Substantially, floor radiant systems can be broken down into two categories: traditional systems and systems with low inertia or reduced thickness. This distinction is not based on any regulation but rather on operational and application experience. This article describes reduced-thickness radiant systems for new constructions and building upgrades.

Characteristics of reduced-thickness radiant systems

The main characteristics of reduced-thickness radiant systems include:

• Reduced thickness compared to traditional radiant systems when considering insulation + support layer + flooring 
• Low inertia and therefore higher speed in achieving the desired surface and set-point temperatures
• In specific applications, optional installation on existing floors as additional layer and with no need of invasive works
• Notes on inertia in radiant systemsIn physics, more specifically in mechanics, inertia is defined as the resistance of a physical object to any change in its velocity, and it is quantified by its inertial mass.

This represents a complex practice when applied to radiant systems as there are various thermodynamic conditions that must be considered when defining their performance. 

Factors affecting the inertia of the system: 

• Characteristics of the system (materials, thickness, thermal conductivity)
• Delivery temperature, flow rate and thermal difference
• Initial temperature 
• Temperature of the room to be air conditioned
• Location of the system (half-landing or facing the outside).

Dynamic simulations with finished elements on parts of the system represent a rapid and accurate assessment method.

On the contrary, when adopting an experimental approach based on the application for such analysis, we can no doubt state that a valid method may be to measure from cold the power released to the screed while monitoring the delivery and return temperature, the room temperature and of course a mean of the surface temperatures.

They feature the same volumes of standard manifolds and can be used for the same applications, but the patented bonnet installed in each circuit has multiple functions:

flow rate control: the bonnet cartridge membrane is engaged by the opening/closing of some circuits when the pressure varies. This changes its flow section and adjusts the flow rate to the set-up value, even with high differential pressures: operation up to 60 kPa for Low Flow versions; operation up to 150 kPa for High Flow versions;
flow rate presetting: the project max flow rate that must be kept constant can be set up for each circuit;

room temperature optimization: temperature control of the various rooms can be enhanced by combining the manifolds to thermo-electric actuators and room thermostats.

Various studies have been carried out to better quantify the energy saving enjoyed. Reference is specifically made to the study by Stefano P. CORGNATI, professor of Technical Physics of the Energy Department of the Politecnico of Turin: “ENERGY-SAVING POTENTIAL DERIVING FROM THE USE OF A MANIFOLD WITH FLOW-RATE DYNAMIC BALANCING”.

The study approach provides for design and development of an analytical-numerical model applied to two sample cases referred to as “individual” and “collective” model. The "individual" case reviews the typical situation of the actual effects occurring inside an individual housing unit, which may be a single-family home or an apartment with an independent heating system.

Conversely, the "collective" case reviews the typical situation of collective/multi-family residential buildings (condos, for example) with a centralized heating system where energy savings are linked to the energy consumption dynamics and behavior of the individual units.

Within the scope of this simulation model, the dynamic balancing proves to have a tangible impact in preventing overflows that induce overconsumptions, and by changing the perspective, this overconsumption corresponds to the ENERGY SAVING achievable through the use manifolds with “flow-rate dynamic balancing”.

With regards to the two cases examined and referring to calculation-related conditions (inputs and values typical of the model), we observed that:

the “individual” case, an example of energy saving in housing units with an independent heating system, showed energy savings up to 12%;
the “collective” case, an example of energy saving in multi-family buildings with a centralized heating system, showed energy savings up to 25%.

These are important numbers which confirm the perfect match between reduced-thickness radiant systems and balancing systems.

This coupling has proven to be solid not only from a theoretical standpoint, but also for their convenient application that makes these products easy to use, flexible and functional while offering key solutions to create radiant systems with high levels of energy saving ready to serve the market at best.

They feature the same volumes of standard manifolds and can be used for the same applications, but the patented bonnet installed in each circuit has multiple functions:

• flow rate control: the bonnet cartridge membrane is engaged by the opening/closing of some circuits when the pressure varies. This changes its flow section and adjusts the flow rate to the set-up value, even with high differential pressures: operation up to 60 kPa for Low Flow versions; operation up to 150 kPa for High Flow versions;
• flow rate presetting: the project max flow rate that must be kept constant can be set up for each circuit;

room temperature optimization: temperature control of the various rooms can be enhanced by combining the manifolds to thermo-electric actuators and room thermostats.

Various studies have been carried out to better quantify the energy saving enjoyed. Reference is specifically made to the study by Stefano P. CORGNATI, professor of Technical Physics of the Energy Department of the Politecnico of Turin: “ENERGY-SAVING POTENTIAL DERIVING FROM THE USE OF A MANIFOLD WITH FLOW-RATE DYNAMIC BALANCING”.

The study approach provides for design and development of an analytical-numerical model applied to two sample cases referred to as “individual” and “collective” model. The "individual" case reviews the typical situation of the actual effects occurring inside an individual housing unit, which may be a single-family home or an apartment with an independent heating system.

Conversely, the "collective" case reviews the typical situation of collective/multi-family residential buildings (condos, for example) with a centralized heating system where energy savings are linked to the energy consumption dynamics and behavior of the individual units.

Within the scope of this simulation model, the dynamic balancing proves to have a tangible impact in preventing overflows that induce overconsumptions, and by changing the perspective, this overconsumption corresponds to the ENERGY SAVING achievable through the use manifolds with “flow-rate dynamic balancing”.

With regards to the two cases examined and referring to calculation-related conditions (inputs and values typical of the model), we observed that:

• the “individual” case, an example of energy saving in housing units with an independent heating system, showed energy savings up to 12%;
• the “collective” case, an example of energy saving in multi-family buildings with a centralized heating system, showed energy savings up to 25%.

These are important numbers which confirm the perfect match between reduced-thickness radiant systems and balancing systems.

This coupling has proven to be solid not only from a theoretical standpoint, but also for their convenient application that makes these products easy to use, flexible and functional while offering key solutions to create radiant systems with high levels of energy saving ready to serve the market at best.