Use this Nine Step Guide to help increase your knowledge and to have a better understanding of what takes place before, during and after concrete placement in residential and commercial concrete installations.
Step 1 – The Sale
Once your decision has been made, the contract has been signed between the professional concrete contractor and the customer, and the payment arrangements have been made; then the real work can begin to install concrete for your patio, garage floor, concrete slab, sidewalk, driveway and/or front steps.
Step 2 – Site Work
Before concrete can be placed, the site needs to be prepared. The area needs to be cleared and/or cleaned. Most often earth moving equipment is used to clear the area to speed the process. All grass, rocks, trees, shrubs, and old concrete needs to be removed, exposing raw earth. It is recommended that you have sub-base of a minimum (4-6) inches of granular fill , unless the soil is very compact and stable. The sub-base fill is then placed and compacted over the entire area where concrete will be placed. Proper sub-base preparation is important to allow the concrete to cure properly.
Step 3 – Forming
Once the sub-base is prepared, forms can be set. Concrete forms are made from wood, metal or plastic, and can range in height from 4 inches to many feet. For most residential and commercial concrete projects, wood forms will be used. Forms should be set to provide the proper slope or grade for drainage, and that form clean corners where they meet each other or other structures.
Step 4 – Placement
The sub-base is now compacted and the forms are set. Now it’s time for the concrete. SRS Construction will then order a concrete mix that meets the requirements for the specific concrete project, whether it is for patio, garage floor, concrete slab, sidewalk, and driveway or front steps being placed. If you live in a freeze thaw climate, a minimum of 4% of air, small stone can be used as aggregate in the concrete if it is going to be stamped vs. regular 3/4 inch stone for broom or smooth finish concrete slabs.
Step 5 – Leveling Concrete
Once the wet concrete has been placed into the forms, a large metal or wood board is used to screed (leveling with a straight edge using a back and forth motion while moving across the surface) the top of the concrete. This screeding process helps compact and consolidate the concrete, and begins the smoothing and leveling of the top of the concrete.
Once the surface has been screeded, the concrete is “floated”. This involves using a special trowel called a float. The surface is floated to further compact the concrete, even out any depressions or high areas, and create a smooth finish on the surface.
Step 6 – Troweling
A rough broom finish concrete surface does not require any additional finishing after the floating procedure. For a smooth troweled or stamped finish, a steel trowel is needed. The concrete will be left to rest until the surface begins to firm up. Once firm, steel troweling is performed to create a smooth, hard and uniform finish across the concrete surface.
Step 7 – Finish
Once all the troweling (float or steel) is complete, the final finish can be applied to the concrete. The most basic type of finish is known as a “broom finish”. A special broom is pulled across the concrete surface creating a rough textured surface.
Step 8 – Curing
Once all the placement and finishing is complete, the concrete can rest and begin to cure (get hard). The curing process lasts 28 days, with the first 48 hours being the most critical. It is recommended that a liquid chemical curing and sealing compound be applied to the concrete as soon as the finishing process is complete. The curing compound helps the concrete cure slowly and evenly, which helps reduce cracks, curling, and surface discoloration.
If concrete is placed in weather below 40F, curing blankets should be used to keep the concrete warm during the initial few days of the curing process. The colder the temperature, the longer it will take concrete to cure. You can start to use your concrete for light foot traffic 3 to 4 days after placement, and you can drive and park on your concrete 5 to 7 days after placement.
Step 9 – Maintenance
Concrete is a durable product, and if placed, finished and cured properly, it should last a lifetime. While concrete is often viewed as a no maintenance product, consider the following simple maintenance procedures to increase the service life of your concrete. A good quality sealer is always a good idea. A cure and seal may be used the same day the concrete is placed, or a high quality sealer may be applied a month after the concrete is placed.
Exterior concrete sealers can last anywhere from 1 to 5 years, depending primarily on environmental conditions. Occasional soap and water cleaning is also advised to keep your concrete looking its best. Sealing and regular maintenance will also minimize the chances from staining and discoloration caused by natural or man-made contamination.
Concrete has been around for thousands of years and remains the most popular choice for residential patios, walkways, and driveways. When you make the decision to go concrete, understanding the basic steps will make the entire process run smoother for all parties involved.
When installed properly, concrete is one of the most durable and long lasting products you can use around your home. But it is important that concrete contractors follow well-established guidelines with respect to concrete placement. Durable, high strength and crack resistant concrete does not happen by accident.
This is one video made by SRS Construction on concrete finishing…