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How does OpenStudio calculate floor U-values?

I have been looking at the Envelope Summary in the Energy Plus Results for some of my models of domestic buildings and found that the ground floor u-value is very high.

The construction is a simple 10mm of Ceramic Tile and 150mm of Concrete and I would have expected it to be far lower than this. How does OS calculate the U-value? Does OS take into account the exposed perimeter of the floor when calculating this? If so, is there a way of setting the exposed perimeter as my models have party walls with buildings that are not drawn in the model.

Thanks

image description

How does OpenStudio calculate floor U-values?

I have been looking at the Envelope Summary in the Energy Plus Results for some of my models of domestic buildings and found that the ground floor u-value is very high.

The construction is a simple 10mm of Ceramic Tile and 150mm of Concrete and I would have expected it to be far lower than this. How does OS calculate the U-value? Does OS take into account the exposed perimeter of the floor when calculating this? If so, is there a way of setting the exposed perimeter as my models have party walls with buildings that are not drawn in the model.

Thanks

image description

How does OpenStudio calculate floor U-values?

I have been looking at the Envelope Summary in the Energy Plus Results for some of my models of domestic buildings and found that the ground floor u-value is very high.

The construction is a simple 10mm of Ceramic Tile and 150mm of Concrete and I would have expected it to be far lower than this. How does OS calculate the U-value? Does OS take into account the exposed perimeter of the floor when calculating this? If so, is there a way of setting the exposed perimeter as my models have party walls with buildings that are not drawn in the model.

Thanks

image description

How does OpenStudio EnergyPlus calculate floor U-values?

I have been looking at the Envelope Summary in the Energy Plus Results for some of my models of domestic buildings and found that the ground floor u-value is very high.

The construction is a simple 10mm of Ceramic Tile and 150mm of Concrete and I would have expected it to be far lower than this. How does OS calculate the U-value? Does OS take into account the exposed perimeter of the floor when calculating this? If so, is there a way of setting the exposed perimeter as my models have party walls with buildings that are not drawn in the model.

Thanks

image description

I have calculated the solid floor U-value using the CIBSE Guide A method and found the U-value to be 1.625 W/m2K. Please see the methods and calculations below.

image description

image description (CIBSE Guide A)

image description (CIBSE Guide A)

How does EnergyPlus calculate floor U-values?

I have been looking at the Envelope Summary in the Energy Plus Results for some of my models of domestic buildings and found that the ground floor u-value is very high.

The construction is a simple 10mm of Ceramic Tile and 150mm of Concrete and I would have expected it to be far lower than this. How does OS calculate the U-value? Does OS take into account the exposed perimeter of the floor when calculating this? If so, is there a way of setting the exposed perimeter as my models have party walls with buildings that are not drawn in the model.

Thanks

image description Surface 29 is a simple solid floor made of: 10mm of ceramic floor tile with a thermal conductivity of 0.8 W/mK 150mm of concrete with a thermal conductivity of 1.7296 W/mK

I have calculated the solid floor U-value using the CIBSE Guide A method and found the U-value to be 1.625 W/m2K. Please see the methods and calculations below.

image description

image description (CIBSE Guide A)

image description (CIBSE Guide A)

How does EnergyPlus calculate floor U-values?

I have been looking at the Envelope Summary in the Energy Plus Results for some of my models of domestic buildings and found that the ground floor u-value is very high.

The construction is a simple 10mm of Ceramic Tile and 150mm of Concrete and I would have expected it to be far lower than this. How does OS calculate the U-value? Does OS take into account the exposed perimeter of the floor when calculating this? If so, is there a way of setting the exposed perimeter as my models have party walls with buildings that are not drawn in the model.

Thanks

image description Surface 29 is a simple solid floor made of: 10mm of ceramic floor tile with a thermal conductivity of 0.8 W/mK 150mm of concrete with a thermal conductivity of 1.7296 W/mK

I have calculated the solid floor U-value using the CIBSE Guide A method and found the U-value to be 1.625 W/m2K. Please see the methods and calculations below.

image description

image description (CIBSE Guide A)

image description (CIBSE Guide A)