New pipe insulation app launched

The new Pipe Insulation Tool is a free, easy-to-use app for designers, installers and property owners to assess the effectiveness of insulation in delaying the freezing of water in pipes. Inputting a few key pieces of information will reveal how many hours protection you can expect from the insulation. By varying material thickness or type, you can calculate how much insulation is required for a given set of freezing conditions, aiming to get at least 12 hours protection as the answer at the bottom of the calculation sheet. This assumes that warmer conditions return within 12 hours to prevent freezing, for example by the premises being re-occupied and the consequent demand for water reintroducing flow in the pipes.

While the indicator is set for 12 hours, users can still use the tool for situations where greater protection is needed, such as where there will be no water demand for periods greater than 12 hours, or where there is not likely to be a positive change to the surrounding conditions after 12 hours (i.e. increase in the ambient temperature). However users will need to decide the appropriate “total hours” protection needed.

To use the tool, you will need to know:

  • the pipe’s diameter inside and out and its material;
  • the expected water supply temperature;
  • the air temperature in the immediate surroundings of the pipe;
  • the thickness of the insulation material and;
  • the thermal conductivity of the chosen insulation.

The temperature of water coming into properties from the water mains can be influenced by the time of year and water source (i.e. rivers, reservoirs, underground boreholes or wells). Where temperature information isn’t readily available, a water temperature value of 2oC should be used as the lowest winter-time value.

Thermal conductivity is the rate at which heat passes through a material (expressed as W/mK). Details for insulation materials are available from the supplier or manufacturer of the insulation.

How to get the Pipe Insulation Tool

The Pipe Insulation Tool is free to use from the WRAS website and will work direct  in the user’s web browser:


How to use the tool is explained in our user guide:


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