CEFEP Technical Blog

Several EN and ISO standards offer detailed guidance on how to assess just how much additional energy is lost when flanges and other fittings are left uninsulated.

A single uninsulated flange can yield heat loss equivalent to between 3 and 5 m of insulated straight pipe.

EN ISO 12241:2008 suggests that, depending on the exact location, a single uninsulated flange can yield heat loss equivalent to between 3 and 5 m of insulated straight pipe. That’s an increase in energy loss of at least 300% and potentially as much as 500%.

These energy losses are so great that it’s not possible to "make-up" for them in any other way. Increasing the thickness of insulation applied to straight pipes or selecting insulation with lower thermal conductivity values will save only marginal amounts of energy when compared to the energy savings that can be realised by insulating all flanges, valves and pipe supports using FEF and PEF insulation.

Bridging the gap(s) made easy with flexible insulation

Bridging the gap(s) made easy with flexible insulation

An insulation system only can be as efficient as its weakest points, which makes insulating fixtures like flanges, pipe supports and bends essential. These pipework elements often feature diff icult geometry which is why flexible insulation materials that can be easily fabricated to fit should be the preferred choice for consultants and contractors.

FEF and PEF insulation materials are highly flexible. This makes it possible to insulate even the most complex pipework elements but they offer further, crucial, advantages too. These insulation materials can be easily cut to size on site without the need for specialist equipment – nothing else is needed other than a sharp knife. Since the materials are completely free from dust and fibres they are particularly easy and clean to work with, introducing no contaminants into the working environment.

The insulation of all parts of a pipe and duct system is easy to achieve with insulation products made of FEF and PEF. Due to their flexible, closed cell structure they can easily be cut to fit every part of the pipe system. Only if all parts of a pipe and duct system are insulated properly the mechanical building services can perform most efficiently. This is saving energy and reduces the risk of corrosion every day.

keep reading ...

Insulation of pipes and ducts is often an afterthought, seen as something that needs to be done but with little consideration given to the details of which materials or how they should be installed. This often leads to difficult or irregularly shaped parts of a pipe insulation system like flanges, valves, pipe supports and complicated bends or elbows being left un-insulated. In some cases these pipe fixtures are simply covered with PVC or duct tape to make them ‘look’ part of an insulated system without providing any of the energy saving benefits.

The FfE (Forschungsgesellschaft für Energiewirtschaft) in Munich conducted a study in 2012 to understand the impact of insufficient and incomplete (thermal) insulation on pipes and ducts. The institute examined the existing pipe insulation of six firms from different segments.

The findings are revealing: Retro-fitting all uninsulated components of the pipe systems could reduce energy losses by more than 20%(1).

Although the study is not representative of all building types, the results clearly demonstrate that applying thermal insulation to a pipe system in its entirety can have a significant impact when it comes to reducing the energy consumption and CO2-emssions of occupied buildings.

Source: (1) FfE Study - Energy saving potential by mechanical insulation, Final Report, November 2012 (only available in German)

keep reading ...

Keeping the surface of an insulation material above the dew-point temperature is key to stopping condensation.  Insulation thickness and thermal conductivity play major roles but, when it comes to controlling the surface temperature of insulation, no material property is more important than the surface emissivity.

Surface emissivity measures the potential of a material to emit energy in the form of thermal radiation.  Black, non-reflective, surfaces with a high emissivity finish are well suited to keeping the surface temperature above that of the dew-point.  Relatively small thicknesses of insulation can be used to reliably prevent condensation if the insulation material presents a high emissivity surface finish.

keep reading ...

Insulation made of flexible elastomeric foams (FEF) or polyethylene foams (PEF) can help to reduce the health risks associated with heating and plumbing pipework. Insulation is especially important when it comes to reducing bacterial growth inside domestic water supply pipes. "The Legionella bacteria grows at an accelerated rate in 'stationary' water at temperatures between 25 ºC and 60 ºC," explains Georg Eleftheriadis, Chairman of the European Association CEFEP.

"FEF or PEF thermal insulation can reduce temperature variations and so support the quality and 'purity' of drinking water.” Closed cell insulation with its in-built water vapour barrier saves energy efficiently and protects against moisture ingress at the same time.

International standards and strict EU regulations define how to supply drinking water in order to guarantee a high level of "purity". The European standard EN 806 defines precisely which measures should be implemented in order to supply safe, clean drinking water.

The legionella bacteria favours temperatures between 25 ºC and 60 ºC, a range that can be encountered in both hot and cold water pipes. When inhaled in small droplets - for example, as an aerosol in the shower - to the legionella bacteria can cause symptoms similar to those of pneumonia. "In order to counteract the risk of microbial contamination it is important that hot and cold water pipes are strictly isolated from each other by the appropriate technical insulation," explains Georg Eleftheriadis.

Reliable insulation protects against contamination

Appropriate pipe insulation helps to minimise the risk of hot water temperatures falling below 60 ºC and cold water temperatures increasing above 25 ºC. These are the safe water supply temperature limits defined within EN 806-2.

Alongside energy saving considerations, environmental factors like humidity, ambient temperature and pipe temperature will influence the pipe insulation thickness selected. Regardless of thickness, insulation should also be resistant to moisture ingress in order to ensure long term thermal performance.

This is where the advantages of FEF and PEF insulation are most obvious. For cold pipes the operating temperature is lower than the ambient air which leads to condensation. Using FEF or PEF insulation with an in-built water vapour barrier at the appropriate insulation thickness no condensation will form, either on the surface of the pipe or within the insulation itself.

keep reading ...

Mind the gap(s) to unleash additional saving potential

Energy losses from un-insulated fitting are so great that it’s not possible to “make-up for them in any other way.


Condensation Control

Learn more about how to prevent condensation forming on cold, 
refrigeration and air-conditioning pipes.

Subscribe to our newsletter

Once per month we send you an update of our latest post about the insulation of mechanical services