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As construction changes, so does concrete. On the jobsite, specialty contractors recognize the unique demands of concrete when it comes to planning, logistics and pouring. By keeping pace with new developments while following the fundamentals of interacting with concrete, MEP contractors can manage their own jobs efficiently and cost-effectively. 

This article explores innovations in concrete currently or soon to be impacting jobsites, and the keys to successfully coordinating MEP tasks with the time-sensitive art of concrete pouring.

Innovations in Concrete

Concrete comes in many forms, designed for everything from underwater bridge pillars to the tallest buildings in the world.

As one of the oldest building materials known to humankind, concrete’s advantages include durability, strength and low maintenance requirements.

Today, a range of innovations are shaving away at its widely acknowledged disadvantages, including excess emissions in manufacturing, hefty weight in shipping and added costs and time on the jobsite.

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  Eco Concrete

  Today’s eco concretes lessen their environmental impact by incorporating recycled materials such as biochar or repurposing the fly ash captured from coal-burning power plants.

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  Bendable Concrete

  In use on bridges and skyscrapers, “bendable” concrete — or Engineered Cementitious Concrete (ECC) — incorporates silica sand to generate a hard but flexible concrete that’s better at enduring harsh climate conditions.

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  Porous Concrete

  Also known as pervious concrete, porous concrete is increasingly popular in urban centers, where stormwater runoff continues to overwhelm aging municipal water systems and create flooding.

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  Precast Concrete

  BIM and precision modeling now enable coordination that adds certainty to planning and coordinating for precast concrete elements.

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  3D Concrete Pours

  Now in use in residential and proof-of-concept construction, 3D concrete pours have yet to become mainstream while costs are high and quality is sketchy. As with any technology, beta testing will continue to push the boundaries of reliability, economic feasibility and scalability.

Challenges of Concrete Planning and Pouring

Every grade and type of concrete relies on chemical reactions to establish its compressive strength and durability. If a load of concrete is allowed to languish, it will set and become an expensive, useless rock.

For that reason, concrete takes critical-path precedence on jobsites. Other trades don’t necessarily come to a halt, but they yield if they must. In fact, impending set times explain why drivers typically carry cure retarders — and at one time, bags of sugar — in case of a delivery delay. They stand ready to slow or sacrifice the load’s viability rather than letting it harden and destroy the truck.

When the clock is ticking, the logistics of concrete ripple into every aspect of the jobsite. Concrete pours demand a highly intricate choreography, especially in heavy civil construction and other jobs consuming immense quantities.

During any pour, the concrete company might be juggling multiple jobs, dispatching trucks and assigning crews for just-in-time delivery. At the same time, third-party inspectors could be dispatched onsite to test for qualities such as flow consistency.

On-site, extensive prep work includes more than installing rebar and erecting forms. Site conditions must also be addressed and stabilized, with assessments on questions such as the need to dewater or to remove or infill soil.

The MEP x Concrete Connection

Long before trucks roll onto the jobsite, coordination and planning set the stage for seamless collaboration among MEP trades and concrete contractors. To avoid the error-prone and costly practice of cutting and boring set or cured concrete, concrete is increasingly being framed out for penetrations before the pour.

In these cases, the designers might prepare plans for concrete contractors to follow, or GCs will lead MEP and concrete teams in collaborating to plan and frame out the penetrations.

Framing out beforehand adds time to the concrete pour, but it also allows the trades that follow to move more swiftly. Especially in urban settings, preplanning mitigates risk by keeping the number of people and machinery onsite to the minimum needed to integrate MEP systems with concrete.

The demands of the schedule, the job and the availability of labor can dictate whether GCs and their specialty contractors can plan in advance. Framing out is also trickier for the vertical pours impacted by gravity than the simpler horizontal pours.

The immutability of concrete makes it a strong candidate for preventing rework through advance alignment of tolerances and specs. For example, air handling units, boilers and other MEP equipment often sit on concrete pads built to accommodate their specifications.

That’s when it’s important that the MEP, concrete and general contractors collaborate to guarantee adherence to scope and proper preparation of the concrete pad.

Preplanning can also facilitate coordination of first-floor or basement slab pours, when MEP contractors have the chance to embed their pipes, conduits or sleeves on rebar cages before pouring starts.

Embedding is an efficient technique for projects like multifamily housing where every kitchen has an island connected to water and power. The GC must take care to account for underground installation of all the trades, but when embeds are possible, they save time in logistics, coordination and execution.

Safety elements can also be embedded into concrete, such as tie-off points on high-rise projects or I-beams for holding bolts. Advance coordination enables strategic spacing and placement, to mitigate risk by making critical safety elements accessible at key points.

Concrete Is Universal

In construction, concrete is universal. Like the MEP trades, the work of concrete logistics, planning and installation is performed by specialists, skilled in delivering high-quality results while mitigating risk and creating operational efficiencies.

And it’s all performed under high-pressure timelines, because concrete won’t wait. Focused coordination among concrete contractors and the MEP trades prepares jobs for smoother implementation and optimal outcomes.

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