Foamular-Metric 250 Thermal Resistance - R. Ratings.

The thermal resistance (R. rating) for Foamular-Metric 250 insulation is as follows:

• 25mm thickness ----- R .86
  
• 50mm thickness ----- R 1.7
  
• This is the R value of the product only. In building systems, various components all add to the total R value of the system.
  
• For example; in a brick veneer wall, bricks, timber, air space, plasterboard and internal and external air films all add to the total R value. With 50mm Foamular-Metric 250 this total R value will be approximately R 2.3.
  
• It should also be remembered that R values increase at lower temperatures.
  
• Because of its construction process, ie. extruded closed cell, there are no voids or air passages in Foamular-Metric 250. This means the R values are long term and consistent even in conditions subject to moisture.
  
• Advice on R values in various design situations such as roofing, cathedral ceilings, PRMA roofing, coolroom and cold store construction is available.
  
• Compared to normal polystyrene (eps, all grades), Foamular-Metric 250 extruded polystyrene has higher R values when installed and maintains this higher value as expanded polystyrenes degrade over time, losing their initial R value.