Activation of the concrete core

Thermally Active Building Systems Explained

When it comes to controlling the indoor temperatures of complex environments such as modern buildings, innovative solutions are required. HVAC systems are relatively climate sensitive, and so the need for modern temperature regulation systems to function reliably in all climates becomes greater.

That’s why there is an increasing trend in 21st-century green building design to move away from conventional all-air systems as the primary method of temperature control, and integrate them with TABS – thermally active building systems.

The reason for the upsurgence of TABS as a priority green design element in modern commercial construction is a simple two-fold one: they are far more cost-effective and energy-efficient than their counterpart systems. That alone should be reason enough to consider them for any and all building projects you plan to undertake. However, a slightly more in-depth explanation may be what you require to make informed project planning decisions.

How Do Thermally Active Building Systems Work?

A fundamental concept to understand about thermo-active building systems is that they make use of the existing thermal capacity of the building, rather than requiring any additional occupational space for the installation of a conventional HVAC system such as pipes for central air-conditioning. In modern multistory buildings, this would be the space between the concrete floors and ceilings of the structure.

diagram showing the thermal coupling of radiant cooling system pipes and existing building concrete mass

Principally, thermo-active systems work by activating the mass of the building and employing the inherent heating and cooling characteristics of the building material to facilitate the process of temperature control. In radiant cooling systems, this would be done through a relationship known as thermal coupling – using water flow to influence the temperature of the concrete and thereby active the transfer of energy. Why is this so powerful and efficient? Because it takes away the strained need to individually regulate room temperatures with vastly different load requirements and instead uses the mass of the entire building to regulate temperature like a functioning organism.

How Do Thermally Active Building Systems Use Less Energy?

The physical properties of water allow radiant cooling solutions to remove a proportionate amount of thermal energy using less than 5% of the energy that a fan in a conventional HVAC system would use. Water has a much greater density than air, as can be seen in the diagram below, which in essence means that energy transfer within buildings can take place at greater efficiency using considerably less space – making radiant cooling systems possible for commercial application.

It would then be naturally acceptable to allocate a given amount of the 95% reduction in energy to run conventional HVAC systems concurrently with TABS – at a vastly reduced capacity to facilitate the search for optimal temperature in every indoor environment.
how do thermally active building systems use less energy

How Do Thermally Active Building Systems Save Costs?

Because water can hold a greater amount of energy per given unit than air, it therefore requires a relatively less amount of energy to pump that same amount of energy through water. In this way, operating costs of radiant cooling systems are greatly reduced when compared to conventional HVAC systems, particularly on an industrial scale. Radiant cooling systems are also maintenance free after installation, making the plausibility of an optimal relationship between an air and water system a reality, while still allowing for greatly reduced maintenance costs.

The highlighted considerations make a strong case for thermo-active building systems to be incorporated as beneficial elements to your building’s green design objectives and certainly to carry it into the future as a cost and energy saving entity.

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