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DEWPOINT version 3.01 U-value calculation software for walls, roofs and floors - using the 'Combined Method' and condensation prediction based on BS EN ISO 13788:2012.
The program will now deal with 14 layers of construction including 3 thermally bridged layers.
25.00 (no VAT)
plus 25.00 annual licence charge after first year.
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This easy-to-use interactive u-value calculation software calculates the heat loss through the construction in accordance with BS EN ISO 6946:1997. It tests to see there is likely to be surface condensation, or interstitial condensation over a 12 month period, and if so, at which interfaces. It also checks to see if the monthly evaporation dries out any condensate remaining from previous months. The program now calculates the mass of walls as required by the new Part E - Resistance to the passage of sound. Solid floor and suspended floor calculations are in accordance with BS EN ISO 13370:1998

  • U-Value calculation uses the "combined method" for homogeneous and non-homogeneous layers as required by current UK legislation. The calculation allows for corrections for air gaps in insulation, and penetrating fastenings
  • Will calculate U-value for up to 14 layers including up to 3 thermally bridged layers
  • Surface and interstitial condensation calculation as BS 5250:2002 and BS EN ISO 13788:2012
  • Easy to add layer details, edit layers or insert new layers
  • Easy to do the corrections for air-gaps and fastenings
  • Easy to calculate warm roofs to BS EN ISO 13789
  • Easy to calculate basement walls
  • Easy to calculate air space resistances for high or low emissivity surfaces.
  • Easy to calculate under-floor resistance for suspended or solid floors as BS EN ISO 13370.
  • Select external temperature and relative humidity from 24 locations in UK, and other locations in France, Germany, Holland and Sweden. User can add more (in any country) if known.
  • User can select suitable method of establishing internal environmental conditions for the calculation.
  • Includes database of commonly used materials and allows for user defined materials
  • Shows and prints graph of vapour pressure at interfaces for all months of the year, illustrating which interfaces are at risk of condensation.
  • Shows amount of condensation or evaporation for each month of the year.
  • Prints detailed condensation report, and complete u-value calculation.

With the improvement in insulation levels, it becomes more and more important for designers to be aware if their chosen form of construction is likely to have a condensation problem at some times. Designers cannot afford to ignore the risks associated with surface or interstitial condensation.

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