R-value - Revision history

Editor at 13:45, 3 September 2020

2020-09-03T13:45:52Z

← Older revision		Revision as of 13:45, 3 September 2020
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	* Transparent insulation.		* Transparent insulation.
	* U-value.		* U-value.
		+	* U-What?

−	[[Category:~~Definitions~~]] [[Category:~~DCN_Definition~~]] [[Category:~~Standards_/_measurements~~]] [[Category:~~DCN_Standard~~]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:Definitions]] [[Category:Standards_/_measurements]]

Designing Buildings at 07:54, 1 March 2020

2020-03-01T07:54:14Z

← Older revision		Revision as of 07:54, 1 March 2020
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	= Indoor air quality =		= Indoor air quality =

−	R-value is the: 'Sum of all Ri values. Ri is the ratio Ci or LCIi, where Ci is the mass concentration of the individual VOC i. in the air of the reference room, and LCIi is the LCI value of VOC i. The LCI value is the ‘Lowest Concentration of Interest’, which is the substance-specific value for health-related evaluation of the emission from construction products as agreed by the EU-LCI Working Group (https://ec.europa.eu/growth/sectors/construction/eu-lci_en).'	+	R-value is the: 'Sum of all Ri values. Ri is the ratio Ci or LCIi, where Ci is the mass concentration of the individual VOC i. in the air of the reference room, and LCIi is the LCI value of VOC i. The LCI value is the ‘Lowest Concentration of Interest’, which is the substance-specific value for health-related evaluation of the emission from construction products as agreed by the EU-LCI Working Group [https://ec.europa.eu/growth/sectors/construction/eu-lci_en https://ec.europa.eu/growth/sectors/construction/eu-lci_en].'

	Ref [https://www.breeam.com/NC2018/ BREEAM UK New Construction, Non-domestic Buildings (United Kingdom), Technical Manual, SD5078: BREEAM UK New Construction 2018 3.0], published by BRE Global Limited		Ref [https://www.breeam.com/NC2018/ BREEAM UK New Construction, Non-domestic Buildings (United Kingdom), Technical Manual, SD5078: BREEAM UK New Construction 2018 3.0], published by BRE Global Limited
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	* U-value.		* U-value.

−	[[Category:Definitions]] [[Category:Standards_/_measurements]]	+	[[Category:Definitions]] [[Category:DCN_Definition]] [[Category:Standards_/_measurements]] [[Category:DCN_Standard]]

Designing Buildings at 07:53, 1 March 2020

2020-03-01T07:53:11Z

← Older revision		Revision as of 07:53, 1 March 2020
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		+	= Introduction =
		+
		+	R-values can refer to:
		+
		+	* Thermal resistance.
		+	* Indoor air quality.
		+
		+	= Thermal resistance =

	R-values are a measure of the thermal resistance of a material of a specific thickness, that is, its resistance to the transfer of heat across it. The higher the R-value of a material, the more effective it is as an insulator.		R-values are a measure of the thermal resistance of a material of a specific thickness, that is, its resistance to the transfer of heat across it. The higher the R-value of a material, the more effective it is as an insulator.

−	R-values can be used as part of a labelling system to enable comparison of the thermal performance of different materials, such as insulation, or as part of the calculation of heat transfer across the fabric of a building.~~<br/>~~	+	R-values can be used as part of a labelling system to enable comparison of the thermal performance of different materials, such as insulation, or as part of the calculation of heat transfer across the fabric of a building.

−	R-values can be calculated by dividing the thickness of a material (in metres) by its thermal conductivity (k-value or lambda value (λ) in W/mK). R-values are therefore expressed in m2K/W (or ft2·°F·hr/Btu in the USA). The overall R-value of a multi-layered element can be calculated by adding the R-values of its component materials.~~<br/>~~	+	R-values can be calculated by dividing the thickness of a material (in metres) by its thermal conductivity (k-value or lambda value (λ) in W/mK). R-values are therefore expressed in m2K/W (or ft2·°F·hr/Btu in the USA). The overall R-value of a multi-layered element can be calculated by adding the R-values of its component materials.

	R-values are sometimes described as being the reciprocal of U-values (sometimes referred to as heat transfer coefficients) which describe the thermal conductivity of a building element. However, unlike U-values, R-values do not include surface heat transfers at the boundary of the element by convection and radiation.		R-values are sometimes described as being the reciprocal of U-values (sometimes referred to as heat transfer coefficients) which describe the thermal conductivity of a building element. However, unlike U-values, R-values do not include surface heat transfers at the boundary of the element by convection and radiation.
Line 10:		Line 18:
	U-value = 1 / (the sum of the R-values of the layers of the element + the resistance of the internal and external surfaces of the element)		U-value = 1 / (the sum of the R-values of the layers of the element + the resistance of the internal and external surfaces of the element)

−	= ~~Find out more~~ =	+	= Indoor air quality =
		+
		+	R-value is the: 'Sum of all Ri values. Ri is the ratio Ci or LCIi, where Ci is the mass concentration of the individual VOC i. in the air of the reference room, and LCIi is the LCI value of VOC i. The LCI value is the ‘Lowest Concentration of Interest’, which is the substance-specific value for health-related evaluation of the emission from construction products as agreed by the EU-LCI Working Group (https://ec.europa.eu/growth/sectors/construction/eu-lci_en).'
		+
		+	Ref [https://www.breeam.com/NC2018/ BREEAM UK New Construction, Non-domestic Buildings (United Kingdom), Technical Manual, SD5078: BREEAM UK New Construction 2018 3.0], published by BRE Global Limited
		+
		+	= Related articles on Designing Buildings Wiki =

−	~~=== Related articles on Designing Buildings Wiki ===~~	+	* Aerogel insulation for buildings
−	*Aerogel insulation for buildings	+	* g-value.
−	*g-value.	+	* k-value.
−	*k-value.	+	* Insulation.
−	*Insulation.	+	* Phase change materials.
−	*Phase change materials.	+	* Shading coefficient.
−	*Shading coefficient.	+	* Solar heat gain coefficient.
−	*Solar heat gain coefficient.	+	* Thermal bridge.
−	*Thermal bridge.	+	* Transparent insulation.
−	*Transparent insulation.	+	* U-value.
−	*U-value.	+

−	[[Category:Standards_/_measurements]]	+	[[Category:Definitions]] [[Category:Standards_/_measurements]]

Designing Buildings: Reverted edits by 195.195.140.13 (talk) to last revision by Designing Buildings

2017-03-23T17:47:43Z

Reverted edits by 195.195.140.13 (talk) to last revision by Designing Buildings

← Older revision		Revision as of 17:47, 23 March 2017
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−	~~I beat my meat to the sound of the beat~~

−	~~=== Related articles on Designing Buildings Wiki ===~~	+	R-values are a measure of the thermal resistance of a material of a specific thickness, that is, its resistance to the transfer of heat across it. The higher the R-value of a material, the more effective it is as an insulator.

−	* Aerogel insulation for buildings	+	R-values can be used as part of a labelling system to enable comparison of the thermal performance of different materials, such as insulation, or as part of the calculation of heat transfer across the fabric of a building.<br/>
−	* g-value.	+
−	* k-value.	+	R-values can be calculated by dividing the thickness of a material (in metres) by its thermal conductivity (k-value or lambda value (λ) in W/mK). R-values are therefore expressed in m2K/W (or ft2·°F·hr/Btu in the USA). The overall R-value of a multi-layered element can be calculated by adding the R-values of its component materials.<br/>
−	* Insulation.	+
−	* Phase change materials.	+	R-values are sometimes described as being the reciprocal of U-values (sometimes referred to as heat transfer coefficients) which describe the thermal conductivity of a building element. However, unlike U-values, R-values do not include surface heat transfers at the boundary of the element by convection and radiation.
−	* Shading coefficient.	+
−	* Solar heat gain coefficient.	+	U-value = 1 / (the sum of the R-values of the layers of the element + the resistance of the internal and external surfaces of the element)
−	* Thermal bridge.	+
−	* Transparent insulation.	+	= Find out more =
−	* U-value.	+
		+	=== Related articles on Designing Buildings Wiki ===
		+	*Aerogel insulation for buildings
		+	*g-value.
		+	*k-value.
		+	*Insulation.
		+	*Phase change materials.
		+	*Shading coefficient.
		+	*Solar heat gain coefficient.
		+	*Thermal bridge.
		+	*Transparent insulation.
		+	*U-value.

	[[Category:Standards_/_measurements]]		[[Category:Standards_/_measurements]]

195.195.140.13 at 15:39, 23 March 2017

2017-03-23T15:39:06Z

← Older revision		Revision as of 15:39, 23 March 2017
Line 1:		Line 1:
		+	I beat my meat to the sound of the beat

−	R-values are a measure of the thermal resistance of a material of a specific thickness, that is, its resistance to the transfer of heat across it. The higher the R-value of a material, the more effective it is as an insulator.	+	=== Related articles on Designing Buildings Wiki ===

−	R-values can be used as part of a labelling system to enable comparison of the thermal performance of different materials, such as insulation, or as part of the calculation of heat transfer across the fabric of a building.<br/>	+	* Aerogel insulation for buildings
−		+	* g-value.
−	R-values can be calculated by dividing the thickness of a material (in metres) by its thermal conductivity (k-value or lambda value (λ) in W/mK). R-values are therefore expressed in m2K/W (or ft2·°F·hr/Btu in the USA). The overall R-value of a multi-layered element can be calculated by adding the R-values of its component materials.<br/>	+	* k-value.
−		+	* Insulation.
−	R-values are sometimes described as being the reciprocal of U-values (sometimes referred to as heat transfer coefficients) which describe the thermal conductivity of a building element. However, unlike U-values, R-values do not include surface heat transfers at the boundary of the element by convection and radiation.	+	* Phase change materials.
−		+	* Shading coefficient.
−	~~U-value = 1 / (the sum of the R-values of the layers of the element + the resistance of the internal and external surfaces of the element)~~	+	* Solar heat gain coefficient.
−		+	* Thermal bridge.
−	~~= Find out more =~~	+	* Transparent insulation.
−		+	* U-value.
−	~~=== Related articles on Designing Buildings Wiki ===~~	+
−	*Aerogel insulation for buildings	+
−	*g-value.	+
−	*k-value.	+
−	*Insulation.	+
−	*Phase change materials.	+
−	*Shading coefficient.	+
−	*Solar heat gain coefficient.	+
−	*Thermal bridge.	+
−	*Transparent insulation.	+
−	*U-value.	+

	[[Category:Standards_/_measurements]]		[[Category:Standards_/_measurements]]

Designing Buildings at 15:38, 8 July 2014

2014-07-08T15:38:50Z

← Older revision		Revision as of 15:38, 8 July 2014
Line 24:		Line 24:
	*U-value.		*U-value.

−	[[Category:~~Sustainability~~]]	+	[[Category:Standards_/_measurements]]

Designing Buildings at 11:52, 29 January 2014

2014-01-29T11:52:02Z

← Older revision		Revision as of 11:52, 29 January 2014
Line 16:		Line 16:
	*g-value.		*g-value.
	*k-value.		*k-value.
−	*Insulation ~~specification~~.	+	*Insulation.
		+	*Phase change materials.
	*Shading coefficient.		*Shading coefficient.
	*Solar heat gain coefficient.		*Solar heat gain coefficient.
	*Thermal bridge.		*Thermal bridge.
		+	*Transparent insulation.
	*U-value.		*U-value.

	[[Category:Sustainability]]		[[Category:Sustainability]]

Designing Buildings at 13:16, 2 January 2014

2014-01-02T13:16:01Z

← Older revision		Revision as of 13:16, 2 January 2014
Line 14:		Line 14:
	=== Related articles on Designing Buildings Wiki ===		=== Related articles on Designing Buildings Wiki ===
	*Aerogel insulation for buildings		*Aerogel insulation for buildings
−	*U-value.
	*g-value.		*g-value.
		+	*k-value.
	*Insulation specification.		*Insulation specification.
	*Shading coefficient.		*Shading coefficient.
	*Solar heat gain coefficient.		*Solar heat gain coefficient.
	*Thermal bridge.		*Thermal bridge.
		+	*U-value.

	[[Category:Sustainability]]		[[Category:Sustainability]]

86.166.224.29 at 12:54, 2 January 2014

2014-01-02T12:54:17Z

← Older revision		Revision as of 12:54, 2 January 2014
Line 1:		Line 1:

−	R-values are a measure of the thermal resistance of a material, that is, its resistance to the transfer of heat across it. The higher the R-value of a material, the more effective it is as an insulator.	+	R-values are a measure of the thermal resistance of a material of a specific thickness, that is, its resistance to the transfer of heat across it. The higher the R-value of a material, the more effective it is as an insulator.

	R-values can be used as part of a labelling system to enable comparison of the thermal performance of different materials, such as insulation, or as part of the calculation of heat transfer across the fabric of a building.<br/>		R-values can be used as part of a labelling system to enable comparison of the thermal performance of different materials, such as insulation, or as part of the calculation of heat transfer across the fabric of a building.<br/>

Designing Buildings at 12:45, 19 December 2013

2013-12-19T12:45:03Z

← Older revision		Revision as of 12:45, 19 December 2013
Line 2:		Line 2:
	R-values are a measure of the thermal resistance of a material, that is, its resistance to the transfer of heat across it. The higher the R-value of a material, the more effective it is as an insulator.		R-values are a measure of the thermal resistance of a material, that is, its resistance to the transfer of heat across it. The higher the R-value of a material, the more effective it is as an insulator.

−	R-values can be used as part of a labelling system to enable comparison of the thermal performance of different materials, such as insulation, or as part of the calculation of heat transfer across ~~building~~ fabric.	+	R-values can be used as part of a labelling system to enable comparison of the thermal performance of different materials, such as insulation, or as part of the calculation of heat transfer across the fabric of a building.<br/>

−	R-values can be calculated by dividing the thickness of a material (in metres) by its thermal conductivity (k-value or lambda value (λ)) in W/mK. R-values are therefore expressed in m2K/W (or ft2·°F·hr/Btu in the USA) . The overall R-value of a multi-layered element can be calculated by adding the R-values of its component materials.	+	R-values can be calculated by dividing the thickness of a material (in metres) by its thermal conductivity (k-value or lambda value (λ) in W/mK). R-values are therefore expressed in m2K/W (or ft2·°F·hr/Btu in the USA). The overall R-value of a multi-layered element can be calculated by adding the R-values of its component materials.<br/>

	R-values are sometimes described as being the reciprocal of U-values (sometimes referred to as heat transfer coefficients) which describe the thermal conductivity of a building element. However, unlike U-values, R-values do not include surface heat transfers at the boundary of the element by convection and radiation.		R-values are sometimes described as being the reciprocal of U-values (sometimes referred to as heat transfer coefficients) which describe the thermal conductivity of a building element. However, unlike U-values, R-values do not include surface heat transfers at the boundary of the element by convection and radiation.