Concrete is the world’s most popular building material by tonnage, making it the first choice for stability, adaptability, and strength. Concrete has been used for thousands of years to repel fire, burrowing animals, and centuries of weather abuse, from Rome’s Colosseum to nearly every pro sports arena in the United States.
Large footings are poured in place to provide stability in larger office buildings as well as large industrial, manufacturing, and commercial buildings. These concrete pilings can withstand an incredible amount of stress thanks to steel reinforcements and advanced engineering. The weight of these building blocks makes pouring in place more feasible.
However, there are numerous smaller applications where precast concrete pieces are far superior to pour in place. The cost of any construction project is always a consideration. However, it is critical to consider total costs, not just the base cost of materials or labor.
Of course, no two construction jobs are ever the same. Both cast in place concrete and precast concrete have enough similarities to be viable options. This is especially true for buried infrastructure, which necessitates the installation of manholes, utility vaults, catch basins, headwalls, and other concrete structures.
Large footings are poured in place to provide stability in larger office buildings as well as large industrial, manufacturing, and commercial buildings. These concrete pilings can withstand an incredible amount of stress thanks to steel reinforcements and advanced engineering. The weight of these building blocks makes pouring in place more feasible.
However, there are numerous smaller applications where precast concrete pieces are far superior to pour in place. The cost of any construction project is always a consideration. However, it is critical to consider total costs, not just the base cost of materials or labor.
Of course, no two construction jobs are ever the same. Both cast in place concrete and precast concrete have enough similarities to be viable options. This is especially true for buried infrastructure, which necessitates the installation of manholes, utility vaults, catch basins, headwalls, and other concrete structures.
Installation Periods
Whether you use on-site cast-in-place concrete or precast concrete products, the time spent on excavation at a job site will be roughly the same. Project managers may require a little more space for precast so that riggers can assist in setting the piece in place.
Setting up forms for pour-in-place will require less space in this regard, but the difference is negligible. However, once the excavation is completed, the time difference is astounding. Once the proper bedding is in place, precast concrete pieces can be immediately placed, connected, and backfilling can begin.
The forms must be set up and secured on-site, reinforcements (usually rebar) must be placed at proper intervals, and everything must be inspected for quality control. The integrity of the concrete may be compromised if the forms are not the correct width or the rebar is not properly spaced.
When working with concrete, the weather also plays a role. During a pour, too much rain or other precipitation could affect the ready mixed concrete. On windy days, debris may be blown into the forms in the same way. Although extreme temperatures are uncommon in this area, they may have an impact on the pouring and hardening phases of concrete.
That is not a concern with precast products, which can be delivered to the construction site at any time and in any weather. Catch basins or electrical vaults that have already been tested for strength at the facility can be installed 365 days a year, regardless of the weather. Even after being backfilled, these pieces continue to gain strength.
Backfilling cannot occur until the cast-in-place concrete has reached acceptable strength levels. This could have an impact on the construction schedule at the site depending on the season. It may take several days, if not weeks, for these concrete slabs to reach the optimal strength for backfilling.
During this time, excavation on the construction site must be secured to prevent accidents from workers and “civilians” who may be on site. Nothing has a greater impact on construction costs than days lost due to injuries or settling insurance claims due to unsafe working conditions.
As the concrete reaches the required strength, the forms can be removed and removed from the site, and finally, backfilling can begin. On large-scale projects, the time required to cast concrete in place is obviously factored into the schedule. Why would a construction manager not want to shorten the construction process?
Setting up forms for pour-in-place will require less space in this regard, but the difference is negligible. However, once the excavation is completed, the time difference is astounding. Once the proper bedding is in place, precast concrete pieces can be immediately placed, connected, and backfilling can begin.
The forms must be set up and secured on-site, reinforcements (usually rebar) must be placed at proper intervals, and everything must be inspected for quality control. The integrity of the concrete may be compromised if the forms are not the correct width or the rebar is not properly spaced.
When working with concrete, the weather also plays a role. During a pour, too much rain or other precipitation could affect the ready mixed concrete. On windy days, debris may be blown into the forms in the same way. Although extreme temperatures are uncommon in this area, they may have an impact on the pouring and hardening phases of concrete.
That is not a concern with precast products, which can be delivered to the construction site at any time and in any weather. Catch basins or electrical vaults that have already been tested for strength at the facility can be installed 365 days a year, regardless of the weather. Even after being backfilled, these pieces continue to gain strength.
Backfilling cannot occur until the cast-in-place concrete has reached acceptable strength levels. This could have an impact on the construction schedule at the site depending on the season. It may take several days, if not weeks, for these concrete slabs to reach the optimal strength for backfilling.
During this time, excavation on the construction site must be secured to prevent accidents from workers and “civilians” who may be on site. Nothing has a greater impact on construction costs than days lost due to injuries or settling insurance claims due to unsafe working conditions.
As the concrete reaches the required strength, the forms can be removed and removed from the site, and finally, backfilling can begin. On large-scale projects, the time required to cast concrete in place is obviously factored into the schedule. Why would a construction manager not want to shorten the construction process?
Adaptability and versatility
If you’ve ever worked with buried infrastructure, you’re aware of how many different-sized structures are sometimes required for a single project. Some products, such as vaults, have numerous applications, including wet and dry applications. Precast vaults are designed with multiple knockouts and strut channels for ease of use.
The same vault could be manufactured multiple times but used in various situations. By streamlining production, this improves turnaround times. Once the cast is in place, different forms must be created for each location. There is simply no way to improve the efficiency of pour in place concrete.
Cast in place and precast have both been used in the same product in some cases! Consider manholes, which are used as sewage and other wastewater system access points. Until recently, after installing manholes in the system, workers would be lowered into the structure and dig channels to improve flow.
That extra step is no longer required with the introduction of the Perfect Base. The Perfect Base is built to exact specifications, aligning the channels with existing or upcoming concrete pipelines. This is simply not possible when building the channels by hand in place.
The same vault could be manufactured multiple times but used in various situations. By streamlining production, this improves turnaround times. Once the cast is in place, different forms must be created for each location. There is simply no way to improve the efficiency of pour in place concrete.
Cast in place and precast have both been used in the same product in some cases! Consider manholes, which are used as sewage and other wastewater system access points. Until recently, after installing manholes in the system, workers would be lowered into the structure and dig channels to improve flow.
That extra step is no longer required with the introduction of the Perfect Base. The Perfect Base is built to exact specifications, aligning the channels with existing or upcoming concrete pipelines. This is simply not possible when building the channels by hand in place.
Is precast "greener" than cast-in-place concrete?
Concrete, regardless of production method, is a very environmentally friendly product. Concrete is chemically inert and free of Volatile Organic Compounds (VOCs) because it is made from naturally occurring raw materials. As a result, it is an excellent material for buried infrastructure.
Concrete is also a very strong material, designed to last for decades whether precast or poured in place. Because of their longevity, there is less need for replacement units and fewer repairs, resulting in a reduction in the demand for more concrete. It’s no surprise that this material has been so popular for so long!
Although it may be insignificant, precast facilities can reduce waste during production. Precast plants, because of their ability to trap and recycle wastewater and materials, send very little waste to landfills. That’s not to say cast-in-place concrete is wasteful; it’s just that concrete that overfills a form or dribbles on the ground during a pour cannot be reused.
Precast is also more durable than pour in place because the production process can be monitored at all stages. Any piece that leaves the facility has been tested for maximum strength. The same can be said for cast-in-place, but the conditions must be near-ideal.
In the end, precast concrete structures are just an overall better product. The one advantage cast in place has – initial cost – is easily offset by the consistent quality, installation ease, and installation speed. In the case of large building footings, cast in place just makes more sense. For smaller, more intricate products, precast can’t be matched.
Concrete is also a very strong material, designed to last for decades whether precast or poured in place. Because of their longevity, there is less need for replacement units and fewer repairs, resulting in a reduction in the demand for more concrete. It’s no surprise that this material has been so popular for so long!
Although it may be insignificant, precast facilities can reduce waste during production. Precast plants, because of their ability to trap and recycle wastewater and materials, send very little waste to landfills. That’s not to say cast-in-place concrete is wasteful; it’s just that concrete that overfills a form or dribbles on the ground during a pour cannot be reused.
Precast is also more durable than pour in place because the production process can be monitored at all stages. Any piece that leaves the facility has been tested for maximum strength. The same can be said for cast-in-place, but the conditions must be near-ideal.
In the end, precast concrete structures are just an overall better product. The one advantage cast in place has – initial cost – is easily offset by the consistent quality, installation ease, and installation speed. In the case of large building footings, cast in place just makes more sense. For smaller, more intricate products, precast can’t be matched.