several days, ensuring that each stage has been properly mixed and cured before moving on to the next steps.
Before beginning the pouring of the concrete task, you have to consider the project’s size, shape, finish, color, and complexity. Follow the process properly to install concrete in two stages and understand its nuances.
Let us start with the steps of pouring concrete in multiple stages.
How To Pour Concrete In Two Stages?
The process is simple once you have a clear idea regarding the first stage. You need to follow the same steps for all stages. Please remember, It should be done at least 24 to 48 hours after the curing once the first stage is completed.
Step 1: Clean The Surface
Before any construction work or concrete pour, the surface needs preparation to decrease the chance of getting heavy from frost or expansive soil. Utilize hand tools for small projects to clear the area of all rocks, grass, shrubs, old concrete, trees, and exposure to bare earth.
Heavy equipment speeds up the procedure, mainly when there is a large pour. Further, put and compact the sub-base or fill gravel till the soil is stable and compact.
Step 2: Create Forms
Once you prepare the sub-base, start setting the forms. Use wood forms with wood stakes or metal for your concrete residential tasks. Begin to attach the form to skates with any particular nail or screws in a way that you can remove it easily after curing concrete.
Ensure that forms are in good condition so that you can set them accurately for providing the proper slope or grade for drainage. Additionally, it can create clean corners wherever they meet, including different structures.
Step 3: Create a concrete bond
To create a successful concrete bond, you can choose between two options
- Use a commercial adhesive paint and apply it on the existing surface.
- Epoxy rebar into the existing concrete by drilling holes into the existing concrete and inserting the rebar with epoxy
Epoxy is, an adhesive material, used to attach steel rebar to any type of existing concrete.
Step 4: Mix Concrete
Mix the concrete with water as per the package instructions using the concrete bags. You can use a wheelbarrow and shovel for any small slab, but getting the concrete mixer can make the procedure easier for larger slabs.
Step 5: Pour Concrete Into Forms
Start pouring concrete into the forms fully up to the top edge. You should use shovels and rakes while pouring wet concrete to make the moving of concrete easy. Besides, make sure there are no air pockets or voids created during the pouring step.
Step 6: Smoothing And Leveling
You must use a large wood board or metal board for screeding the top surface of the concrete. It helps to consolidate and compact the concrete and start to level and smoothen the surface.
Next, take a float to further compact the concrete, even at high or low areas. It creates a smooth finish. Using small hand floats work great for edges and detail tasks, while large bull floats are excellent for working on larger areas.
Step 7: Begin Troweling
You need to observe two conditions and find out whether to start a trowel. If you find the rough broom finishing over the concrete surface, there is no requirement for extra finishing. If there is a smooth trowel or stamp over the concrete, there is a need for steel trowel finishing.
Allow the concrete to rest unless the surface starts to firm up. Once ready, take a steel trowel for smooth, complex, and uniform finishing. You can do troweling by skating on the surface on kneeboards, Trowell small areas, or with tools on long poles called funny trowels or Fresnos.
Step 8: Final Finishing
Once the troweling process, whether steel or float, is complete, start the final finishing to the surface. The most basic sort of finishing is called ‘broom finish.’ Experts pull special brooms across the concrete space generating a rough texture area.
Other sorts of finishes include texture, smooth trowel, or stamp, to name a few.
Step 9: Curing Concrete
Now is the time to rest and cure your concrete to make it hard and strong. Curing procedures usually last for 28 days, with the first 48 hours being the most critical. You can apply liquid chemical sealing and curing compounds to help cure concrete slowly and evenly. It helps to reduce curling, surface discoloration, and cracks.
Begin to use your concrete with light foot traffic after three to four days of placement. And you can start driving and parking on your surface after five to seven days of placement.
Next, repeat the process from the second step by creating the sub-base again (thick or thin according to your need).
You can skip the final finishing step in the first stage, as it will get hidden when you pour another layer of concrete. Thus, whether you are pouring concrete over the existing surface or the newly poured surface, you have to begin the entire procedure from step 2 mentioned above.
Note: If you want to multi-pour, you need to wait for 24 to 48 hours before curing completes.
For the majority of projects, pouring the concrete in two stages is a viable option. While it may seem intimidating, if you follow the steps and use the right material, it will save you time and money.
Make sure to adhere to safety protocols throughout the entire process. Don’t forget to wear protective gear when handling concrete. This will ensure your project can be done correctly with minimal disruptions.